1998 Mercedes Benz SLK230 Workshop Manual

1998 Mercedes-benz SLK230 Submodel: | Engine Type: L4 | Liters: 2.3 Fuel Delivery: FI | Fuel: GAS

Before servicing any vehicle, please be sure to read all of the following precautions, which deal with personal safety, prevention of component damage and important points to take into consideration when servicing a motor vehicle:

Never open, service or drain the radiator or cooling system when the engine is hot; serious burns can occur from the steam and hot coolant. Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well-ventilated area. Do not allow fuel spray or vapors to come in contact with a spark, open flame or excessive heat (a hot drop light, for example). Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion. Refer to the additional fuel system precautions later in this section. Fuel injection systems often remain pressurized, even after the engine has been turned OFF OFF.. The fuel system pressure must be relieved before disconnecting any fuel lines. Failure to do so may result in fire and/or personal injury. Brake fluid often contains polyglycol ethers and polyglycols. Avoid contact with the eyes and wash your hands thoroughly after handling brake fluid. If you do get brake fluid in your eyes, flush your eyes with clean, running water for 15 minutes. If eye irritation persists, or if you have taken brake fluid internally, seek medical assistance IMMEDIATELY. The EPA warns that prolonged contact with used engine oil may cause a number of skin disorders, including cancer. You should make every effort to minimize your exposure to used engine oil. Protective gloves should be worn when changing oil. Wash your hands and any other exposed skin areas as soon as possible after exposure to used engine oil. Soap and water, or waterless hand cleaner should be used. All new vehicles are now now equipped with an an air bag sys tem. The system must be disabled before before performing performing service on or or around around system component components, s, s teer teering ing column, column, instrument instrument panel components, wiring and sensors. Failure to follow safety and disabling procedures could result in accidental air bag deployment, possible personal injury and unnecessary system repairs. Always wear safety safety goggles goggles when working working with, with, or arou around, nd, the air air bag sys tem. When carrying carrying a non-deployed non-deployed air air bag, be s ure the the bag and trim cover cover are pointed pointed away from from your your body. When placing a non-deployed air bag on a work surface, always face the bag and trim cover upward, away from the surface. This will reduce the motion of the module if it is accidentally deployed. Refer to the additional air bag system precautions later in this section. Clean, high quality brake fluid from a sealed container is essential to the safe and proper operation of the brake system. You should always buy the correct type of brake fluid for your vehicle. If the brake fluid becomes contaminated, completely flush the system with new fluid. Never reuse any brake fluid. Any brake fluid that is removed from the system should be discarded. Also, do not allow any brake fluid to come in contact with a painted surface; it will damage the paint. Never operate the engine without the proper amount and type of engine oil; doing so will result in severe engine damage. Timing belt maintenance is extremely important. Many models utilize an interference-type, non-freewheeling engine. If the timing belt breaks, the valves in the cylinder head may strike the pistons, causing potentially serious (also time-consuming and expensive) engine damage. Refer to the maintenance interval charts in the front of this manual for the recommended replacement interval for the timing belt and to the timing belt section for belt replacement and inspection. Disconnecting the negative battery cable on some vehicles may interfere with the functions of the on-board computer system(s) and may require the computer to undergo a relearning process once the negative battery cable is reconnected. When servicing drum brakes, only disassemble and assemble one side at a time, leaving the remaining side intact for reference. Only an MVAC-trained, EPA-certified automotive technician should service the air conditioning system or its components.


A basic vehicle c oo ooling ling system consists of a radiator radiator, water pump, ther thermost mostat, at, electric electric or engine-driven engine-driven cooling cooling fan, and hoses. hoses. Electric Electric cooling cooling fans fans are common common on tod today's ay's vehicles due to engine compartment space limitations or engine layout. Electric cooling fans operate in either a pusher or a puller capacity. A pusher type fan is typically mounted on the front of the radiator assembly and forces air through the radiator, whereas a puller type fan is mounted on the engine side of the radiator and draws air through the grill and radiator assembly. Vehicles that utilize a transversely-mounted engine will always be equipped with at least one electric cooling fan (most having two), because none of the engine pulleys are inline with the radiator air-flow. Typical dual fan set-up, showing common cooling fan system control components used on many vehicles with A/C

There are generally two types of electric cooling fans: primary cooling fans and secondary cooling fans. Primary cooling fans are typically of the puller style. Vehicles that do not incorporate an engine-driven mechanical cooling fan will utilize a primary cooling fan. The secondary cooling fan, also known as a A/C condenser fan or auxiliary cooling fan by certain manufacturers, could be of either a pusher or a puller style. Vehicles equipped with A/C will either utilize the radiator cooling fan or a separate fan as the A/C condenser cooling fan (which performs the same function as an auxiliary cooling fan on vehicles with a primary mechanical fan). The engine control computer that receives inputs from various sensors in the engine compartment commonly controls electric cooling fans. The engine control computer receives inputs from the engine coolant temperature sensors and A/C system pressure switches, then actuates the necessary cooling fan relays to engage the applicable cooling fan for the condition. On models equipped with only one electric primary cooling fan, the fan can operate at two speeds: low speed and high speed. The low speed condition is enabled when the engine begins to heat up or when the A/C is engaged. As the engine demands more cooling, the cooling fan will be stepped-up to high speed.


A basic vehicle c oo ooling ling system consists of a radiator radiator, water pump, ther thermost mostat, at, electric electric or engine-driven engine-driven cooling cooling fan, and hoses. hoses. Electric Electric cooling cooling fans fans are common common on tod today's ay's vehicles due to engine compartment space limitations or engine layout. Electric cooling fans operate in either a pusher or a puller capacity. A pusher type fan is typically mounted on the front of the radiator assembly and forces air through the radiator, whereas a puller type fan is mounted on the engine side of the radiator and draws air through the grill and radiator assembly. Vehicles that utilize a transversely-mounted engine will always be equipped with at least one electric cooling fan (most having two), because none of the engine pulleys are inline with the radiator air-flow. Typical dual fan set-up, showing common cooling fan system control components used on many vehicles with A/C

There are generally two types of electric cooling fans: primary cooling fans and secondary cooling fans. Primary cooling fans are typically of the puller style. Vehicles that do not incorporate an engine-driven mechanical cooling fan will utilize a primary cooling fan. The secondary cooling fan, also known as a A/C condenser fan or auxiliary cooling fan by certain manufacturers, could be of either a pusher or a puller style. Vehicles equipped with A/C will either utilize the radiator cooling fan or a separate fan as the A/C condenser cooling fan (which performs the same function as an auxiliary cooling fan on vehicles with a primary mechanical fan). The engine control computer that receives inputs from various sensors in the engine compartment commonly controls electric cooling fans. The engine control computer receives inputs from the engine coolant temperature sensors and A/C system pressure switches, then actuates the necessary cooling fan relays to engage the applicable cooling fan for the condition. On models equipped with only one electric primary cooling fan, the fan can operate at two speeds: low speed and high speed. The low speed condition is enabled when the engine begins to heat up or when the A/C is engaged. As the engine demands more cooling, the cooling fan will be stepped-up to high speed.


Puller Type NOTE: It may be simpler to remove the cooling fan(s) with the radiator as an assembly.

1.

Dis connect the negative battery cab le.

2.

Inspec t the cooling fan fan and take note note of of any wires, hoses or A/C lines which may hamp er fan removal. removal. Also at this time, decide whether it is neces sary to remove remove the fan along along with the radiator or not.

3.

Position aside all wires, hoses and A/C lines for fan removal. removal. It may not always b e possib le to create enough clearanc e for for fan removal by si mply moving these obs obs tructions aside; often they must be disconnected. If any cooling system lines must be disconnected, drain and recycle the engine coolant. If any of the A/C lines must be disconnected, the A/C sys tem will need need to be disc harge harged d and evacuated evacuated by a MVAC-trained MVAC-trained technician technician using an approved recovery recovery machine. Exploded view of a typical dual cooling fan set-up and related cooling system components

4.

Dis engage the cooling fan wiring harness connector. connector.

5.

If the fan can be removed without the radia radiator tor,, perform the following: A. B.

6.

Loosen the Loosen the mountin mounting g fasteners. fasteners. Usually there there are two two nuts nuts or or bolts bolts along the the top top edge of the cooling cooling fan shroud shroud and either either two two retain retaining ing clips or bolts bolts along along the bottom edge. Carefully lift the fan fan up and out of the engine compartment, making sure that no wires or hoses hoses get hung up on it.

If it is necess ary to remove the radiator fo forr fan removal, perform the fo following: llowing: A. B.

Disc on onnect nect all cooling system hoses from it after after draining draining the cooling cooling sys tem. Locate all of of the radiator mounting fasteners fasteners (usual ly two or or more nuts or bolts bolts along the top, possi bly two along the the bottom). NOTE: Quite a few radiators are secured along the bottom by two posts which fit into rubber grommets. The rubber grommets help isolate the radiator from harsh vibrations in the frame. If no nuts or bolts can be located along the bottom of the radiator, chances are that the radiator is s ecured with the posts posts and gr ommet ommets. s.

C.

Lift the the radiator and cooling fan up and out of the engine compartment compartm ent together. together.

D.

Separate the cooling fan fro from m the radiator by removing the attaching fasteners. fasteners. To remove a puller type cooling fan, first detach any braces (1), wires (2) or other obstructions...

... including cooling system hoses, to allow fan removal

Disengage the fan wiring connector(s)...

... and loosen al l fan m ounting fasteners

Separate the fan from the radiator...

..., then lift the fan up and out of the engine compartment

To install:

7.

If app licab le, install the cooling fan on the radiator.

8.

Install the cooling fan and shroud assemb ly (also the radiator if necessary ). Tighten the fan shroud mounting bolts.

9.

Reattach all wires, hoses and A/C lines as appl icab le. If the A/C lines were detached, the sy stem must be evac uated and recharged by a MVAC-trained technici an.

10.

If drained, refill and bleed the cooling sy stem.

11.

Reattach the cooling fan electric al harness connector.

12.

Connect the negative battery cab le.

13.

Start the engine and check for leaks .

14.

Verify the operation of the cooling fan(s). Typical mounting of a puller type cooling fan assembly utilizing retaining clips and screws — note that this particular model uses a dual puller fan setup

Notice the slots i n the b ottom of the radiator, i n whic h the fan housing posts rest — common mounting of a puller type cooling fan.

This fan m ounts to the fan s hroud, then the shroud mounts to the radiator — molded clips in the radiator hold the bottom in place and screws at the top.

Typically the cooling fan is rubber mounted to isolate vibration and noise — usually the rubber grommets are located at the mount, verify their position before installation

Pusher Type Vehicles that utilize the pusher type of electric cooling fan, may require the removal of the grilles and/or upper radiator shroud in order to gain access the fasteners that mount the fan assembly in the vehicle.

1.


2.

Acc ess the cooling fan.

3.

Label and disc onnect the cooling fan electric al harness.

4.

Remove the fasteners that mount the cooling fan to the A/C condens er or radiator.

5.

Lift the cooling fan out of the vehi cl e.

NOTE: It may be necessary to loosen the mounting bolts for the A/C condenser to the body

After removal of the grill assembly, the pusher type of cooling fan can be removed

It may be necess ary to remove the grill ass embly to access the A/C condenser cooling fan — pusher type

To install: 6.

Insert the cooling fan into the vehic le.

7.

Mount the cooling fan to the A/C condenser or radiator

8.

Connect the cooling fan electric al harness .

9.

If removed, install any shrouding or grills .

10.



When diagnosing an inoperative cooling fan it may b e necessary to use a diagnostic scan tool to monitor engine coolant temperature and the engine control computer.

1.

Perform a vis ual insp ection of the cooling fan. If the fan does not turn with ease, the fan motor is sei zed and needs to be rep laced.

2.

Check all the fuses and fusib le links related to the cooling fan circ uit.

3.

Check the integrity of the electric al connections related to the cooling fan circ uit.

4.

Check the cooling fan motor.

5.

Check the relays associ ated with the cooling fan circ uit.

6.

Using a scan tool, determine if the engine control computer is cal ling for the fan to activate.

Cooling Fan Motor

1.


2.

Disengage the cooling fan motor connec tor.

3.

Identify and label the ground and the power terminals of the cooling fan connector using the wiring diagrams p rovided.

4.

Using jumper leads with a fuse in series, app ly battery voltage to the app ropriate terminals of the cooling fan.

5.

The cooling fan should operate. If not, replac e the cooling fan. If the cooling fan functions properly during this test, proceed to the cooling fan relay test.

Cooling Fan Relay

1.

Turn the ignition OFF.

2.

Remove the relay.

3.

Locate the two terminals on the relay, which are connected to the coil windings. Check the relay coil for continuity. Connect the common meter lead to terminal 85 and positiv e meter lead to terminal 86. There should be continuity. If not, replace the relay. Use an ohmmeter to check for circuit continuity of the coil in the relay

4.

Check the operation of the internal relay contacts. A. B.

Connect the meter leads to terminals 30 and 87. Meter polarity does not matter for this step. App ly positiv e battery voltage to terminal 86 and ground to terminal 85. The relay should clic k as the contacts are drawn toward the coil and the meter should indicate continuity. Replace the relay if your results are different. If the relay functions properly during this test, inspect the coolant temperature sensor and the cooling fan system wiring for defects. Terminal identification of the most common types of relays. Diodes and resistors in the relay prevent voltage spikes induced when the current is removed from the coil from damaging electronic components

DIA. 42 - 1997 –01 Mercedes-Benz C220 / C280 2.2L / 2.8L

DIA. 43 - 199 7–01 Mercedes-Benz E320 / E420 3 .2L / 4.2L

DIA. 44 - 1997–01 Mercedes-Benz S320 / S420 / S501 3.2L / 4.2L / 5.0L


An oxygen (O2S) sensor is an input device used by the engine control computer to monitor the amount of oxygen in the exhaust gas stream. The information is used by the computer, along with other inputs, to fine-tune the air/fuel mixture so that the engine can run with the greatest efficiency in all conditions. The O2S sensor sends this information to the computer in the form of a 100–900 millivolt (mV) reference signal. The signal is actually created by the O2S sensor itself through chemical interactions between the sensor tip material (zirconium dioxide in almost all cases) and the oxygen levels in the exhaust gas stream and ambient atmosphere gas. At operating temperatures, approximately 1100°F (600°C), the element becomes a semiconductor. Essentially, through the differing levels of oxygen in the exhaust gas stream and in the surrounding atmosphere, the sensor creates a voltage signal that is directly and consistently related to the concentration of oxygen in the exhaust stream. Typically, a higher than normal amount of oxygen in the exhaust stream indicates that not all of the available oxygen was used in the combustion process, because there was not enough fuel (lean condition) present. Inversely, a lower than normal concentration of oxygen in the exhaust stream indicates that a large amount was used in the combustion process, because a larger than necessary amount of fuel was present (rich condition). Thus, the engine control computer can correct the amount of fuel introduced into the combustion chambers. Since the control computer uses the O2S sensor output voltage as an indication of the oxygen concentration, and the oxygen concentration directly affects O2S sensor output, the signal voltage from the sensor to the computer fluctuates constantly. This fluctuation is caused by the nature of the interaction between the computer and the O2S sensor, which follows a general pattern: detect, compare, compensate, detect, compare, compensate, etc. This means that when the computer detects a lean signal from the O2S sensor, it compares the reading with known parameters stored within its memory. It calculates that there is too much oxygen present in the exhaust gases, so it compensates by adding more fuel to the air/fuel mixture. This, in turn, causes the O2S sensor to send a rich signal to the computer, which, then compares this new signal, and adjusts the air/fuel mixture again. This pattern constantly repeats itself: detect rich, compare, compensate lean, detect lean, compare, compensate rich, etc. Since the O2S sensor fluctuates between rich and lean, and because the lean limit for sensor output is 100 mV and the rich limit is 90 0 mV, the p roper voltage signal from a normally functioning O2S s ensor consistently fluctuates between 100–300 and 700 –900 mV. NOTE: The sensor voltage may never quite reach 100 or 900 mV, but it should fluctuate from at least below 300 mV to above 700 mV, and the mid-point of the fluctuations should be centered around 500 mV. To improve O2S sensor efficiency, newer O2S sensors were designed with a built-in heating element, and were called Heated O2S (HO2S) sensors. This heating element was incorporated into the sensor so that the sensor would reach optimal operating temperature quicker, meaning that the O2S sensor output signal could be used by the engine control computer sooner. Because the sensor reaches optimal temperature quicker, modern vehicles enjoy improved driveability and fuel economy even before the engine reaches normal operating temperature. On-Board Diagnostics second generation (OBD-II), an updated system based on the former OBD-I, calls for additional O2S sensors to be used after the catalytic converter, so that catalytic converter efficiency can be measured by the vehicle's engine control computer. The O2S sensors mounted in the exhaust system after the catalytic converters are not used to affect air/fuel mixture; they are used solely to monitor catalytic converter efficiency. A cut away view of a Heated Oxygen (HO2S) sensor

O2S sensor output voltage vs. mixture ratio


When testing or servicing an Oxygen (O2S) sensor you will need to start and warm the engine to operating temperature in order to either perform the necessary testing procedures or to easily remove the sensor from its fitting. This will create a situation in which you will be working around a HOT exhaust system. The following is a list of precautions to consider during this service:

Do not pierce any wires when testing an O2S sensor, as this can lead to wiring harness damage. Backprobe the connector, when necessary. While testing the sensor, be sure to keep out of the way of moving engine components, such as the cooling fan. Refrain from wearing loose clothing that may become tangled in moving engine components. Safety glasses must be worn at all times when working on or near the exhaust system. Older exhaust systems may be covered with loose rust particles that can shower you when disturbed. These particles are more than a nuisance and can injure your eye. Be cautious when working on and around the hot exhaust system. Painful burns will result if skin is exposed to the exhaust system pipes or manifolds. The O2S sensor may be difficult to remove when the engine temperature is below 120°F (48°C). Excessive force may damage the threads in the exhaust manifold or pipe, therefore always start the engine and allow it to reach normal operating temperature prior to removal. Since O2S sensors are usually designed with a permanently attached wiring pigtail (this allows the wiring harness and sensor connectors to be positioned away from the hot exhaust sys tem), it may be necessary to use a s ocket or wrench that is designed specifically for this p urpose. Before purchasing s uch a s ocket, be sure that you can't save s ome money by using a box end wrench for sensor removal.


The best, and most accurate method to test the operation of an Oxygen (O2S) sensor is with the use of either an oscilloscope or a Diagnostic Scan Tool (DST), following their specific instructions for testing. It is possible, however, to test whether the O2S sensor is functioning properly within general parameters using a Digital Volt-Ohmmeter (DVOM), also referred to as a Digital Multi-Meter (DMM). Newer DMM's are often designed to perform many advanced diagnostic functions. Some are constructed to be used as an oscilloscope. Two in-vehicle testing procedures, and 1 bench test procedure, will be provided for the common zirconium dioxide O2S sensor. The first in-vehicle test makes use of a standard DVOM with a 10 megohms impedance, whereas the second in-vehicle test presented necessitates the usage of an advanced DMM with MIN/MAX/Average functions. Both of these in-vehicle test procedures are likely to set Diagnostic Trouble Codes (DTC's) in the engine control computer. Therefore, after testing, be sure to clear all DTC's before retesting the sensor, if necessary. These are some of the common DTC's which may be set during testing:

Open in the O2S sensor circuit Constant low voltage in the O2S sensor circuit Constant high voltage in the O2S sensor circuit Other fuel system problems c ould set a O 2S sensor code NOTE: Because an improperly functioning fuel delivery and/or control system can adversely affect the O2S sensor voltage output signal, testing only the O2S sensor is an inaccur ate method for diagnosing an engine driveability problem. If after testing the sensor, the sensor is thought to be defective because of high or low readings, be sure to check that the fuel delivery and engine management system is working properly before condemning the O2S sensor. Otherwise, the new O2S sensor may continue to register the same high or low readings. Often, by testing the O2S sensor, another problem in the engine control management system can be diagnosed. If the sensor appears to be defective while installed in the vehicle, perform the bench test. If the sensor functions properly during the bench test, chances are that there may be a larger problem in the vehicle's fuel delivery and/or control system. Many things can cause an O2S sensor to fail, including old age, antifreeze contamination, physical damage, prolonged exposure to overly-rich exhaust gases, and exposure to silicone sealant fumes. Be sure to remedy any such condition prior to installing a new sensor, otherwise the new sensor may be damaged as well. NOTE: Perform a visual inspection of the sensor. Black sooty deposits may indicate a rich air/fuel mixture, brown deposits may indicate an oil consumption problem, and white gritty deposits may indicate an internal coolant leak. All of these conditions can destroy a new sensor if not corrected before installation.

Oxygen (O2S) Sensor Terminal Identification The easiest method for determining sensor terminal identification is to use a wiring diagram for the vehicle and engine in question. However, if a wiring diagram is not available there is a method for determining terminal identification. Throughout the testing procedures, the following terms will be used for clarity:

Vehicle harness connector — this refers to the connector on the wires which are attached to the vehicle, NOT the connector at the end of the sensor pigtail Sensor pigtail connector — this refers to the connector attached to the sensor itself Oxygen (O2S) sensor circuit — this refers to the circuit in a Heated Oxygen (HO2S) sensor which corresponds to the oxygen-sensing function of the sensor; NOT the heating element circuit Heating circuit — this refers to the circuit in a HO2S sensor which is designed to warm the HO2S sensor quickly to improve driveability Sensor Output ( SOUT) terminal — this is the terminal which corresponds to the O2S circuit output. This is the terminal that will register the millivolt signals created by the sensor based upon the amount of oxygen in the exhaust gas stream. Sensor Ground ( SGND) terminal — when a sensor is so equipped, this refers to the O2S circuit ground terminal. Many O2S sensors are not equipped with a ground wire, rather they utilize the exhaust system for the ground circuit. Heating Power ( HPWR) terminal — this terminal corresponds to the circuit which provides the O2S sensor heating circuit with power when the ignition key is turned to the ON or RUN positions Heating Ground ( HGND) terminal — this is the terminal connected to the heating circuit ground wire Wiring schematic of typical 1-, 2-, 3- and 4-wire oxygen sensor circuits

1-WIRE SENSOR

1-wire sensors are by far the easiest to determine sensor terminal identification, but this is self-evident. On 1-wire O2S sensors, the single wire terminal is the SOUT and the exhaust system is used to provide the sensor ground pathway. Proceed to the test procedures.

2-WIRE SENSOR

On 2-wire sensors, one of the connector terminals is the SOUT and the other is the SGND. To determine which one is which, perform the following:

1.

Locate the Oxygen (O2S ) sensor and its pigtail connector. It may be necessary to raise and safely sup port the vehicle to gain acces s to the connector.

2.

Start the engine and allow it to warm up to normal operating temperature, then turn the engine OFF.

3.

Using a Digital Volt Ohm Meter (DVO M) set to read 100–9 00 mV (mill ivolts) DC, bac kp robe the positive DVO M lead to one of the unidentified terminals and attach the negative lead to a good engine ground.

CAUTION While the engine is running, keep clear of all moving and hot components. Do not wear loose clothing. Otherwise severe personal injury or death may occur. 4.

Have an ass istant restart the engine and allow it to idle.

5.

Check the DVO M for voltage.

6.

If no voltage is evident, chec k your DVO M leads to ensure that they are properly c onnected to the terminal and engine ground. If still no voltage is evident at the first terminal, move the positive meter lead to backprobe the second terminal.

7.

If voltage is now pres ent, the positive meter lead is attached to the SOUT terminal. The remaining terminal is the SGND terminal. If still no voltage is evident, either the O2S sensor is defective or the meter leads are not making adequate contact with the engine ground and terminal contacts; clean the contacts and retest. If still no voltage is evident, the sensor is defective.

8.

Have your ass istant turn the engine OFF.

9.

Label the sensor pigtail SOUT and SGND terminals.

10.

Proceed to the test procedures.

3-WIRE SENSOR

NOTE: 3-wire sensors are HO2S sensors. On 3-wire sensors, one of the connector terminals is the SOUT, one of the terminals is the HPWR and the other is the HGND. The SGND is achieved through the exhaust system, as with the 1-wire O2S sensor. To identify the 3 terminals, perform the following:

1.

Locate the O2S sensor and its pigtail connector. It may be necess ary to raise and safely sup port the vehicle to gain acc ess to the connector.

2.

Dis engage the sens or pigtail connector from the vehic le harness connector.

3.

Using a Digital Volt Ohm Meter (DVOM) set to read 12 volts, attach the DVOM ground lead to a good engine ground.

4.

Have an ass istant turn the ignition switch ON without actually starting the engine.

5.

Probe all 3 terminals in the vehicle harness c onnector. One of the terminals s hould exhibit 12 volts of power with the ignition key ON; this is the HPWR terminal. A. B.

If the HPWR terminal was identified, note which of the sensor harness connector terminals is the HPWR, then match the vehicle harness connector to the sensor pigtail connector. Label the corresponding sensor pigtail connector terminal with HPWR. If none of the terminals showed 12 volts of power, locate and test the heater relay or fuse. Then, perform Steps 3 –6 again.

6.


7.

Have your ass istant turn the ignition OFF.

8.

Using the DVO M set to measure resis tance (ohms), attach one of the leads to the HPWR terminal of the sensor pigtail connector. Use the other lead to probe the 2 remaining terminals of the sensor pigtail connector, one at a time. The DVOM should show continuity with only one of the remaining unidentified terminals; this is the HGND terminal. The remaining terminal is the SOUT. A. B.

9.

If continuity was found with only one of the 2 unidentified terminals, label the HGND and SOUT terminals on the sensor pigtail connector. If no continuity was evident, or if continuity was evident from both unidentified terminals, the O2S sens or is defective.

All 3-wire terminals should now be labeled on the sensor pigtail connector. Proceed with the test procedures.

4-WIRE SENSOR

NOTE: 4-wire sensors are HO2S sensors. On 4-wire sensors, one of the connector terminals is the SOUT, one of the terminals is the SGND, one of the terminals is the HPWR and the other is the HGND. To identify the 4 terminals, perform the following:

1.

Locate the O2S sensor and its pigtail connector. It may be necess ary to raise and safely sup port the vehicle to gain acc ess to the connector.

2.


3.

Using a Digital Volt Ohm Meter (DVOM) set to read 12 volts, attach the DVOM ground lead to a good engine ground.

4.

Have an ass istant turn the ignition switch ON without actually starting the engine.

5.

Probe all 4 terminals in the vehicl e harness connector. One of the terminals should exhibi t 12 volts of power with the ignition key ON; this is the HPWR terminal. A. B.

If the HPWR terminal was identified, note which of the sensor harness connector terminals is the HPWR, then match the vehicle harness connector to the sensor pigtail connector. Label the corresponding sensor pigtail connector terminal with HPWR. If none of the terminals showed 12 volts of power, locate and test the heater relay or fuse. Then, perform Steps 2–6 again.

6.

Have your ass istant turn the ignition OFF.

7.

Using the DVO M set to measure resis tance (ohms), attach one of the leads to the HPWR terminal of the sensor pigtail connector. Use the other lead to probe the 3 remaining terminals of the sensor pigtail connector, one at a time. The DVOM should show continuity with only one of the remaining unidentified terminals; this is the HGND terminal. A.

If continuity was found with only 1 of the 2 unidentified terminals, label the HGND terminal on the sensor pigtail connector.

B.

If no continuity was evident, or if continuity was evident from all unidentified terminals , the O2S sens or is defective.

C.

If continuity was found at 2 of the other terminals, the sensor is probably defec tive. However, the sens or may not neces sarily b e defective, becaus e it may have been designed with the 2 ground wires joined inside the sensor in case one of the ground wires is damaged; the other circuit could still function properly. Though, this is highly unlikely. A wiring diagram is necessary in this particular case to know whether the sensor was so designed.

8.

Reattach the sens or pigtail connector to the vehic le harness connector.

9.


10.

Using a DVOM set to read 100–9 00 mV (mil livolts) DC, bac kp robe the negative DVO M lead to one of the unidentified terminals and the positiv e lead to the other unidentified terminal. CAUTION While the engine is running, keep clear of all moving and hot components. Do not wear loose clothing. Otherwise severe personal injury or death may occur.

11.

Have an ass istant restart the engine and allow it to idle.

12.

Check the DVO M for voltage. A.

If no voltage is evident, check your DVOM leads to ensure that they are properly connected to the terminals. If still no voltage is evident at either of the terminals, either the terminals were accidentally marked incorrectly or the sensor is defective.

B.

If voltage is present, but the polarity is revers ed (the DVO M will show a negative voltage amount), turn the engine OFF and swap the 2 DVOM leads on the terminals. Start the engine and ensure that the voltage now shows the proper polarity.

C.

If voltage is evident and is the proper polarity, the positive DVOM lead is attached to the SOUT and the negative lead to the SGND terminals.

13.

Have your ass istant turn the engine OFF.

14.

Label the sensor pigtail SOUT and SGND terminals.

In-Vehicle Tests WARNING Never apply voltage to the O2S circuit of the sensor, otherwise it may be damaged. Also, never connect an ohmmeter (or a DVOM set on the ohm function) to both of the O2S circuit terminals (

SOUT and SGND) of the sensor pigtail connector; it may damage the sensor. Test 1 makes use of a standard DVOM with a 10 megohms impedance, whereas Test 2 necessitates the usage of an advanced Digital Multi-Meter (DMM) with MIN/MAX/Average functions or a sliding bar graph function. Both of these in-vehicle test procedures are likely to set Diagnostic Trouble Codes (DTC's) in the engine control computer. Therefore, after testing, be sure to clear all DTC's before retesting the sensor, if necessary. The third in-vehicle test is designed for the use of a scan tool or oscilloscope. The 4th test (Heating Circuit Test) is designed to check the function of the heating circuit in a HO2S sensor. NOTE: If the O2S sensor b eing tested is d esig ned to use the exhaust system for the SGND, exces sive corr osion between the exhaust and the O2S sensor may affect sensor functioning. The in-vehicle tests may be performed for O2S sensors located in the exhaust system after the catalytic converter. However, the O2S sensors located behind the catalytic converter will not fluctuate like the sensors mounted before the converter, because the converter, when functioning properly, emits a steady amount of oxygen. If the O2S sensor mounted after the catalytic converter exhibits a fluctuating signal (like other O2S sensors), the catalytic converter is most likely defective. To test the O2S sensor, locate it and its connector (inset), which should be positioned away from the exhaust system to prevent heat damage.

TEST 1 — DIGITAL VOLT-OHMMETER

This test will not only verify proper sensor functioning, but is also designed to ensure the engine control computer and associated wiring is functioning properly as well.

1.

Start the engine and allow it to warm up to normal operating temperature. NOTE: If you are using the opening of the thermostat to gauge normal operating temperature, be forewarned: a defective thermostat can open too early and prevent the engine from reaching normal operating temperature. This can cause a slightly rich condition in the exhaust, which can throw the O2S sensor r eadings off slightly.

2.

Turn the ignition switch OFF, then locate the O2S sensor pigtail connector.

3.

Perform a vis ual insp ection of the connector to ensure it is properl y engaged and all terminals are straight, tight and free from corrosion or damage.

4.


5.

On sensors equipped with a SGND terminal (sensors which do not use the exhaust system for the sensor ground pathway), connect a jumper wire to the SGND terminal and to a good, clean engine ground (preferably the negative terminal of the battery).

6.

Using a Digital Volt Ohm Meter (DVO M) set to read DC voltage, attach the positive lead to the SOUT terminal of the sensor pigtail connector, and the DVOM negative lead to a good engine ground. CAUTION While the engine is running, keep clear of all moving and hot components. Do not wear loose clothing. Otherwise severe personal injury or death may occur.

7.

Have an assis tant start the engine and hold it at app roximately 200 0 rpm. Wait at least 1 minute before commencing with the test to allow the O2S sens or to sufficiently warm up.

8.

Using a jump er wire, connect the SOUT terminal of the vehicle harness connector to a good engine ground. This will fool the engine c ontrol computer i nto thinking it i s receiving a lean signal from the O2S sensor,, therefore, the computer will richen the air/fuel ratio. With the SOUT terminal so grounded, the DVOM should register at least 800 mV, as the control computer adds additional fuel to the air/fuel ratio.

9.

While observi ng the DVO M, disc onnect the vehic le harness connector SOUT jumper wire from the engine ground. Use the jumper wire to apply slightly less than 1 volt to the SOUT terminal of the vehicle harness connector. One method to do this is by grasping and squeezing the end of the jumper between your forefinger and thumb of one hand while touching the positive terminal of the battery post with your other hand. This allows your body to act as a resistor for the battery positive voltage, and fools the engine control computer into thinking it is receiving a rich signal. Or, use a mostly-drained AA battery by connecting the positive terminal of the AA battery to the jumper wire and the negative terminal of the battery to a good engine ground. (Another jumper wire may be necessary to do this.) The computer should lean the air/fuel mixture out. This lean mixture should register as 150 mV or less on the DVO M.

10.

If the DVO M did not register milli voltages as indic ated, the problem may b e either the sensor, the engine control computer or the associated wiring. Perform the following to determine which is the defective component: A. B.

Remove the vehicle harness c onnector SOUT jumper wire. While obs erving the DVO M, artificially enric h the air/fuel charge using propane. The DVOM reading should register higher than normal milliv oltages. (Normal voltage for an ideal air/fuel mixture is approximately 450–550 mV DC). Then, lean the air/fuel intake charger by either disconnecting one of the fuel injector wiring harness connectors (to prevent the injector from delivering fuel) or by detaching 1 or 2 vacuum lines (to add additional non-metered air into the engine). The DVOM should now register lower than normal millivoltages. If the DVOM functioned as indicated, the problem lies elsewhere in the fuel delivery and control system. If the DVOM readings were still unresponsive, the O2S sensor is defective; replace the sensor and retest. NOTE: Poor wire connections and/or gr ound circ uits may shift a normal O2S sensor's millivoltage readings up into the rich range or down into the lean range. It is a good idea to check the wire condition and continuity before replacing a component that will not fix the problem. A voltage dr op test between the sensor c ase and gr ound which reveals 14–16 mV or more, indicates a prob able bad ground.

11.

Turn the engine OFF, remove the DVOM and all associated jumper wires. Reattach the vehicle harness connector to the sensor pigtail connector. If applicable, reattach the fuel injector wiring connector and/or the vacuum line(s).

12.

Clear any DTC's present in the engine control computer memory, as necess ary.

TEST 2 — DIGITAL MULTI-METER

This test method is a more straight-forward O2S sensor test, and does not test the engine control computer's response to the O2S sensor signal. The use of a DMM with the MIN/MAX/Average function or sliding bar graph/wave function is necessary for this test. Don't forget that the O2S sensor mounted after the catalytic converter (if equipped) will not fluctuate like the other O2S sensor(s) will.

1.

Start the engine and allow it to warm up to normal operating temperature. NOTE: If you are using the opening of the thermostat to gauge normal operating temperature, be forewarned: a defective thermostat can open too early and prevent the engine from reaching normal operating temperature. This can cause a slightly rich condition in the exhaust, which can throw the O2S s ens or r ead in s o ff sl i h tl .

2.

Turn the ignition switch OFF, then locate the O2S sensor pigtail connector.

3.


4.

Back probe the O2S sens or connector terminals. Attach the DMM positive test lead to the SOUT terminal of the sensor pigtail connector. Attach the negative lead to either the SGND terminal of the sensor pigtail connector (if equipped, refer to the terminal identification procedures earlier in this section for clarification) or to a good, clean engine ground.

5.

Activ ate the MIN/MAX/A verage or slidi ng bar graph/wave function on the DMM. CAUTION While the engine is running, keep clear of all moving and hot components. Do not wear loose clothing. Otherwise severe personal injury or death may occur.

6.

Have an assis tant start the engine and wait a few minutes before commencing with the test to allow the O2S sens or to sufficiently warm up .

7.

Read the minimum, maximum and average readings exhib ited by the O2S sens or or observ e the bar graph/ wave form. The average reading for a properly functioning O2S sensor is b e app roximately 450–550 mV DC. The minimum and maximum readings should vary more than 300–600 mV. A typical O 2S sensor can fluctuate from as low as 100 mV to as high as 900 mV; if the sensor range of fluctuation is not large enough, the sensor is defective. Also, if the fluctuation range is biased up or down in the scale. For example, if the fluctuation range is 400 mV to 900 mV the sensor is defective, because the readings are pushed up into the rich range (as long as the fuel delivery system is functioning properly). The same goes for a fluctuation range pushed down into the lean range. The mid-point of the fluctuation range should be around 400–500 mV. Finally, if the O2S sensor voltage fluctuates too slowly (usually the voltage wave should oscillate past the mid-way point of 500 mV several times per second) the sensor is defective. (When an O2S sensor fluctuates too slowly, it is referred to as being "lazy.") NOTE: Poor wire connections and/or gr ound circ uits may shift a normal O2S sensor's millivoltage readings up into the rich range or down into the lean range. It is a good idea to check the wire condition and continuity before replacing a component that will not fix the problem. A voltage drop test between the sensor c ase and ground which r eveals 14–16 mV or more, indicates a probable b ad gr ound.

8.

Using the propane method, richen the air/fuel mixture and obs erve the DMM readings. The average O2S sens or output signal voltage should rise into the rich range.

9.

Lean the air/fuel mixture by either disc onnecting a fuel injector wiring harness connector or by dis connecting a vac uum line. The O2S sens or average output signal voltage should drop into the lean range.

10.

If the O2S sens or did not react as indicated, the sensor is defective and should be replaced.

11.

Turn the engine OFF, remove the DMM and all associated jumper wires. Reattach the vehicle harness connector to the sensor pigtail connector. If applicable, reattach the fuel injector wiring connector and/or the vacuum line(s).

12.


TEST 3 — OSCILLOSCOPE

This test is designed for the use of an oscilloscope to test the functioning of an O2S sensor. NOTE: This test is only applicable for O2S sensors mounted in the exhaust system before the catalytic converter.

1.

Start the engine and allow it to reach normal operating temperature.

2.

Turn the engine OFF, and locate the O2S sensor connector. Backprobe the scope lead to the O2S sensor connector SOUT terminal. Refer to the manufacturer's instructions for more information on attaching the scope to the vehicle.

3.

Turn the sc ope ON.

4.

Set the oscillosc ope amplitude to 200 m V per divis ion, and the time to 1 second per divis ion. Use the 1:1 setting of the probe, and be sure to connect the sc ope's ground lead to a good, clean engine ground. Set the signal function to automatic or internal triggering.

5.

Start the engine and run it at 200 0 rpm.

6.

The oscilloscope should display a wave form, representative of the O2S sensor switching between lean (100–3 00 mV) and rich (700–9 00 mV). The sensor should switch between rich and lean, or lean and rich (crossing the mid-point of 500 mV) several times per second. Also, the range of each wave should reach at least above 700 mV and below 300 mV. However, an occasional low peak is acceptable.

7.

Force the air/fuel mixture rich by introducing propane into the engine, then obs erve the osc illoscope readings . The fluctuating range of the O2S sens or should climb into the rich range.

8.

Lean the air/fuel mixture out by either detaching a vacuum line or by disengaging one of the fuel injector's wiring c onnectors. Watch the sc ope readings; the O2S sens or wave form s hould drop toward the lean range.

9.

If the O2S sens or's wave form does not fluctuate adequately, is not centered around 500 mV during normal engine operation, does not climb toward the rich range when propane is added to the engine, or does not drop toward the lean range when a vacuum hose or fuel injector connector is detached, the sensor is defective.

10.

Reattach the fuel injector connector or vac uum hose.

11.

Dis connect the oscill oscope from the vehic le. An oscilloscope wave form of a typical good O2S sensor as it fluctuates from rich to lean

HEATING CIRCUIT TEST

The heating circuit in an O2S sensor is designed only to heat the sensor quicker than a non-heated sensor. This provides an advantage of increased engine driveability and fuel economy while the engine temperature is still below normal operating temperature, because the fuel management system can enter closed loop operation (more efficient than open loop operation) sooner. Therefore, if the heating element goes bad, the O2S sensor may still function properly once the sensor warms up to its normal temperature. This will take longer than normal and may cause mild driveability-related problems while the engine has not reached normal operating temperature. If the heating element is found to be defective, replace the O2S sensor without wasting your time testing the O2S circuit. If necessary, you can perform the O2S circuit test with the new O2S sensor and save yourself some time.

1.

Locate the O2S sensor pigtail connector.

The heating circuit of the O2S sensor can be tested with a DMM set to measure resistance

2.


3.


4.

Using a DVO M set to read resistance (ohms), attach 1 DVO M test lead to the HPWR terminal, and the other lead to the HGND terminal, of the sensor pigtail connector, then observe the resistance readings. A.

If there is no continuity between the HPWR and HGND terminals, the sensor is defective. Replace it with a new one and retest.

B.

If there is continuity between the 2 terminals, b ut the resistance is greater than approximately 20 ohms, the sens or is defective. Replac e it with a new one and retest.

C.

If there is continuity between the 2 terminals and it is less than 20 ohms, the sensor is p robably not defective. Because of the large divers ity of engine control systems used in vehicles today, O2S sensor heating circuit resistance specifications change often. Generally, the amount of resistance an O2S sensor heating circuit should exhibit is between 2–9 ohms. However, some manufacturer's O2S sensors may show resistance as high as 15–20 ohms. As a rule of thumb, 20 ohms of resistance is the upper limit allowable.

NOTE: For the following step, the HO2S sensor should be approximately 75°F (23°C) for the proper resistance values.

5.

Turn the engine OFF, remove the DVOM and all associated jumper wires. Reattach the vehicle harness connector to the sensor pigtail connector.

6.


Bench Test NOTE: Utilize one of the in-vehicle tests before performing this test. This test is designed to test an O2S sensor which does not seem to fluctuate fully beyond 400–700 mV. The sensor is to be secured in a table-mounted vise. CAUTION This test can be very dangerous. Take the necessary precautions when working with a propane torch. Ensure that all combustible substances are removed from the work area and have a fire extinguisher ready at all times. Be sure to wear the appropriate protective clothing as well.

1.

Remove the O2S sens or. NOTE: Perform a visual inspection of the sensor. Black sooty deposits may indicate a rich air/fuel mixture, brown deposits may indicate an oil consumption problem, and white gritty deposits may indicate an internal coolant leak. All of these conditions can destroy a new sensor if not corrected before installation.

2.

Position the sensor in a vis e so that the vise holds the sensor by the hex portion of its case.

3.

Attach 1 lead of a DVO M set to read DC milliv oltages to the sensor case and the other lead to the SOUT terminal of the sensor pigtail connector.

4.

Carefully use a propane torch to heat the tip (and ONLY the tip) of the sens or. Once the sensor reaches c lose to normal operating temperature range, alternately heat the sens or up and allow it to cool down; the sensor output voltage signal should change with the temperature change. NOTE: This may also clean a sensor covered with a heavy coat of carbon.

5.

If the sensor voltage does not change with the fluctuation in temperature, repl ace the sens or with a new one. Install the new sensor and perform one of the in-vehicl e tests to rule out additional fuel management system faults.


1.

Start the engine and allow it to reach normal operating temperature, then turn the ignition switch OFF.

2.


3.

Op en the hood and locate the Oxygen (O 2S) sensor connector. It may be necess ary to raise and safely sup port the vehicle for access to the sensor and its connector. NOTE: On a few models, it may be necessary to remove the passenger seat and lift the carpeting in order to access the connector for a downstream O2S sensor. Since sensor locations vary between vehicles, the first step in removal is to locate the O2S sensors (arrows)...

... and the sensor connector (2), which is usually near the O2S sensor (1), but removed enough from the heat of the exhaust system

Disengage the sensor pigtail connector half from the vehicle harness connector half

For flange type sensors, loosen the hold-down fasteners...

... which happen to be nuts in this particular case — some models may use bolts rather than nuts

Then, pull the sensor out of the exhaust component

For screw-in type sensors (arrow)...

... either use a box end wrench to loosen the sensor or a socket designed expressly for this p urpose...

..., then remove the sensor from the exhaust component

4.

Dis engage the O2S sensor pigtail connector from the vehic le harness connector. NOTE: There are generally 2 methods used to mount an O2S sensor in the exhaust system: either the O2S sensor is threaded directly into the exhaust component (screw-in type) or the O2S sensor is retained by a flange and 2 nuts or bolts (flange type). WARNING To prevent damaging a screw-in type O2S sensor, if excessive force is needed to remove the sensor lubricate it with penetrating oil prior to removal. Also, be sure to protect the tip of the sensor. O2S sensor tips are very sensitive and may be easily damaged if allowed to strike or come in contact with other objects.

5.

Remove the sens or, as follows: Screw-in type sensors — O2S sensors are usually designed with a permanently attached wiring pigtail. This allows the wiring harness and sensor connectors to be positioned away from the hot exhaust system. It may be necessary to use a socket or wrench that is designed specifically for this purpose. Before purchasing such a socket, be sure that you can't save some money by using a box end wrench for sensor removal. Flange type sensors — Loosen the hold-down nuts or bolts and pull the sensor out of the exhaust component. Be sure to remove and discard the old sensor gasket, if equipped. You will need a new gasket for installation.

6.

Perform a visual ins pec tion of the sensor. Black sooty deposits may indic ate a rich air/fuel mixture, brown deposits may indicate an oil consump tion problem, and white gritty deposits may indicate an internal coolant leak. All of these conditions can destroy a new sensor if not corrected before installation.

7.

Install the sens or, as follows:

To install:

NOTE: A special anti-seize compound is used on most screw-in type O2S sensor threads, and is designed to ease O2S sensor removal. New sensors usually have the compound already applied to the threads. However, if installing the old O2S sensor or the new sensor did not come with compound, apply a thin coating of electrically-conductive anti-seize compound to the sensor threads. WARNING Be sure to prevent any of the anti-seize compound from coming in contact with the O2S sensor tip. Also, take precautions to protect the sensor tip from physical damage during installation. Screw-in type sensors — Install the sensor in the mounting boss, then tighten it securely. Flange type sensors — Position a new sensor gasket on the exhaust component and insert the sensor. Tighten the hold-down fasteners securely and evenly. 8.

Reattach the sens or pigtail connector to the vehic le harness connector.

9.

Lower the vehic le.

10.


11.

Start the engine and ensure no Diagnostic Trouble Codes (DTC's ) are set.


There are different locations in the exhaust system where O2S sensors are positioned. The locations have been given numbers and will be used in the accompanying charts to identify the positions of O2S sensors in most vehicles. Due to mid-year production changes or factory inconsistencies, all models may not be covered. If a vehicle being serviced is not covered in the charts, inspect the exhaust system (while cold!) in the general locations to find the applicable O2S sensors. NOTE: If equipped with dual exhaust systems, there may be up to 4 or 5 O2S sensors in the exhaust system. Be sure to locate all of them before commencing with any testing or service. Location No. 1 — down pipe or exhaust manifold

Location No. 1 — typical O2S sensor located in the exhaust manifold

Location No. 2 — left and right banks of a V-type engine

Location No. 3 — exhaust collector (where more than one pipe joins together)

Location No. 4 — outlet of the catalytic converter

Location No. 5 — inlet and outlet of the catalytic converter

Fig. 1: Location No. 6 — front, rear, left and right banks of a Vtype engine

Fig. 2: Location No. 7 — front, rear, inlet and outlet of the catalytic converter


Manual

Exploded view of the components associated with manual transmission removal and installation

1.

Before servi cing the vehic le, refer to the prec autions in the beginning of this section.

2.


3.

Supp ort the transmiss ion with a jack and remove the transmis sion sup port assem bly (19).

4.

Remove or disc onnect the following: Exhaust support bracket (10) and U-bolt (11) Heat shield (5) Front driveshaft (71) Exhaust system (60) at the rear mount. Use a piece of wire to suspend it Speedometer cable (9) or Vehicle Speed Sensor (VSS) (85a) Clutch hydraulic line (arrow) Shift linkage clips (32) and shift linkage Transmission ground strap (27) Transmiss ion-to-engine mounting b olts Transmission To install:

5.

App ly a light coating of grease to the sp lines of the input shaft (33 ).

6.

Lift the transmis sion to the engine.

7.

Install or connect the following: Transmission mounting bolts Ground strap Shift linkage Clutch hy draulic line Speedometer cable or VSS Exhaust system with new gaskets Driveshaft Heat shield Exhaust support bracket and U-bolt Transmission supp ort

8.

Check the transmis sion oil level and add if neces sary.

9.

Lower the vehic le to the floor and connect the negative battery cabl e. Bleed the hydraulic c lutch sys tem.

AutoMatic

Exploded view of the components associated with autoMatic transmission removal and installation

1.


2.

Remove or disc onnect the following: Negative b attery c able Radiator fan shroud Dips tick tube (61) and transmission fluid Electrical connector shield (62) Electrical connector

Park interlock cable (80) NOTE: Be sure the transmission selector lever is in PARK before removing the cable. 3.

Remove or disc onnect the following: Torque converter cover (81) Torque converter-to-flexp late bolts Oil cooler lines Shift rod (63) Exhaust mounting bracket (64) Exhaust system (94) Rear transmission mount (65) Front half of rear driveshaft (66) Transfer case driveshaft if equipped with 4-MATIC Ground strap (46) Transmiss ion-to-engine mounting b olts Transmission To install:

4.

Position the transmis sion on the engine and install the mounting bolts.

5.

Install or connect the following:

6.

Ground strap

7.

Front half of rear drives haft

8.

Transfer cas e drives haft if equipp ed with 4-MATIC

9.

Rear transmis sion mount

10.

Exhaust sys tem

11.

Exhaust mounting brac ket

12.

Shift rod

13.

Oil cooler lines

14.

Torque converter-to-flexp late bolts to 31 ft. lbs . (42 Nm)

15.

Torque converter cover

16.

Park interlock cable

17.

Electrical connector and shield

18.

Transmission dipstick tube

19.

Fan shroud

20.

Negative battery cable

21.

Transmiss ion fluid


All clutch release mechanisms are hydraulic, no periodic adjustment is necessary.


1.


2.

Remove or disc onnect the following: Transmission assemb ly Pressure plate (6) mounting bolts (9)

3.

Inspect the pilot bearing, release bearing (7), release fork (8) and flywheel. Replace as necessary.

4.

Deglaze the flywheel with coarse abras ive cloth.

5.


To install:

Clutch disc using a line-up tool (012) Pressure plate. Torque the mounting bolts to 18 ft. lbs. (25 Nm) 6.

Lightly grease the friction surfaces (arrows) on the release fork. Install the transmiss ion ass embly l ower the vehicle and check operation. Exploded view of the clutch assembly


1.


2.

Fill the reservoir with brak e fluid. Do not allow brak e fluid to contact painted surfaces.

3.

Have a helper push the clutch pedal down and hold it.

4.

Attach a clear plastic hose to the bleeder valve. Plac e the other end of the hose in a container to catch the brake fluid.

5.

Op en the bleeder valv e on the release cy linder to exp el air, then close the bleeder valve. Do not release the clutch pedal until the bleeder valve is cl osed.

6.

Repeat the procedure until clear fluid flows out of the bleeder valv e.


1.


2.

Drain the fluid and remove the exhaust brackets . Susp end the exhaust with a piec e of wire.

3.

Remove or disc onnect the following: Driveshaft shield Case bracket Case vibration damper Front half of rear driveshaft

4.

Supp ort the transmis sion and remove the engine support along with the rear engine mount. Lower the assemb ly sli ghtly.

5.

Remove or disc onnect the following: Front driveshaft Transfer case bolts

6.

Remove the transfer case and drain the residual oil.

7.


To install:

Transfer case with new gasket. Torque the bolts to 22 ft. lbs. (30 Nm) Rear engine support. Torque the bolts to 30 ft. lbs. (40 Nm) Driveshafts. Torque the bolts to 18 ft. lbs. (25 Nm) Case vibration damper Driveshaft shield Exhaust brackets


Front (4-Matic)

1.


2.

Remove or disc onnect the following: Negative b attery c able Front wheel 12-pointed axle nut (61) Engine undercover Brake hose bracket (arrow) Stabilizer bar brackets (22b) Headlight leveling linkage (80 ) Lower ball joint (7) from the steering knuckle (5). Shock absorber (11) from the lower control arm (4) Lower control arm mounting bolts Halfshaft To install:

3.

Install or connect the following: Halfshaft Lower ball joint Shock absorber Headlight leveling linkage Stabilizer bar brackets Brake hose bracket Engine undercover 12-pointed axle nut. Torque the nut to 162 ft. lbs. (220 Nm) Front wheel Negative b attery c able Exploded v iew of the front halfshaft mounted — 4-Matic

Rear

1.


2.

Remove or disc onnect the following: Wheel Center axle hold-down bolt (in hub) Brake caliper. Suspend it with a wire

3.

Drain the differential oil and sup port the differential housing.

4.

Remove or disc onnect the following: Differential housing cover Axle lock ring Axle shaft. If necessary, loosen the shock ab sorber To install:

5.

Install or connect the following: Axle shaft. Torque the nut to 148–175 ft. lbs. (200240 Nm) Axle lock ring Differential housing cover Brake caliper Center axle hold down bolt Wheel

6.

Fill the axle with oil. New radial seal rings are used on all models. Lubricate the outside diameter of radial sealing rings with hyp oid gear lubri cant prior to installation. NOTE: Check end-play of the lock ring in the groove. If necessary, install a thicker lock ring or spacer to eliminate all end-play, while still allowing the

lock ring to rotate. Do not allow the joints in the axle shaft to hang free or the joint bearing may be damaged.


Front (4-Matic)

1.


2.

Remove or disc onnect the following: Axle shaft Rubber boot sealing clamp and CV-joint circlip

3.

Using a soft metal drift or a piece of wood, tap the CV-joint off the shaft.

4.

Use a rag to clean off the grease, ins pec t all components for wear and/or damage and replace as neces sary. To install:

5.

Replac e the rubber boot and install the CV-joint and circlip . Replac e the grease with the app ropriate CV-joint lubri cant.

6.

Install the axle assembly.

Rear

1.


2.

Remove or disc onnect the following: Axle shaft End cover and boot cap Rubber boot sealing clamp CV-joint locking ring

3.

Remove the CV-joint from the axle using a press. Remove the rubb er boot.

4.

Use a rag to clean off the grease, ins pec t all components for wear and/or damage and replace as neces sary.

5.

Replac e the rubber boot and install the CV-joint using a press. Replac e the grease with the appropriate CV-joint lubri cant.

6.


To install:

CV-joint locking ring Rubber boot sealing clamp End cover and boot cap Axle shaft


Front (4-Matic)

1.


2.

Remove or disc onnect the following: Steering knuck le Axle shaft flange using an appropriate puller Bearing circlip Bearing using appropriate removal tool To install:

3.

Install or connect the following: Bearing using appropriate installation tool Bearing circlip Axle shaft flange using appropriate installation tool Steering knuck le

Rear

1.


2.

Remove or disc onnect the following: Axle shaft Disc brake rotor Axle shaft Wheel bearing locking ring Wheel bearing using an ap propriate puller To install:

3.

Install or connect the following: Wheel bearing using appropriate installation tool Wheel bearing locking ring Axle shaft flange using appropriate installation tool Disc brake rotor Axle shaft


Exploded view of the components associated with the front drive pinion (4-MATIC)

Front (4-Matic)

1.


2.

Remove or disc onnect the following: Axle shaft Drive p inion with bearing cover

3.

Mark the bearing cover relative to the front axle drive housing.

4.

Remove or disc onnect the following: Rubber O-ring Pinion seal To install:

5.

Coat the pini on seal lip and the rubb er O-ring with clean hyp oid transmiss ion oil.

6.

Install or connect the following: Pinion seal O-ring Bearing cover. Torque the bolts to 26 ft. lbs. (35 Nm) Drive pinion and flange with new self-locking hexagon collar nut. Torque the nut to 350 ft. lbs. (475 Nm). Axle shaft.

Rear

1.


2.

Remove or disc onnect the following: Exhaust system Driveshaft Fuel pump cover Driveshaft intermediate bearing Driveshaft at differential Rear axle shafts at connecting flange 12-point hexagon collared nut Pinion flange using appropriate puller Rubber O-ring Pinion seal To install:

3.

Coat the pini on seal lip and the rubb er O-ring with clean hyp oid transmiss ion oil.

4.

Install or connect the following: Pinion seal Rubber O-ring Drive pinion and flange with new self-locking hexagon collared nut. Torque the nut to 133 ft. lbs. (180 Nm)

5.

Install or connect the following: Rear axle shafts Driveshaft at differential Driveshaft intermediate bearing. Torque the bolts to 22 ft. lbs. (30 Nm) Fuel pump cover Exhaust system


Front (4-Matic)

1.


2.

Remove or disc onnect the following: Electrical connections Axle shafts Shock absorbers and front springs Steering knuck les

3.

Supp ort the engine and remove the front mount. Drain the power steering fluid.

4.

Remove or disc onnect the following: Feed line from reservoir if equipped with level control Steering shaft Power steering lines at steering gear Headlamp leveling wiring harness Front axle carrier bolts Front axle assemb ly from vehicle To install:

5.

Install or connect the following: Axle assemb ly. Torque the carrier bolts to 96 ft. lbs. (130 Nm) Headlamp leveling wiring harness Power steering lines at steering gear Steering shaft Feed line from reservoir if equipped with level control Engine mount. Torque the bolt to 26 ft. lbs. (35 Nm) Axle shafts Steering knuck les Shock absorbers and front springs Electrical connections

Rear

1.


2.

Drain the differential oil.

3.

Remove or disc onnect the following: Axle shafts Exhaust system Driveshaft intermediate bearing Driveshaft

4.

Supp ort the rear axle housing ass embly

5.

Remove or disc onnect the following: Axle housing suspension mountings Axle housing assemb ly To install:

6.

Install or connect the following: Axle housing assemb ly Axle housing suspension mountings Driveshaft Driveshaft intermediate bearing. Torque the bolts to 22 ft. lbs. (30 Nm) Exhaust system Axle shafts


2.8L, 3.2L and 3.6L (104) Engines

1.


2.

Properly recover the air conditioning sy stem refrigerant.

3.

Properly relieve the fuel sys tem pressure.

4.

Drain the engine coolant and engine oil.

5.

Remove or disc onnect the following: Negative b attery c able Exhaust Steering damper AutoMatic transmission cooling lines Coolant expansion reservoir Cooling fan and radiator

6.

Cover the air conditioning condenser using a piece of sheet metal, ply wood or plastic .

7.

Remove or disc onnect the following: Charge air pip es Air cleaner housing Power steering lines Power steering pump Fuel lines Engine wiring harness and vacuum lines Throttle cab le Coolant hoses Rear engine mount Driveshaft Park lock interlock cable AutoMatic transmission control unit connector Transmission linkage Front engine mounts

8.

Raise the engine sufficiently until bolts of air conditioning compres sor are acces sib le

9.

Remove or disc onnect the following: Air conditioning compressor Engine assemb ly To install:

10.

Install or connect the following: Engine assemb ly Engine mounts. Torque the bolts to 41 ft. lbs. (55 Nm) Air conditioning compressor Transmission linkage AutoMatic transmission control unit connector Park lock interlock cable Driveshaft Coolant hoses Throttle cab le Engine wiring harness and vacuum lines Fuel lines Power steering pump and lines Air cleaner housing Charge air pip es

11.

Remove the air conditioning condenser guard

12.

Install or connect the following: Cooling fan and radiator Coolant expansion reservoir AutoMatic transmission cooling lines Steering damper Exhaust Negative b attery c able Coolant Transmission fluid Refrigerant

2.2L and 2.3L (111) Engines

1.


2.

Properly recover the air conditioning sy stem refrigerant.

3.


4.

Drain the engine coolant, engine and transmiss ion oil.

9.

Supp ort the transmiss ion ass embl y and lift the engine out of the vehic le. To install:

10.

Position the engine assembl y into the vehicle and install the mounts. Torque the bolts to 18 ft. lbs . (25 Nm)

11.

Install or connec t the following: Rear engine crossmember. Torque the bolts to 30 ft. lbs. (40 Nm) Transmission linkage Driveshaft Starter Exhaust system Oil pressure switch Air conditioning compressor Oil cooler lines Power steering pump Wiring, vacuum and cable connections Fuel lines Fuel lines Access ory drive belts Fan shroud, clutch and fan assemb ly

12.

Remove the air conditioning condenser guard and fill the power steering reservoir.

13.

Install or connect the following: AutoMatic transmission fluid lines Radiator and coolant hoses Air cleaner Negative b attery c able Coolant Engine oil Transmission fluid


All Models

1.


2.

Dis connect the negative battery cable and drain the cooling sy stem.

3.

Remove or disc onnect the following: Fan clutch, fan and shroud Engine cover if equipped Access ory drive belt and tensioner Secondary air injection switchover valve if equipped Power steering pump. Position the pump aside, leaving the hoses attached Water pump coolant hoses Oil-to-water heat exchanger coolant hoses if equipped Belt pulley Water pump mounting bolts Water pump

4.

Clean all gasket material from the sealing surfaces. Exploded view of the water pump mounting — 3.2L (112) and 4.3L (113) engines

Exploded view of the water pump mounting — 2.2L and 2.3L (111) engine

Exploded view of the water pump mounting — 2.8L and 3.2L, (104) engines in the SL

Exploded view of the water pump mounting — 2.8L, 3.2L and 3.6L (104) engine in the C and E Class models

Exploded view of the water pump mounting — 4.2L and 5.0L

(119) engines

Water pump mounting bolt identification — 4.2L and 5.0L (119) engines

To install: 5.

Install the water pump and gasket. Torque the bolts as follows: 2.8L, 3.2L, 3.6L (104) and 4.2L, 5.0L (119) engines: 15 ft. lbs. (21 Nm) 2.2L and 2.3L (111) engines: M6 bolts to 88 inch lbs. (10 Nm). M8 bolts to 18 ft. lbs. (25 Nm) 3.2L (112) and 4.3 (113) engines: M6 bolts to 88 inch lbs. (10 Nm). M8 bolts to 15 ft. lbs. (20 Nm) 6.0L (120) engine: M6 bolts to 88 inch lbs. M8 bolts to 15 ft. lbs. (21 Nm)

6.

Install or connect the following: Belt pulley. Torque the mounting bolts to 88 inch lbs. (10 Nm) Oil-to-water heat exchanger coolant hoses Water pump coolant hoses Power steering pump Secondary air injection switchover valve Access ory drive belt and tensioner Fan clutch, fan and shroud Engine cover Coolant Negative b attery c able


2.8L, 3.2L and 3.6L (104) Engine NOTE: Cylinder head tightening illustrations are located in Section 1 of this manual. The illustrations follow the Torque Charts.

1.


2.

Properly relieve the fuel sy stem pressure and drain the engine c oolant.

3.

Position the No. 1 cy linder at TDC.

4.

Remove or disc onnect the following: Negative b attery c able Coolant hoses Upper timing cover

5.

Matchmark the camshaft sprock et to the timing chain, and remove the pin (1) for the timing chain guide with a threaded extractor.

6.

Remove or disc onnect the following: Guide sprocket (left-hand thread) Bearing assembly Timing chain from the camshaft sprockets. Wire the chain aside NOTE: Be sure the chain is securely wired so it will not slide into the engine.

7.

Remove or disc onnect the following: Vacuum hoses and electrical connectors Exhaust system Secondary air injection pipe if equipp ed Dipstick tube support bracket Crankcase breather hose Fuel lines Dipstick tube Throttle, kickdown and cruise control cables

8.

Loosen the head bolts in stages in the reverse order of the illus trated sequenc e. CAUTION Never use a prybar between the head and the block.

9. 10.

Remove the cylinder head and clean all gasket material from the sealing surfac es. Be sure the cylinder head locating dowels are positioned correctly in the engine block . Inspec t length of the cy linder head bolt shaft. New bolt length is 6.30 inc hes (160mm), and the maximum permis sib le length is 6.44 inches (163 .5mm). Replac e bolts that measure greater than the maximum permissible length. To install: NOTE: The head will not be watertight until the engine reaches operating temperature. Do not pressure test the cooling system until the engine has reached operating temperature. Cylinder head gasket identification — 2.8L 3.2L and 3.6L (104) Engines

11.

Rotate the camshafts so that the bottom edge of the holes in the c amshaft flange, are level with the top edge of the cylinder head. Verify the correct position of the camshafts for cylinder head installation using a 4mm pin (1) — 2.8L 3.2L and 3.6L (104) Engines

12.

Verify the TDC position of the No. 1 cylinder. Clean the head bolt threads, and then app ly c lean engine oil to the thread and head contact surfaces .

13.

Install the head gask et and cy linder head.

14.

Torque the head bolts using the illus trated sequence to 41 ft. lbs. (55 Nm) plus 90 degrees, then an additional 90 degrees .

15.

Install or connect the following: Timing chain and upper timing chain guide

Timing chain guide pin Guide sprocket and bearing assembly. Torque the bolt to 26 ft. lbs. (35 Nm) Throttle, kickdown and cruise control cables Fuel lines Crankcase breather hose Oil dipstick tube Secondary air injection pipe if equipp ed Exhaust system Vacuum hoses and electrical connectors Coolant hoses Coolant Negative b attery c able

2.2L and 2.3L (111) Engines NOTE: Cylinder head tightening illustrations are located in Section 1 of this manual. The illustrations follow the Torque Charts.

1.


2.

Drain the engine coolant.

3.

Remove or disc onnect the following: Negative b attery c able Exhaust system and b racket at transmission Thermostat housing c over Air intake tubes Electrical connectors Coolant hose (3) at the rear of the cylinder head Intake manifold (19). Position it aside Crankcase breather hose Manifold bracket (2) Valve cover Thermostat housing Cylinder head front cover HO2S sensor connector Engine and transmiss ion dipstick guide tubes (7) (8)

4.

Position crank shaft to 20–3 0 degrees ATDC for cylinder No. 1.

5.

Lock the camshafts (75 and 78 ) with locking pins (01) and matchmark the timing chain to the sp rockets.

6.

Remove or disc onnect the following: Chain tensioner (14) Chain guide rail in the cylinder head Exhaust camshaft sprocket (76) Intake camshaft sprocket (74)

7.

Install the cy linder head removal brac ket (16) and remove the guide rail pin (11), using a threaded extractor.

8.

Remove or disc onnect the following: Timing chain housing bolts (A) Cylinder head bolts in the reverse order of the illustrated tightening sequence CAUTION Never use a p rybar b etween the head and block.

9. 10.

Remove the cylinder head and clean all gasket material from the sealing surfac es. Be sure the cylinder head locating dowels are positioned correctly in the engine block . Inspec t length of the cylinder head bolt shaft. New bolt length is 102mm and the maximum permis sib le length is 105mm . Replac e bolts that measure greater than the maxim um permissib le length. To install: Exploded view of the cylinder head accessory components — 2.2L and 2.3L (111) engines

Exploded view of the cylinder head mounting — 2.2L and 2.3L (111) engines

NOTE: The head gasket is not watertight until the engine has reached operating temperature. Do not pressure test the cooling system until the engine has reached operating temperature.

11.

Verify the TDC position of the No. 1 cylinder. Clean the head bolt threads and app ly cl ean engine oil to the thread and head contact surfaces.

12.

Install or connect the following: Head gasket and cylinder head. Torque the head bolts using the illustrated sequence to 41 ft. lbs. (55 Nm) plus 90 degrees, then an additional 90 degrees Timing chain housing bolts Guide rail pin

13.

Remove the cy linder head removal brac ket.

14.

Install or connect the following: Intake and exhaust camshaft sprockets Guide rail Chain tensioner

15.

Remove the cams haft locking pins and verify timing mark alignment.

16.

Install or connect the following: Engine oil and transmission dipstick guide tubes HO2S sensor Cylinder head front cover Thermostat housing Valve cover Cylinder head coolant hose Crankcase breather hose Intake manifold Electrical connectors Thermostat housing cover and air intake tubes Exhaust system and bracket Coolant Negative b attery c able

3.2L (112) and 4.3L (113) Engines NOTE: Cylinder head tightening illustrations are located in Section 1 of this manual. The illustrations follow the Torque Charts.

1.


2.

Properly reliev e the fuel system p ressure and drain the engine coolant. Place a guard plate behind the radiator/condenser to protect it from damage.

3.

Remove or disc onnect the following: Negative b attery c able Fan clutch, fan and shroud Engine cover Air cleaner housing, resonance pip e and body Fuel line Ignition c oils Cylinder head covers NOTE: The intake manifold system must not be disassembled.

4.

Remove or disc onnect the following: Intake manifold Vacuum switchover v alve Camshaft Position (CMP) sensor

5.

Lock the autoMatic b elt tensioner by rotating the tensioner counterclockwise until a 5mm drift or pin fits through the tensioner, and then remove the serp entine belt.

6.

Remove or disc onnect the following: Power steering pump. Position it aside leaving the hoses attached Serpentine b elt Heater hose at the firewall Exhaust system

7.

Rotate the engine clockwis e to position the crankshaft 40 degrees ATDC. WARNING The engine must not be rotated backwards.

8.

Lock the cams hafts using cams haft locking tools.

9.

Remove or disc onnect the following: Generator Timing chain tensioner Camshaft gears. Attach to the chain with a cable tie Camshaft bearing bridges Camshafts Timing case-to-cylinder head bolts Cylinder head bolts in the reverse order of the illustrated sequence CAUTION Never use a p rybar b etween the head and block.

10.

Remove the cylinder head and clean all gasket material from the sealing surfac es. Be sure the cylinder head locating dowels are positioned in the engine block .

11.

Inspec t length of the cylinder head bolt shaft. New bolt length is 141.5mm and the maximum permis sib le length is 144.5mm. Replac e bolts that measure greater than the maximum permissib le length. Exploded view of the cylinder head accessory components — 3.2L (112) engine shown

Exploded view of the cylinder head removal — 3.2L (112) engine shown

To install: 12.

Clean the head bolt threads and app ly clean engine oil to the thread and head contact surfaces.

13.

Install the cy linder head gasket and head. Torque the head bolts according to the illustrated sequence as follows: Step 1: 15 ft. lbs. (20 Nm) Step 2: 37 ft. lbs. (50 Nm) Step 3: 60–70 degrees Step 4: Additional 60–70 degrees

14.

Install or connect the following: Timing case-to-cylinder head bolts. Torque to 15 ft. lbs. (20 Nm) Camshafts Camshaft bearing bridges Camshaft gear. Torque the mounting bolt to 37 ft. lbs. (50 Nm) plus an additional 90 degrees Timing chain tensioner with new gasket. Torque to 59 ft. lbs. (80 Nm) Generator

15.

Remove the cams haft locking plates.

16.

Install or connect the following: Exhaust system. Torque mounting nuts to 15 ft. lbs. (20 Nm) Heater hose Power steering pump Serpentine b elt CMP sensor Vacuum switchover v alve Intake manifold Cylinder head covers. Torque the bolts to 88 inch lbs. (10 Nm) Ignition coils. Torque the mounting bolts to 70 inch lbs. (8 Nm) Fuel line Air cleaner housing, resonance pip e and body Engine cover Fan clutch, fan and shroud

17.

Remove the guard plate from the radiator/condenser.

18.

Fill the cooling sy stem, connect the negative battery cab le, start the engine and chec k for leaks.

4.2L and 5.0L (119) Engines NOTE: Cylinder head tightening illustrations are located in Section 1 of this manual. The illustrations follow the Torque Charts.

1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Engine cover Front covers

4.

Crank the No. 1 piston of the engine to 45 degrees BTDC. Look for the 4/5 on the timing indicator.

5.

Mark all 4 cams haft timing gears and timing chain with colored dots at about 11 o'c lock for the right outer and left inner camshaft sprock et and 1 o'clock for the right inner and left outer camshaft sprocket.

6.

Remove or disc onnect the following: Timing chain tensioner and top guide rails

Camshaft gears and adjusters Electrical wiring, hoses and c ables Intake manifold Dipstick guide tube Exhaust pipes and manifolds Cylinder head covers NOTE: Be sure the engine is c old b efore removing cylinder head b olts. On the "close-d eck" crankcase, the cylinder head b olts have different lengths. 7.

Loosen the cy linder head bolts in the reverse order of the illus trated tightening sequenc e.

8.

Remove the cylinder head and clean all gasket material from the sealing surfac es. Be sure the cylinder head locating dowels are positioned in the engine block .

9.

Inspec t length of the cylinder head bolts. New bolt length is 160mm and the maximum permis sib le length is 163.5mm. Replac e bolts that measure greater than the maxim um permissib le length. To install: NOTE: The head gasket is not watertight until the engine has reached operating temperature. Do not pressure test the cooling system until the engine has reached operating temperature.

10.

Clean the head bolt threads, and then apply c lean engine oil to the thread and head contact surfaces.

11.

Install the cy linder head gasket and head. Torque the bolts in sequence, as follows: 41 ft. lbs. (55 Nm) + 90 degrees + additional 90 degrees Torque the M8 bolts near the timing sprockets to 18 ft. lbs. (25 Nm) NOTE: Bolts that are screwed into the front of the cylinder head must be coated with sealant when installed.

12.

Install or connect the following: Cylinder head covers Exhaust pipes and manifolds Dipstick guide tube Intake manifold Wiring, hoses and c ables Camshaft gears and adjusters Timing chain tensioner and top guide rails Front covers Engine cover Coolant Engine oil Negative b attery c able

6.0L (120) Engines NOTE: Cylinder head tightening illustrations are located in Section 1 of this manual. The illustrations follow the Torque Charts.

1.


2.

Drain the cooling sy stem.

3.

Remove or disc onnect the following:

4.

Negative battery cab le

5.

Intake manifold

6.

Engine ass embly on S models

7.

Exhaust pip es and brac ket on SL models

8.

Valve covers

9.

Rotate the cranks haft to 30 degrees ATDC.

10.

Matchmark the cams haft sp rockets to the timing chain as illus trated. Matchmark the timing chain and sprockets for installation — 6.0L (120) engines

11.

Remove or disc onnect the following: Timing chain tensioner Timing chain from camshaft sprockets Left head ventilation tube Transmission dipstick tube Oil dipstick tube Timing chain guide rails Secondary air injection lines Exhaust manifold on S models Coolant hose at the rear of the head

12.

Loosen the head bolts in stages, in the reverse of the tightening sequence. Remove the cyli nder heads with the exhaust manifolds attached. Clean all gasket material from the sealing surfaces. Be sure the cylinder head locating dowels are positioned in the engine block.

13.

Measure the cy linder head bolts. New bolts are 168mm long, and the maximum allowable length is 171mm . Replac e any bolts that exceed the maxim um length. To install:

NOTE: The head gasket is not watertight until the engine has reached operating temperature. Do not pressure test the cooling system until the engine has reached operating temperature. 14.

Install the cy linder head gask et and head. Torque the bolts in sequence, as follows: 41 ft. lbs. (55Nm). + 90 degrees. + another 90 degrees.

15.

Install or connect the following: Coolant hose Exhaust manifold on S models Secondary air injection lines Timing chain guide rails Oil dipstick tube Transmission dipstick tube Ventilation tube

16.

Align the matchmarks and install the timing chain.

17.

Install or connect the following: Timing chain tensioner. Verify the correct valve timing Valve covers Engine assembly on S models For SL models, connect the exhaust pipes to the manifolds and connect the exhaust pipe bracket to the transmission Intake manifold Engine oil Coolant Negative b attery c able


All engines except the 112 and 113 are not equipped with rocker arms/shafts. The camshaft(s) act directly on valve tappets. On the 112 and 113 engines, the rocker arm/shaft is part of the camshaft bearing cap assembly and is called the camshaft bearing bridge. This procedure is for removing and installing the camshaft bearing bridge.

3.2L (112) and 4.3L (113) Engines

1.


2.

Remove or disc onnect the following: Negative b attery c able Cylinder head cover

3.

Rotate the engine clock wise to position the crankshaft 40 degrees after top dead center. WARNING The engine must not be rotated backwards.

4.

Remove or disc onnect the following: Generator Timing chain tensioner

5.

Cable tie the timing chain to the cams haft sp rockets and remove the sp rockets.

6.

Loosen the cams haft bearing bridge bolts in reverse of the illus trated sequence. NOTE: The camshaft bearing bridge must not be disassembled. If damage exists at the valve gear or at the top half of the camshaft bearing journal, the complete cylinder head should be replaced. To install:

7.

Lubric ate the cams haft bearing journals.

8.

Install or connect the following: Camshaft bearing bridge. Torque the bolts to 11 ft. lbs. (15 Nm) in sequence as illustrated Camshaft sprockets Timing chain tensioner with new gasket. Torque to 59 ft. lbs. (80 Nm) Cylinder head covers. Torque to 88 inch lbs. (10 Nm)

9.

Connect the negative battery cab le, start the vehic le and chec k operation.


1.


2.


3.

Remove or disc onnect the following: Intake air assembly. Plug supercharger openings Sensor block cover Electromagnetic clutch connector Coolant hose, radiator to water pump Coolant return hose Fan and shroud Supercharger drive belt Supercharger pressure connections Supercharger To install: NOTE: Install the bottom securing bolt in the supercharger before installing.

4.

Install or connect the following: Superc harger. Torque the mounting b olts to 16 ft. lbs . (21 Nm) Pressure connections with new seals Drive belt Fan and shroud Coolant hoses Electromagnetic clutch connector Sensor block cover

5.

Remove the plug from the inlet of the sup ercharger and install the intake air ass embl y.

6.

Fill the cooling sy stem, start the engine and chec k operation.


2.8L 3.2L and 3.6L (104) Engines

1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Vacuum, electrical and cable connectors Fuel rail with the injectors Resonance intake manifold (throttle body). Clean the gasket surfaces Intake manifold To install: Exploded view of the intake manifold mounting and related components — 2.8L, 3.2L and 3.6L (104) engines

4.

Clean all gasket material from the sealing surfac es. Install intake manifold gaskets and manifold. Torque the mounting bolts to 18 ft. lbs. (25 Nm).

5.

Install or connect the following: Resonance intake manifold with new gaskets Fuel rail with new injector seals Vacuum, electrical and cable connectors

6.

Check and adjust the throttle linkage.

7.

Connect the negative battery cab le, start the engine and chec k for leaks .


1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Intake air cross pip e Ignition coils if necessary Power steering pump bracket mounting bolt if necessary Fuel rail with injectors Intake manifold support bracket Vacuum, electrical and cable connectors Manifold mounting nuts and bolts Intake manifold To install: Exploded view of the intake manifold mounting and related components — 1997–00 2.2L and 2.3L (111) engines

4.

Clean all gasket material from the sealing surfac es. Install the manifold gask ets and intake manifold. Torque the mounting bolts and nuts to 15 ft. lbs . (20 Nm).

5.

Install or connect the following: Vacuum, electrical and cable connectors Intake manifold support bracket Fuel rail with new injector seals Power steering pump bracket mounting Ignition c oils Intake air cross pip e

6.

Check and adjust the throttle linkage.

7.

Connect the negative battery cab le, start the engine and chec k for leaks .

3.2L (112) and 4.3L (113) Engines

1.


2.

Remove or disc onnect the following: Negative b attery c able Cylinder head cover MAF sensor with intake pi pe

3.


4.

Remove or disc onnect the following: Fuel rail with injectors Vacuum, electrical and cable connectors EGR valve Combination valve Manifold mounting b olts Intake manifold Exploded view of the intake manifold mounting and related components — 3.2L (112) engine shown.

To install: 5.

Clean all gasket material from the sealing s urfaces. Install the new intake manifold gasket. Verify the secondary air injection pass age opening in the gasket and install the intake manifold. Torque the mounting b olts to 15 ft. lbs . (20 Nm).

6.

Install or connect the following: Combination valve. Torque the bolts to 15 ft. lbs. (20 Nm) EGR valve Vacuum, electrical and cable connectors Fuel rail with new injector seals MAF sensor with the air intake pipe Cylinder head cover. Torque the bolts to 88 inch lbs. (10 Nm)

7.

Reconnect the negative battery cab le, start the vehic le and chec k for leaks .


Exploded view of the intake manifold mounting and related components — 4.2L and 5.0L (119) engines

1.


2.

Partially drain the coolant.

3.

Remove or disc onnect the following: Negative b attery c able Air cleaner and engine cover Vacuum and electrical connectors

4.


5.

Remove or disc onnect the following: Fuel supply (17/3) and return (17/2) lines Guide element (27) Throttle cable (30) at the control lever (9) Control p ressure cabl e (98 ) Accelerator actuator (M16/1x1) connector and cable Coolant hose (33) at the front of the manifold Coolant hose at the rear of the manifold Manifold mounting b olts Intake manifold To install:

6.

Clean all gasket material from the sealing surfaces.

7.

Install or connect the following: Manifold gasket and intake manifold. Torque the bolts in sequence to 18 ft. lbs. (25 Nm). Coolant hoses Accelerator actuator connector and cable Control pressure cable Throttle and transmission cables Guide element Fuel lines Vacuum, electrical and cable connectors Air cleaner and engine cover Engine oil Coolant Negative b attery c able

6.0L (120) Engines

1.


2.

Partially drain the coolant.

3.

Remove or disc onnect the following: Negative b attery c able Air cleaner and engine cover Vacuum, electrical and cable connectors

4.


5.

Remove or disc onnect the following: Fuel supp ly and return lines Electronic acc elerator actuator Throttle body Air inlet plenum chamber if equipped Manifold mounting b olts Intake manifold Intermediate flanges Exploded view of the intake manifold — 6.0L (120) engines

To install: 6.

Replac e the shap ed rubb er seals and install the intermediate flanges with new gask ets.

7.

Clean all gasket material from the sealing surfaces.

8.

Install or connect the following: Manifold gasket and intake manifold Air intake plenum chamber Throttle body Electronic acc elerator actuator Fuel lines Vacuum, electrical and cable connectors Air cleaner and engine cover Engine oil Coolant Negative b attery c able


Inline 4- and 6-Cylinder Engines

1.


2.

Remove or disc onnect the following: Negative b attery c able Exhaust pipe Transmission exhaust sup port if equipped Air injection tube if equipped Manifold retaining bolts and manifold To install: Exploded view of the mounting — 4-cylinder shown, inline 6cylinder similar

3.

Install or connect the following: Manifold gasket and exhaust manifold. Torque the bolts in an even pattern Air injection tube Transmission exhaust supp ort Exhaust pipe with new self-locking nuts. Torque to 25 ft. lbs. (34 Nm) Negative b attery c able

V6, V8, and 12-Cylinder Engines

1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Engine undercover Exhaust pipes Fan shroud. Engine mount for the manifold being serviced Fuel supply and return pipes if removing left manifold Self-locking bolts and exhaust manifold To install:

4.

Inspec t the rivet nuts in the manifold and replac e as needed.

5.

Install or connect the following: Manifold gasket and exhaust manifold. Torque the mounting bolts to 23 ft. lbs. (30 Nm) Fuel lines if removed Engine mounts Fan shroud. Exhaust pipes Engine under cover

6.

Connect the negative battery cab le, start the engine and chec k for leaks.


2.8L, 3.2L and 3.6L (104) Engines

1.

Before servi cing the vehic le, refer to the precautions in the beginning of this section.

2.

Dis connect the negative battery cab le and position the No. 1 cy linder 30 degrees BTDC.

3.

Remove or disc onnect the following: Valve cover Timing chain tensioner (1) Upper front cover (30) and top guide rail (42)

4.

Matchmark the timing chain (6) to the cams haft sp rockets (3 and 5).

5.

Remove or disc onnect the following: Exhaust camshaft sprocket (3) Timing chain from the intake camshaft (5)

6.

Hold the camshafts so that the lobes of the cams of cy linder No. 2 press on the middle of the buck ets. Unbolt the camshaft bearing caps 1, 4, 6 and 7 of the exhaust camshaft (14) and 8, 11, 13 and 14 of the intake camshaft (13). Loosen the remaining bearing cap bolts 1 turn at a time until there is no counterpressure.

7.

Remove or disc onnect the following: Camshafts Bucket tappets Position the crankshaft as shown to prevent piston-to-valve contact — 2.8L, 3.2L and 3.6L (104) engines

Remove the indicated bearing caps first — 2.8L, 3.2L and 3.6L (104) engines

To install: 8.

Install the buc ket tappets and oil the cams haft journals and lobes . Install the camshafts at 30 degrees BTDC for cyli nder No. 1. The lobes of the cams must be facing on the middle of the buckets for cylinder No. 2. Be sure to install the indicated bearing caps first — 2.8L, 3.2L and 3.6L (104) engines

9.

Bearing cap s 2, 3 and 5 for the exhaust cams haft and 9, 10 and 12 for the intake cams haft. Torque to 15 ft. lbs . (21 Nm). Hold the camshafts s o that the lobes of the cams of cylinder No. 2 press on the middle of the buckets. Install the remaining bearing caps. Torque to 16 ft. lbs. (22 Nm).

10.


11.

Timing chain

12.

Exhaust cams haft sp rocket

13.

Align the matchmarks and install the sp rocket. Torque to the following spec ification: M7 13.5mm T30 Torx® bolt: 13 ft. lbs. (18 Nm) M7 13.5mm T40 Torx® bolt: 16 ft. lbs. (22 Nm) M7 13mm T30 Torx® bolt: 15 ft. lbs. (20 Nm) plus 60 degrees

14.

Install or connect the following: Front cover and top guide rail Timing chain tensioner Valve cover Negative b attery c able


1.


2.

Dis connect the negative battery cab le and position the No. 1 cy linder 30 degrees ATDC.

3.

Remove or disc onnect the following: Valve cover Front timing cover

4.

Matchmark the timing chain (73 ) to the cams haft sp rockets (75 and 76).

5.

Remove or disc onnect the following: Timing chain tensioner (14) Exhaust camshaft sprocket (76) Timing chain from the intake camshaft (75)

6.

Using a wrench (1), rotate the cams hafts (77 and 78 ) so the bas e circle of the cams are resting against the buc ket tappets.

7.

Remove or disc onnect the following: Camshaft bearing c aps Camshafts Bucket tappets To install: Exploded view of the camshaft mounting components and positioning — 2.2L and 2.3L (111) engines

8.

Install the buc ket tappets and oil the cams haft journals and lobes. Position the base circl e of the camshafts so they are resting against the bucket tappets .

9.

Install or connect the following: Camshaft bearing caps. Torque to 44 inch lbs. (5 Nm) plus 90 degrees Timing chain Exhaust camshaft sprocket. Align matchmarks and torque to 15 ft. lbs. (20 Nm) plus 90 degrees Front cover and top guide rail Timing chain tensioner Valve cover Negative b attery c able

3.2L (112) and 4.3L (113) Engines

1.


2.

Dis connect the negative battery cable and remove the cy linder head cover. Rotate the engine clock wise to position the crankshaft 40 degrees ATDC. WARNING The engine must not be rotated backwards.

3.

Remove or disc onnect the following: Generator Timing chain tensioner (2) Camshaft Position Sensor (CMP) (1)

4.

Cable-tie the timing chain to the cams haft sp rocket (5). Lock the cams hafts using cams haft locking (3) tools.

5.

Remove or disc onnect the following: Camshaft gears Camshaft bearing bridge (4) Camshafts Exploded view of the camshaft mounting, showing related components — 3.2L (112) and 4.3L (113) engines

To install: 6.

App ly clean engine oil to the cams haft contact surfaces .

7.

Install or connect the following: Camshafts Camshaft bearing bridge NOTE: The camshafts can be rotated 40 degrees after top dead center of the No. 1 cylinder without the valves touching the pistons.

8.

Position the cams haft so that the groove points towards the contact surface of the cy linder head cover, then attach the camshaft fixing plate. Repeat this step for the other camshaft.

9.

Install or connect the following: Camshaft sprockets. Torque the bolt to 37 ft. lbs. (50 Nm) plus 90–100 degrees Timing chain CMP sensor. Torque the mounting bolt to 70 inch lbs. (8 Nm) Timing chain tensioner with new gasket. Torque to 59 ft. lbs. (80 Nm) Generator Cylinder head cover

10.

Connect the negative battery cab le, start the engine and chec k operation.


1.


2.

Dis connect the negative battery cab le and position the No. 1 cy linder 45 degrees BTDC.

3.

Remove or disc onnect the following: Valve covers Upper front covers (10 and 12)

4.

Matchmark the timing chain to the cams haft sp rockets.

5.

Remove or disc onnect the following: Timing chain tensioner (13) Timing chain top slide rails (1, 1a, 2 and 2a) Timing chain from the camshaft sprockets

6.

Rotate the cams hafts so the bas e circle of the cams are resting against the buc ket tappets.

7.

Remove or disc onnect the following: Camshaft bearing cap bolts Camshaft bearing c aps Camshafts with sprockets Bucket tappets To install: Exploded view of the camshaft mounting and related components — 4.2L and 5.0L (119) engine

8.

Install the buc ket tapp ets and oil the cams haft journals and lobes.

9.

Install or connect the following: Left intake and exhaust camshafts Timing chain on left cylinder head, aligning the matchmarks Left side bearing caps. Torque to 88 inch lbs. (10 Nm) Right intake and exhaust camshafts Timing chain on right cylinder head, aligning the matchmarks Right side bearing caps. Torque to 88 inch lbs. (10 Nm) Timing chain top slide rails Timing chain tensioner Upper front covers Valve covers

Negative b attery c able

6.0L (120) Engines

1.


2.

Dis connect the negative battery cab le and position the No. 1 cy linder 30 degrees ATDC.

3.

Remove or disc onnect the following: Valve covers Upper front covers and top guide rails Timing chain tensioner

4.

Matchmark the timing chain to the cams haft sp rockets.

5.

Remove or disc onnect the following: Exhaust camshaft sprockets Timing chain from the intake camshaft sprockets Bearing caps, except for caps 3, 4, 10, and 11 on the right head, and 17, 18, 24, and 25 on the left head Cylinder and bearing cap identification — 6.0 (120) engines

6.

Loosen the bolts on the remaining bearing cap s 1 turn at a time until the bearing cap s can be removed.

7.

Remove or disc onnect the following: Camshafts Bucket tappets To install:

8.

Install the buc ket tapp ets and oil the cams haft journals and lobes.

9.

Install or connect the following: Camshafts

10.

Bearing cap s 3, 4, 10, and 11 on the right head, and 17, 18 , 24, and 25 on the left head. Torque the bolts in steps of 1 turn to 15 ft. lbs . (21 Nm)

11.

Remaining bearing caps . Torque the bolts to 15 ft. lbs . (21 Nm)

12.

Align the matchmarks and install the timing chain to the intake camshaft sp rockets.

13.

Install or connect the following: Exhaust camshaft sprockets. Torque the bolts to 16 ft. lbs. (22Nm) Timing chain tensioner Upper front covers top guide rails Valve covers Negative b attery c able


All Mercedes-Benz engines use hydraulic valve lifters. There is no provision for valve clearance adjustments.


Exploded view of the oil pan mounting and related components — Inline engines

Lower the front subframe by removing the mounting bolts — except 3.2L (112) and 4.3L (113) engines

Exploded view of the oil pan mounting and related components — Inline engines

Exploded view of the mounting of the upper oil pan and related components — 3.2L (112) and 4.3L (113) engines

Exploded view of the mounting of the lower oil pan and related components — 3.2L (112) and 4.3L (113) engines

2.8L, 3.2L, 3.6L (104) and 2.2L, 2.3L (111) Engines

ALL MODELS EXCEPT E320 (210)

1.


2.

Dis connect the negative battery cable and drain the engine oil.

3.

Remove or disc onnect the following: Fan shroud Engine harness cover Exhaust Exhaust bracket at transmission Oil level sensor connection AutoMatic transmission oil pipes if equipped Drag link Front torsion b ar Engine mounts Rear engine carrier

4.

Using a suitable engine sup port tool, sup port the weight of the engine. Raise the engine to acc ess the oil pan mounting bolts. NOTE: It may be necessary to tap on the oil pan with a rubber mallet to dislodge it from the engine block.

5.

Remove the mounting bolts and the oil pan. Clean all gask et material from the sealing surfaces . To install:

6.

Install or connect the following: Oil pan with a new gasket. Torque the M6 bolts to 88 inch lbs. (9 Nm). Torque the M8 bolts to 15 ft. lbs. (21 Nm). Torque the M10 bolts to 30 ft. lbs. (40 Nm). Rear engine carrier Engine mounts. Torque the bolts to 41 ft. lbs. (55 Nm) Front torsion b ar Drag link AutoMatic transmission oil pipes Oil level sensor connection Exhaust bracket at transmission Exhaust Engine harness cover Fan shroud

7.

Fill the crank case with oil, connect the negative battery cab le, start the engine and chec k for leaks.

E320 (210)

1.


2.

Remove or disc onnect the following: Negative b attery c able Engine oil Fan shroud Power steering lines Front springs Bottom engine mount Steering coupling

3.

Supp ort the front sub frame and remove mounting bolts. Lower the subframe to acc ess the oil pan mounting bolts.

4.

Remove the mounting bolts and the oil pan. Clean all gask et material from the sealing surfaces .

5.


NOTE: It may be necessary to tap on the oil pan with a rubber mallet to dislodge it from the engine block.

To install:

Oil pan with a new gasket. Torque the M6 bolts to 88 inch lbs. (9 Nm). Torque the M8 bolts to 15 ft. lbs. (21 Nm). Torque the M10 bolts to 30 ft. lbs. (40 Nm). Front sub frame. Torque the bolts to 88 ft. lbs. (120 Nm) Steering coupling. Torque the bolt to 18 ft. lbs. (25 Nm)

Engine mount. Torque the bolts to 41 ft. lbs. (55 Nm) Front springs Power steering lines Fan shroud Engine oil Negative b attery c able

3.2L (112) and 4.3L (113) Engines

1.


2.

Remove or disc onnect the following: Negative b attery c able Engine oil Coolant Engine under cover Fan clutch and shroud Engine upper cover Coolant hose at thermostat Coolant hose at water pump NOTE: It may be necessary to tap on the oil pan with a rubber mallet to dislodge it from the engine block.

3.

Remove the mounting bolts and the oil pan. Clean all gask et material from the sealing surfaces . To install:

4.

Install or connect the following: Oil pan with a new gasket. Torque the oil pan bolts to 84 inch lbs. (10 Nm). Coolant hose at water pump Coolant hose at thermostat Fan clutch and shroud Engine upper cover Coolant Engine oil Negative b attery c able


1.


2.

Remove or disc onnect the following: Negative b attery c able Engine oil Coolant Fan clutch and shroud Drive belt and tensioner with bracket Dipstick guide tube at air pump bracket

3.

Remove the air conditioning compressor and position it aside with the lines attached.

4.

Remove or disc onnect the following: Alternator and bracket Dipstick guide tube Engine mounts Front springs and shock ab sorbers Steering coupling

5.

Using a suitab le engine sup port tool, support the weight of the engine.

6.

Supp ort the front sub frame and remove mounting bolts. Lower to acc ess the oil pan mounting bolts.

7.

Remove the mounting bolts and the oil pan. Clean all gask et material from the sealing surfaces .

8.


NOTE: It may be necessary to tap on the oil pan with a rubber mallet to dislodge it from the engine block.

To install:

Oil pan with a new gasket. Torque the M6 bolts to 97 inch lbs. (11 Nm). Torque the M8 bolts to 18 ft. lbs. (25 Nm). Torque the M10 bolts to 30 ft. lbs. (40 Nm). Sub frame. Torque the bolts to 30 ft. lbs. (40 Nm) Steering coupling Front springs and shock ab sorbers Engine mounts. Torque the mounting b olts to 18 ft. lb s. (25 Nm) Dips tick guide tube at oil pump Alternator and bracket. Torque the bracket mounting bolts to 15 ft. lbs. (21 Nm) Air conditioning compressor and bracket. Torque the bracket mounting bolts to 15 ft. lbs. (21 Nm) Dipstick guide tube at air pump bracket Drive belt and tensioner with bracket. Torque the bracket mounting bolts to 15 ft. lbs. (21 Nm) Fan clutch and shroud Engine oil Negative b attery c able

6.0L (120) Engine

1.


2.


Negative Negat ive b att attery ery c able Engine oil Engine Eng ine assemb ly Alternato Altern ator r Oil pressure sensor wire connection Dipstick guide tube Vibration damper Secondary air injection line Oil pan end cover NOTE: It may be necessary to tap on the oil pan with a rubber mallet to dislodge it from the engine block. 3.

Remove the the mounting mounting bolts and the oil pan. Clean all gask et material material from from the sealing surfaces .

4.

Install or connect the fo following: llowing:

To install:

Oil pan with a new gasket. Torque the M6 bolts to 88 inch lbs. (9 Nm). Torque the M8 bolts to 15 ft. lbs. (21 Nm). Torque the M10 bolts to 30 ft. lbs. (40 Nm). Oil pan end cover Secondary air injection line Vibration damper Dipstick guide tube Alternato Altern ator r Engine Eng ine assemb ly Engine oil Negative Negat ive b att attery ery c able


2.8L, 3.2L, 3.6L (104), 2.2L, 2.3L (111), 3.2L (112) and 4.3L (113) Engines

Exploded view of the oil pump mounting and related component — except 3.2L (112) and 4.3L (113) engines

1.


2.

Remove or disc onnect the fo following: llowing: Oil pan Oil pump drive gear Oil pump mounting bolts Oil pump To install: NOTE: Be sure to replace any O-rings or seals between the oil pump and engine block.

3.

Install the the oil pump and tighten tighten the the mounting mounting bolts as follow follows: s: M6 bolts: 88 inch lbs. (9 Nm) M8 bolts: 15 ft. lbs. (21 Nm)

4.

Install or connect the fo following: llowing: Oil pump drive gear. Torque the bolt to 24 ft. lbs. (32 Nm) Oil pan Engine oil Exploded view of the oil pump mounting and related component — 3.2L (112) and 4.3L (113) engines


1.


2.

Remove or disc onnect the fo following: llowing: Ground straps AutoMatic Auto Matic transmission transmission oil line bracket Oil level control hose Oil pan Oil pump drive gear Oil pump

NOTE: Be sure to replace any O-rings or seals between the oil pump and engine block. To install: 3.

Install or connect the fo following: llowing: Oil pump. Torque the mounting bolts to 15 ft. lbs. (21 Nm) Oil pump drive gear. Torque the mounting bolt to 24 ft. lbs. (28 Nm) Oil pan Oil level control hose AutoMatic Auto Matic transmission transmission oil line bracket Ground straps Engine oil

6.0L (120) Engine

1.


2.

Remove or disc onnect the fo following: llowing: Negative Negat ive b att attery ery c able Engine oil Oil pan Oil pump drive gear Oil pump mounting bolts Oil pump NOTE: Be sure to replace any O-rings or seals between the oil pump and engine block. To install:

3.

Install or connect the fo following: llowing: Oil pump. Torque the M6 bolts to 88 inch lbs. (9 Nm) and the M8 bolts to 15 ft. lbs. (21 Nm) Oil pump drive gear with curved face towards pump. Torque the mounting bolt to 24 ft. lbs. (28 Nm) Oil pan Engine oil


All Models NOTE: All engines use a 1 piece radial seal.

1.


2.

Remove or disc onnect the fo following: llowing: Negative Negat ive b att attery ery c able Transmission Tr ansmission assemb ly Flywheel or flexplate Rear main seal using a suitable prying tool To install:

3.

Coat the inner lip of the the seal with engine oil. Using a seal driver, install the seal into the retainer. retainer.

4.

Install or connect the fo following: llowing: Flywheel or flexplate Transmission Tr ansmission assemb ly Negative Negat ive b att attery ery c able


2.8L, 3.2L, 3.6L (104) Engines

1.


2.

Remove or disc onnect the following: Coolant Negative b attery c able Alternator and bracket Engine cover, air cleaner and intake scoop Fan clutch, belt and pulleys Wiring and hoses

3.

Remove the upp er timing cover and mark the timing chain and sp rockets.

4.

Remove or disc onnect the following: Timing chain and tensioner Access ories as needed, referring to the illustration for the specific model Crankshaft Position Sensor (CKP) Crankshaft pulley

5.

Remove the timing cover. Make sure to clean all gasket material from the sealing surfaces .

6.


To install:

Timing cover with new gasket. Torque the M6 bolts to 84 inch lbs. (10 Nm). Torque the M8 bolts to 15 ft. lbs. (21 Nm). Crankshaft pulley CKP sensor Access ories Timing chain and tensioner Wiring and hoses Fan clutch, belt and pulleys Alternator and bracket Engine cover, air cleaner and intake scoop Negative b attery c able Coolant

2.2L, 2.3L (111) Engines

1.


2.

Remove or disc onnect the following: Coolant Negative b attery c able Left charge air pip e Oil filter Oil pan Fan clutch and shroud Access ory drive belt Air conditioning compressor. Position it aside with the lines attached Alternator and bracket Access ory drive belt tensioner Cylinder head front cover Water pump Power steering pump pulley

3.

Position crank shaft to 20–3 0 degrees ATDC for cylinder No. 1.

4.

Lock the camshafts with lock ing pins and matchmark the timing chain to the sp rockets.

5.

Remove or disc onnect the following: Timing chain tensioner Camshaft sprockets Intake camshaft with adjuster Vibration damper and pulley

6.

Remove the timing cover. Make sure to clean all gasket material from the sealing surfaces .

7.


To install:

Timing cover with new gasket. Torque the mounting bolts to 18 ft. lbs. (25 Nm). Vibration damper and pulley Intake camshaft with adjuster Camshaft sprockets. Torque the mounting bolts to 15 ft. lbs. (20 Nm), plus an additional 90 degrees Timing chain tensioner 8.


9.


To install: 6.

Install or connect the following: Timing cover with new gasket. Torque the mounting bolts to 15 ft. lbs. (21 Nm). Dipstick guide tube Oil pan Air conditioning compressor and bracket. Torque the mounting bolts to 15 ft. lbs. (21 Nm) Water pump. Torque the mounting bolts to 15 ft. lbs. (21 Nm) Front cover oil seal Vibration damper hub Vibration damper and pulley Air pump and brack et Water pump p ulley Coolant hoses at radiator and thermostat housing Camshaft adjusters Timing chain tensioner and guides

7.


8.

Install or connect the following: Alternator and bracket. Torque the mounting bolts to 15 ft. lbs. (21 Nm) Upper timing covers. Torque the mounting bolts to 15 ft. lbs. (21 Nm) Engine cover Fan clutch and shroud Negative b attery c able Coolant

6.0L (120) Engine

1.


2.

Remove or disc onnect the following: Coolant Negative b attery c able Fan clutch and shroud Air cleaner MAF sensor Water pump Air pump and brack et if equipped Alternator and bracket

3.

Position crank shaft to 30 degrees ATDC for cy linder No. 1.

4.

Lock the camshafts with lock ing pins and matchmark the timing chain to the sp rockets.

5.

Remove or disc onnect the following: Power steering pump and bracket. Position it aside with the lines attached TDC sensors Secondary air pump air cleaner and bracket Timing chain tensioner Secondary air injection line if equipped Oil pan bottom cover Remove the timing cover. Make sure to clean all gasket material from the sealing surfaces. Replace the timing case cover O-rings. To install:

6.

Install or connect the following: Timing cover with new gasket. Torque the M6 bolts to 88 inch lbs. (9 Nm), the M8 bolts to 15 ft. lbs. (21 Nm), and the M8 bolts to 18 ft. lbs. (25 Nm). Oil pan bottom cover Secondary air injection line Timing chain tensioner Secondary air pump air cleaner and bracket TDC sensors Power steering pump and b racket

7.


8.

Install or connect the following: Alternator and bracket Air pump and brack et if equipped Water pump MAF sensor Air cleaner Fan clutch and shroud Negative b attery c able Coolant Exploded view of the lower timing cover mounting and related components — 2.8L and 3.2L (104) engine in the SL Class (129)

Exploded view of the lower timing cover mounting and related components — 2.8L and 3.2L (104) engine in the S Class (140)

Exploded view of the lower timing cover mounting and related components — 2.8L, 3.2L and 3.6L (104) engine in the C Class (202) and E Class (210) models

Exploded view of the lower timing cover mounting and related components — 2.2L and 2.3L (111) engines in the E Class (210) models

Exploded view of the lower timing cover mounting and related components — 3.2L (112) and 4.3L (113) engines in the C Class (202) and E Class (210) models

Exploded view of the lower timing cover mounting and related

components — 4.2L and 5.0L (119) engines

Exploded view of the lower timing cover mounting and related components — 6.0L (120) engines


All Models NOTE: An endless timing chain is used on production engines, but a split chain with a connecting link is used for service. The endless chain can be separated with a "chain breaker". Only 1 master link (connecting link) should b e used on a chain.

1.


2.

Remove or disc onnect the following: Negative b attery c able Spark plugs Valve cover(s) Engine timing covers

3.

Clamp the chain to the camshaft gear and cover the opening of the timing chain case.

4.

Separate the chain with a chain break er. To install: Replacing the timing chain — 104 engine shown

5.

Attach a new timing chain (5) to the old chain (4) with a master link (6), center pl ate (7) and end plate (8). Using a socket wrench on the cranks haft, slowly rotate the engine in the direction of normal rotation. Simultaneously, pull the old chain through until the master link is uppermost on the camshaft sprocket (9). Be sure to keep tension on the chain throughout this p rocedure.

6.

Dis connect the old timing chain and connect the ends of the new chain with the master link. Insert the new connecting link from the rear so the lockwashers c an be seen from the front.

7.

Rotate the engine until the timing marks align. Check the valv e timing.

8.

Install or connect the following: Engine timing covers Valve covers Spark plugs Negative b attery c able

9.

Start the engine and check operation.


Cylinder identification and piston identifications must agree (see arrows)

Install pistons so the code (5) next to the piston pin and group number (6) are pointing in the direction of travel, and the identification (9) on the connecting rod is facing to the outside of the engine.

Ring positioning


NOTE: In all cases, Mercedes-Benz engines and transmissions are removed as a unit.

1.


2.

Remove or disc onnect the fo following: llowing: Coolant Engine oil Transmission fluid Hood Battery Heater hoses and oil cooler lines Fan s hroud and radiator Air cleaner Fuel, vacuum and oil hoses Fan clutch and fan Acceleratorr linkage Accelerato Ground straps and electrical connections Gearshift linkage Exhaust pipes

3.

Loosen Loo sen the steering relay arm and move it aside, along with the center steering rod and hydraulic steering damper.

4.

Remove or disc onnect the fo following: llowing: Hydraulic engine shock shock absorber Transmission oil line connectors Exhaust pipe bracket

5.

Supp ort the bell housing or or place a cab le sling under the oil pan to sup port the the engine. On turbocharged models, disc onnect the the exhaust pip es at the turbocharger. Mark the position of the rear engine support and unbolt the 2 outer bolts. Remove the top bolt at the transmission and pull the support out.

6.

Remove or disc onnect the fo following: llowing: Speedometer cable Front driveshaft U-joint. Push the driveshaft back and wire it aside Engine mounts

7.

Unbolt the the power steering fluid reservoir and move move it aside. Using a chain hoist hoist and cable, l ift the the engine and transmiss ion upward and outw outward. ard. To install:

8.

Install or connect the fo following: llowing: Engine Eng ine and transmission ass embly Engine mounts. Torque the bolts to 30 ft. lbs. (40 Nm) Front driveshaft U-joint Speedometer cable Exhaust pipes and bracket Rear engine support Exhaust pipe bracket Exhaust pipes at the turbocharger if equipped. Torque the bolts to 25 ft. lbs. (34 Nm) Transmission oil line connectors Hydraulic engine shock shock absorber

9. 10.

Torque the steering relay arm to to 15 ft. ft. lbs. (20 Nm). Connect Connect the steering damper to the steering linkage. Install or connect the fo following: llowing: Gearshift linkage and exhaust pipes. Torque the manifold bolts to 25 ft. lbs. (34 Nm). Ground straps and electrical connections Acceleratorr linkage Accelerato Fan clutch and fan Fuel, vacuum and oil hoses Air cleaner Radiatorr and fan shroud Radiato Heater hoses and oil cooler lines Battery Coolant Engine oil Transmission fluid


1.


2.

Remove or disc onnect the fo following: llowing: Negative Negat ive b att attery ery c able Fan clutch, fan and shroud Water Wat er pump p ulley Hex nuts and magnet body Water pump housing NOTE: The magnet carrier is glued to the water pump housing and should not be pulled off. To install: Exploded view of the water pump housing assembly — Diesel engines

3.

Install or connect the fo following: llowing: Water pump housing and gasket. Torque combination screws to 90 inch lbs. (10 Nm) Magnet body and hex nuts Water pump pulley. Torque the screws to 90 inch lbs. (10 Nm) Fan clutch, fan and shroud Coolant Negative Negat ive b att attery ery c able


The glow plugs are located on the left side of the cylinder head.

1.


2.

Remove or disc onnect the fo following: llowing: Negative Negat ive b att attery ery c able Glow plug electrical connectors Glow plugs To install:

3.

App ly anti-seize anti-seize compound to the glow plug threads. threads.

4.

Install or connect the fo following: llowing: Glow plugs. Torque to 15 ft. lbs. (20 Nm) Glow plug electrical connector. Torque the retaining nut to 35 inch lbs. (4 Nm) Negative Negat ive b att attery ery c able


NOTE: Use care to ensure that the valve timing is not disturbed.

1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Hoses and wires Camshaft cover Throttle link age Camshaft sprocket nuts

4.

Mark the chain, sp rocket and cam for ease of assemb ly. Remove the sprocket and chain and wire it aside. Unbolt the manifolds and exhaust header pip e and set them aside.

5.


NOTE: Be sure the chain is securely wired so it will not slide into the engine.

Cylinder head bolts in the reverse order of the illustrated sequence. Cylinder head 6.

Clean all gasket material from the sealing surfac es. Be sure the cylinder head locating dowels are positioned in the engine block . WARNING All Diesel engines utilize cylinder head stretch bolts. These bolts undergo a permanent stretch each time they are tightened. When a maximum length is reached, they must be replaced with new bolts. Before tightening the head bolts on these engines, refer to the illustration for the specific length of the bolts. Be sure to replace bolts that are beyond maximum length — Diesel engines

To install: 7.

Install the cy linder head and gasket. Torque the cy linder head bolts in sequenc e as follows: 11 ft. lbs. (15 Nm) 20 ft. lbs. (35 Nm) + 90 degrees wait 10 minutes + additional 90 degrees

8.

Install or connect the following: Manifolds and exhaust header pipe. Torque the pipe fasteners to 24 ft. lbs. (34 Nm) Sprocket and chain Camshaft sprocket nuts Trowel linkage Camshaft cover Hoses and wires Coolant Negative b attery c able


The Diesel engine does not use rocker arms. The camshafts act directly on the hydraulic valve tappets.


1.


2.

Remove or disc onnect the following: Negative b attery c able Air filter Temperature switch electrical cable Air filter to compressor housing hose clamp Vacuum line and crankcase b reather pipe Air intake duct Turbocharger oil line Air filter mounting bracket Turbocharger exhaust flange Transmission pip e brack et. Push the pipe rearward Intermediate flange mounting bracket Turbocharger Intermediate flange and turbocharger oil return line To install:

3.

Install or connect the following: Oil return line and intermediate flange Flange gasket between the turbocharger and exhaust manifold with the reinforcing bead toward the exhaust manifold. Use only heat-proof nuts and bolts. Intermediate flange mounting bracket Transmission pipe bracket Turbocharger exhaust flange Air filter mounting bracket Turbocharger oil line Air intake duct Vacuum line and crankcase b reather pipe Air filter-to-compressor housing hose clamp Temperature switch electrical cable Air filter 1 ⁄ pint of engine oil through the oil supply into a new turbocharger 4 Negative b attery c able


1.


2.

Remove or disc onnect the following: Negative b attery c able Engine ventilation tubes Electrical wiring, c ables and hoses Manifold retaining bolts and manifold. To install:

3.

Clean the gask et mating surfaces and install a new gask et.

4.

Install or connect the following: Manifold and bolts. Torque bolts to 18 ft. lbs. (25 Nm), working from the middle outward Electrical wiring, c ables and hoses Engine ventilation tubes Negative b attery c able


1.


2.

Remove or disc onnect the following: Negative b attery c able Exhaust pipe Manifold retaining bolts and manifold To install:

3.

Clean the gask et mating surfaces and install a new gask et.

4.

Install or connect the following: Manifold and bolts. Torque bolts to 18 ft. lbs. (25 Nm), working from the middle outward Exhaust pipe Negative b attery c able


1.


2.

Remove or disc onnect the following: Negative b attery c able Cylinder head cover

3.

Set cranks haft to TDC of No. 1 cyl inder. Remove the timing chain tensioner and mark the camshaft timing gears and timing chain in relation to each other.

4.

Remove or disc onnect the following: Camshaft timing gears Pressure oil pump if equipped with level control. Place aside leaving the lines connected. Camshaft bearing c aps Camshafts Valve tappets using a lifter tool. To install:

5.

Insert the circ lip for axial locating into the cy linder head. Lubric ate and install the valve tappets and camshafts.

6.

Install or connect the following: Camshaft bearing caps opposite of the loosening sequence. Torque bearing caps to 18 ft. lbs. (25 Nm) Camshaft timing gears. Torque the fastening screw to 48 ft. lbs. (65 Nm) Timing chain tensioner Pressure oil pump Cylinder head cover Negative b attery c able


Diesel engines use hydraulic valve lifters. There is no provision for valve clearance adjustments.


1.


2.

Remove or disc onnect the following: Negative b attery c able Starter wires and bracket Starter mounting b olts Starter ass embly To install:

3.

Install or connect the following: Starter assembly. Torque the mounting bolts to 31 ft. lbs. (42 Nm) Starter wires and bracket Negatives battery c able Start the vehicle and check for proper operation.


1.


2.

Dis connect the negative battery cable and drain the engine oil.

3.

Using a suitab le engine sup port tool, sup port the weight of the engine.

4.

Supp ort the front sub frame and remove the mounting bolts. Lower to acc ess the oil pan mounting bolts.

5.

Remove the mounting bolts and the oil pan. Clean all gask et material from the sealing surfaces . To install: Exploded view of the oil pan mounting and related removal and installation components — Diesel engines

6.

Install or connect the following: Oil p an with new gasket Oil p an mounting bolts in crissc ross pattern Front subframe Engine oil Negative b attery c able


1.


2.

Remove or disc onnect the following: Negative b attery c able Oil pan Oil pump s procket Oil pump To install: Exploded view of the oil pump mounting — Diesel engine

3.

Install or connect the following: Oil pump. Torque to 18 ft. lbs. (25 Nm). Sprocket and chain NOTE: Mount the sprocket so that the rise points toward the oil pump and so that the trochoid shape corresponds with that on the oil pump shaft.

4.

Oil pan

5.

Engine oil


NOTE: All engines use a 1-piece radial seal.

1.


2.

Remove or disc onnect the following: Negative b attery c able Transmission assemb ly Flywheel or flexplate Rear main seal using a suitable prying tool To install:

3.

Coat the inner lip of the seal with engine oil.

4.

Install or connect the following: Seal into the retainer Flywheel or flexplate Transmission assemb ly Negative b attery c able


1.


2.

Remove or disc onnect the following: Coolant Negative b attery c able Engine undercover Serpentine b elt Fan s hroud and radiator Fan clutch and fan Crankshaft pulley Serpentine belt tensioner Vacuum pump Power steering pump Self-leveling susp ension hydraulic p ump Alternator

3.

Cover the air conditioning condenser using a piece of sheet metal, ply wood or plastic .

4.

Remove or disc onnect the following: Cylinder head cover and charge air pip e Oil dipstick tube TDC sensor, marking its position

5.

Supp ort the engine and remove the engine mounts. Raise the engine to gain acces s.

6.

Remove the timing cover bolts and carefully remove the cover from the engine. Be careful not to damage the oil pan and cylinder head gaskets.

7.


To install:

Timing cover. Torque the bolts to 18 ft. lbs. (25 Nm) Engine mounts TDC sensor Oil dipstick tube Cylinder head cover and charge air pip e 8.

Remove the air conditioning condenser guard

9.

Install or connect the following: Alternator Self-leveling susp ension hydraulic p ump Power steering pump Vacuum pump Serpentine belt tensioner Crankshaft pulley Fan clutch and fan Radiator and fan shroud Serpentine b elt Engine undercover Negative b attery c able Coolant


1.


2.

Remove or disc onnect the following: Negative b attery c able Cylinder head cover Injection nozzles Chain tensioner Fan and shroud Engine timing cover

3.

Clamp the chain to the camshaft gear and cover the opening of the timing chain case.

4.

Separate the chain with a chain break er.

5.

Attach a new timing chain to the old chain with a master link. Using a socket wrench on the cranks haft, slowly rotate the engine in the direction of normal rotation. Simultaneously, pull the old chain through until the master link is uppermost on the camshaft sprocket. Be sure to keep tension on the chain throughout this procedure.

6.

Dis connect the old timing chain and connect the ends of the new chain with the master link. Insert the new connecting link from the rear so the lockwashers c an be seen from the front.

7.

Install the timing chain tensioner. Rotate the engine until the timing marks ali gn. Check the valve timing.

8.


To install:

NOTE: Use only a rivet-type connecting link. Do not use connecting link that uses a retaining spring.

Engine timing cover. Torque the bolts to 18 ft. lbs. (25 Nm) Cylinder head cover. Torque to 90 inch lbs. (10 Nm) Fan and fan shroud Injection nozzles Negative b attery c able


Cylinder identification and piston identifications must agree (see arrows)

Install pistons so the code (5) next to the piston pin and group number (6) are pointing in the direction of travel, and the identification (9) on the connecting rod is facing to the outside of the engine.

Ring positioning


Although different maintenance intervals are given by each manufacturer, it is a good rule of thumb to inspect the drive belts every 15,00 0 miles (24,0 00 km) or 12 months (whichever occurs first). Determine the belt tension at a point half-way between the pulleys by pressing on the belt with moderate thumb pressure. The belt should deflect about 1 ⁄ 4 – 1 ⁄ 2 in. (6 –13mm) at this point. Note that "deflection" is not play, but the ability of the belt, under actual tension, to stretch slightly and give. Inspect the belts for the following signs of damage or wear: glazing, cracking, fraying, crumbling or missing chunks. A glazed belt will be perfectly smooth from slippage, while a good belt will have a slight texture of fabric visible. Cracks will usually start at the inner edge of the belt and run outward. A belt that is fraying will have the fabric backing de-laminating itself from the belt. A belt that is crumbling or missing chunks will have voids in the cross-section of the belt, some times the section missing chunks will be in the pulley groove and not easily seen. All worn or damaged drive belts should be replaced immediately. It is best to replace all drive belts at one time, as a preventive maintenance measure. Although, it is generally easier on the component to have the belt too loose than too tight, a very loose belt may p lace a high impact load on a bearing due to the whipping or snapping action of the belt. A belt that is slightly loose may slip, especially when component loads are high. This slippage may be hard to identify. For example, the generator belt may run okay during the day, then slip at night when the headlights are turned ON. Slipping belts wear quickly not only due to the direct effect of slippage but also because of the heat the slippage generates. Extreme slippage may even cause a belt to burn. A very smooth, glazed appearance on the belt's sides, as opposed to the obvious pattern of a fabric cover, indicates that the belt has been slipping. An example of a healthy drive belt

Deep cracks in this belt will cause flex, building up heat that will eventually lead to belt failure

The cover of this belt is worn, exposing the critical reinforcing cords to excess ive wear

Installing too wide a belt can result in serious belt wear and/or breakage


CAUTION On vehicles with an electric cooling fan, disable the power to the fan by disengaging the fan motor wiring connector or removing the negative battery cable before replacing or adjusting the drive belts. Otherwise, the fan may engage even though the ignition is OFF. Belt tension can be checked by pressing on the belt at the center point of its longest straight span. The belt should give approximately 1 ⁄ 4 – 1 ⁄ 2 in. (6–13mm). If the belt is loose it will slip, whereas if the belt is too tight it will damage the bearings in the driven unit. For the purposes of V-belt tensioning, there are generally three types of mounting for the various components driven by the drive belt. The first method, referred to as pivoting type without adjuster, is designed so that the component is secured by at least 2 bolts. One of the bolts is a pivoting bolt and the other is the lockbolt. When both bolts are loosened so that the component may move, the component pivots on the pivoting bolt. The lockbolt passes through the component and a slotted bracket, so that when the lockbolt's nut is tightened the component is held in that position. There are no automatic adjusting mechanisms used with this type of mounting. The second method of component mounting, referred to as pivoting type with adjuster, is almost identical except for the addition of an adjuster of some sort. Usually, the adjuster is composed of a bracket attached to the component and a threaded adjusting bolt. After loosening the pivoting and lockbolts, the adjusting bolt can be tightened or loosened to increase or decrease the drive belt's tension. With this type of mounting, you do not have to hold the component in a tensioned position and tighten the pivoting and lockbolts; the adjusting bolt does the job for you. Some versions of this method of mounting use an adjuster which is built into one of the components mounting braces. The brace attaches the component to the engine and incorporates a threaded adjuster in its mid-span, so that when the threaded adjuster is turned the brace shortens or lengthens. This in turn increases or decreases the amount of tension on the component. The third type of mounting, referred to as stationary type, is designed so that the component is mounted on its brackets. There are no pivoting or lockbolts, and the component is not designed to be moved. Rather, this type of mounting uses an extra tensioner idler pulley assembly. The drive belt is tensioned by adjusting the position of the idler pulley, usually accomplished by turning the adjuster bolt on the idler mechanism. A typic al pivoting accessory with an adjusting bolt

An accessory that is fixed will have an adjustable pulley — notice the square slot to aid the adjustment

Pivoting Type

WITHOUT ADJUSTER

1.


2.

Loosen the component's lock bolt and pivoting bolt only enough for the component to move.

3.

Using a pry tool, move the component either closer to, or farther away from the engine, to provide the correct tension on the belt. WARNING If using a metal prytool, always wrap the end with a rag or towel to prevent accidentally damaging the component from undue stress.

4.

Onc e the proper amount of tension is ap pli ed to the drive belt, hold the prytool with one hand while tightening the lock bolt securely with the other hand.

5.

Release the pres sure from the pry tool and tighten the pivoting bolt securely.

6.

Double check the drive belt's tension, in cas e the component moved slightly while tightening the bolts.

7.


WITH ADJUSTER

This type of drive belt is tensioned by a tensioner, which makes precise tension adjustment easy.

1.


2.

Loosen the component's piv ot and lockb olts.

3.

Inspec t the tensioner assemb ly on the component; the tensioner adjusting bolt may use a locknut or screw to prevent it from loosening over time. On the type of adjuster with a threaded mounting brace, there may be two jam nuts used on either side of the threaded coupling. If such locking fasteners are found, loosen them.

4.

Turn the tensioner adjusting bolt or threaded coupling to increase or decreas e the amount of tension on the drive bel t, as necess ary.

5.

When the belt tension is correct, tighten the lock bolt and the piv ot bolt.

6.

If equipp ed, tighten the tension adjusting bolt lock nut or screw to prevent the adjuster from slowly loosening over time. If equipp ed, tighten the two jam nuts.

7.


Stationary Type

IDLER PULLEY WITH ADJUSTING BOLT

1.

Loosen the idler bracket pivot bolt and locking bolts.

2.

Adjust the belt tension by inserting the proper size ratchet in the square slot of the idler bracket and rotating the bracket until tension is appl ied.

3.

While holding the tension on the belt with the ratchet, tighten the locking bolts, then the piv ot bolt.

IDLER PULLEY WITHOUT ADJUSTING BOLT

1.

Loosen the mounting/piv ot bolt behind the idler pulley.

2.

Swivel the idler pulley with a pair of pli ers or a wrench on the bearing mounting until the proper tension is achiev ed.

3.

While holding the idler pulley, at the proper tension, tighten the mounting/pivot bolt.


If a belt must be replaced, the driven unit or idler pulley must be loosened and moved to its extreme loosest position, generally by moving it toward the center of the motor. After removing the old belt, check the pulleys for dirt or built-up material which could affect belt contact. Carefully install the new belt, remembering that it is new and unused; it may appear to be just a little too small to fit over the pulley flanges. Fit the belt over the largest pulley (usually the crankshaft pulley at the bottom center of the motor) first, then work on the smaller one(s). Gentle pressure in the direction of rotation is helpful. Some belts run around a third, or idler pulley, which acts as an additional pivot in the belt's path. It may be possible to loosen the idler pulley as well as the main component, making your job much easier. Depending on which belt(s) you are changing, it may be necessary to loosen or remove other interfering belts to get at the one(s) you want. When buying replacement belts, remember that the fit is critical according to the length of the belt ("diameter"), the width of the belt, the depth of the belt and the angle or profile of the V shape or the ribs. The belt shape should match the shape of the pulley exactly; belts that are not an exact match can cause noise, slippage and premature failure. After the new belt is installed, draw tension on it by moving the driven unit or idler pulley away from the motor and tighten its mounting bolts. This is s ometimes a three or four-handed job; you may find an assistant helpful. Be sure that all the bolts you loosened get retightened and that any other loosened belts also have the correct tension. A new belt can be expected to stretch a bit after installation so be prepared to readjust your new belt, if needed, within the first two hundred miles of use.

Pivoting Type CAUTION On vehicles with an electric cooling fan, disable the power to the fan by disengaging the fan motor wiring connector or removing the negative battery cable before replacing or adjusting the drive belts. Otherwise, the fan may engage even though the ignition is OFF.

WITHOUT ADJUSTER

1.


2.

Loosen the acc ess ory's sl otted adjusting bracket bolt. If the hinge bolt is exces siv ely tight, it too will have to be loosened.

3.

Push the component toward the engine to provide enough slack in the belt so that it will sli de over one of the access ory drive pulley s. Remove the drive belt from the acc ess ory drive pulleys and from the vehicle.

4.

Position the new drive belt over the component pull eys . Be sure that it is routed correctly.

5.

Adjust the tension of the belt, as describ ed earlier in this section.

6.


To install:

WITH ADJUSTER

1.


2.

Loosen the component's piv ot and lockb olts.

3.

Inspec t the tensioner assemb ly on the component; the tensioner adjusting bolt may use a locknut or screw to prevent it from loosening over time. On the type of adjuster with a threaded mounting brace, there may be two jam nuts used on either side of the threaded coupling. If such locking fasteners are found, loosen them.

4.

Turn the tensioner adjusting bolt or threaded coupling to relieve all tension from the drive bel t.

5.

Slip the belt off of the access ory pulley, then remove it from the other pulleys . Remove the belt from the vehic le.

6.

Route the new belt on the component pulley s. Make certain that it is routed correctly; incorrect routing could caus e components to sp in back ward, possib ly damaging it.

7.

Onc e the belt is correctly positioned on all of the pulley s, adjust the tension as descri bed earlier in this section.

8.


To install:

Stationary Type

IDLER PULLEY WITH ADJUSTING BOLT

1.


2.

Loosen the idler bracket pivot bolt and locking bolts.

3.

Move the idler pulley until the most amount of slac k is gained.

4.

Remove the drive belt from the acc ess ory pull ey, then from the other applic able pull eys.

5.

Position the new belt over the crankshaft pulley, the idler pulley and the acces sory pulley. Make certain that it is correctly routed, otherwise it could cause the acc ess ory to be rotated backwards. This could cause damage to the accessory.

To install:

6.

Adjust the belt tension, as descri bed earlier in this section.

7.

While holding the tension on the belt with the ratchet, tighten the locking bolts, then the piv ot bolt.

8.


IDLER PULLEY WITHOUT ADJUSTING BOLT

1.


2.

Loosen the mounting/piv ot bolt behind the idler pulley.

3.

Remove the drive belt from the acc ess ory pull ey, then from the other app licab le pulleys . To install:

4.

Position the new belt over the crankshaft pulley, the idler pulley and the acces sory pulley. Make certain that it is correctly routed, otherwise it could cause the acc ess ory to be rotated backwards. This could cause damage to the accessory.

5.

Swivel the idler pulley with a pair of pli ers or a wrench on the bearing mounting until the proper tension is achiev ed.

6.

While holding the idler pulley, at the proper tension, tighten the mounting/pivot bolt.

7.



Although many manufacturers recommend that the drive belt(s) be inspected every 30 ,00 0 miles (48 ,00 0 km) or more, it is really a good idea to check them at least once a year, or at every major fluid change. Whichever interval you choose, the belts should be checked for wear or damage. Obviously, a damaged drive belt can cause problems should it give way while the vehicle is in operation. But, improper length belts (too short or long), as well as excessively worn belts, can also cause problems. Loose accessory drive belts can lead to poor engine cooling and diminished output from the alternator, air conditioning compressor or power steering pump. A belt that is too tight places a severe strain on the driven unit and can wear out bearings quickly. Serpentine drive belts should be inspected for rib chunking (pieces of the ribs breaking off), severe glazing, frayed cords or other visible damage. Any belt which is missing sections of 2 or more adjacent ribs which are 1 ⁄ 2 in. (13mm) or longer must be replaced. You might want to note that serpentine belts do tend to form small cracks across the backing. If the only wear you find is in the form of one or more cracks are across the backing and NOT parallel to the ribs, the belt is still good and does not need to be replaced. Typical wear patterns for a serpentine drive belt


Periodic drive belt tensioning is not necessary, because an automatic spring-loaded tensioner is used with these belts to maintain proper adjustment at all times. The tensioner is also useful as a wear indicator. When the belt is properly installed, the arrow on the tensioner housing must point within the acceptable range lines on the tensioner's face. If the arrow falls outside the range, either an improper belt has been installed or the belt is worn beyond its useful life span. In either case, a new belt must be installed immediately to assure proper engine operation and to prevent possible accessory damage. Typical drive belt automatic tensioner wear indicator


Because serpentine belts use a spring loaded tensioner for adjustment, belt replacement tends to be somewhat easier than it used to be on engines where accessories were pivoted and bolted in place for tension adjustment. Basically, all belt replacement involves is to pivot the tensioner to loosen the belt, then slide the belt off of the pulleys. The two most important points are to pay CLOSE attention to the proper belt routing (since serpentine belts tend to be "snaked" all different ways through the pulleys) and to be sure the V-ribs are properly seated in all the pulleys. Although belt routing diagrams have been included in this section, the first places you should check for proper belt routing are the labels in y our engine compartment. These should include a belt routing diagram which may reflect changes made during a production run.

1.

Dis connect the negative battery cab le for safety. This will help ass ure that no one mistak enly crank s the engine over with your hands between the pulleys , and that the cooling fan cannot activate while servicing the belt(s). NOTE: Take a good look at the installed belt and make a note of the routing. Before removing the belt, be sure the routing matches that of the belt routing label or one of the diagrams in this book. If for some reason a diagram does not match (you may not have the original engine or it may have been modified), carefully note the changes on a piece of paper.

2.

For tensioners equipp ed with a 1 ⁄ 2 in. (13mm) square hole, insert the drive end of a large breaker bar into the hole. Use the breaker bar to pivot the tensioner away from the drive belt. For tensioners not equipped with this hole, use the proper-sized socket and breaker bar (or a large handled wrench) on the tensioner idler pulley center bolt to pivot the tensioner away from the belt. This will loosen the belt sufficiently that it can be pulled off of one or more of the pulleys. It is usually easiest to carefully pull the belt out from underneath the tensioner pulley itself.

3.

Onc e the belt is off one of the pulleys , gently piv ot the tensioner back i nto position. DO NOT allow the tensioner to snap b ack , as this could damage the tensioner's internal parts.

4.

Now finish removing the belt from the other pulleys and remove it from the engine. To install:

5.

While referring to the proper routing diagram (which you identified earlier), begin to route the belt over the pull eys , leaving whic hever pull ey you first released it from for last.

6.

Onc e the belt is mostly in pl ace, carefully piv ot the tensioner and position the belt over the final pulley. As you begin to allow the tensioner bac k into contact with the belt, run your hand around the pulleys and be sure the belt is properly seated in the ribs. If not, release the tension and seat the belt.

7.

Onc e the belt is installed, take another look at all the pull eys to double check your installation.

8.

Connect the negative battery cable, then start and run the engine to check b elt operation.

9.

Onc e the engine has reached normal operating temperature, turn the ignition OFF and check that the belt tensioner arrow is within the proper adjustment range. Often the underhood label will display the serpentine drive belt routing

Relieve the belt tension by pivoting the automatic tensioner away from the belt, then remove the belt

Verifying serpentine belt alignment in the pulley

Fig. 1 Serpentine drive belt routing — Mercedes-Benz 2.8L, 3.2L, 4.2L, 4.3L, 5.0L and 6.0L engines

Fig. 2 Serpentine drive belt routing — Mercedes-Benz 2.2L, 2.3L (non-supercharged) and 3.0L Diesel engines

Fig. 3 Serpentine drive belt routing — Mercedes-Benz 2.3L supercharged engines


Behr Style

1.


2.

Drain the cooling sy stem into a clean container for reuse.

3.

Remove or disc onnect the following: Hoses from the heater supply and return pipes. Using compressed air, blow the residual coolant from the heater core Instrument panel Upper heater box cover-to-heater box screws, the 6 clips and the cover Heater supp ly p ipe-to-chassis clamp in the engine compartment Heater supply and return pipes-to-heater core screws from the top of the heater box and swing the pipes away from the heater box Pull the heater core from the top of the heater box

4.

Clean any spill ed coolant from inside the heater box. View of the heater box and related components — BEHR style — 300D Turbo, 300E, 300CE, 300TE, 300E, 4Matic, 300 TE 4Matic

To install: 5.

Install or connect the following: Heater core into the heater box Heater supply and return pipes to the heater box using 3 new sealing rings Heater supp ly p ipe-to-chassis clamp in the engine compartment Upper cover to the heater box, the 6 clips and the screws Instrument panel Hoses to the heater supply and return pipes

6.

Refill the cooling sy stem.

7.


8.

Op erate the engine to normal operating temperatures; then, chec k the climate control operation and check for leaks .

Valeo Style

1.


2.


3.

Remove or disc onnect the following: Hoses from the heater supply and return pipes. Using compressed air, blow the residual coolant from the heater core Instrument panel and the center console Pull off the temperature sensor heat exchanger, the left and right 2-pole couplings from the lower front of the heater box Pull the air ducts from the bottom of the heater box Crossmemb er and s trut from the front of the heater box Bracket from under the heater box Loosen the ignition switch housing-to-steering column bolt. Turn the ignition key to position 1, press the ignition switch housing locking button and pull the steering lock from the steering column Pull the air ducts from both sides of the heater box Heater box-to-chassis nuts and pull the heater box from the firewall Electrical connectors and clip from the blower motor. Disconnect the main air flap control cable from the heater box Heater box retaining clips and pull the front case from the rear case. Remove the heater core from the heater case Heater supply and return pipes-to-heater core screws and the pipes from the heater core

4.

Clean any spill ed coolant from inside the heater box. View of the heater box and related components — VALEO style — 300D Turbo, 300E, 300CE, 300TE, 300E, 4Matic, 300 TE 4Matic

Exploded view of the heater box and related components — VALEO style — 300D Turbo, 300E, 300CE, 300TE, 300E, 4Matic, 300TE 4Matic

To install: 5.

Install or connect the following: Heater supply and return pipes to the heater box using 3 new sealing rings Heater core into the heater box; make sure the rubber pipe grommets are seated properly Front case onto the heater box and secure with the clips Main air flap control cable to the heater box. Connect the electrical connectors and clip to the blower motor Position the heater box against the firewall (using a new seal) and install the heater box-to-chassis nuts. Air ducts to both sides of the heater box Slide the steering lock into the steering column and tighten the bolt Bracket under the heater box Crossmemb er and s trut at the front of the heater b ox Air ducts to the bottom of the heater box Temperature sensor heat exchanger, the left and right 2-pole couplings at the lower front of the heater box

6.


7.


8.



1.


2.

Dis charge and recover the air conditioning sy stem refrigerant.

3.


4.

Detach and plug the heater hoses from the firewall tube connections.

5.

Raise and safely sup port the vehic le.

6.

Remove or disc onnect the following: Panel behind the front right side member Move both front seats rearward and cover Floor mats from both sides of the vehicle Instrument panel and the center console Control unit, if equipped with ABS Left and right air ducts, from the rear passenger compartment, and the air ducts from the transmission tunnel, on the driver's floor 12-pole electrical connector for the temperature control from the right side of the heater/air conditioning box 5-pole and 6-pole electrical connectors from the temperature dial and the 2-pole electrical connector from the temperature sensor, air volume and the air distributing switch Vacuum lines from the air volume switch Heater/air conditioning box-to-stiffening strut screws Cable straps from the blower motor housing. Loosen the main cable harness straps from the heater/air conditioning box Pull the right and left air ducts from the fresh air nozzles on the heater/air conditioning box

7.

From the heater/air conditioning box, removing or disconnecting the following: 2-pole electrical connectors from both temperature sensors Electric lines cable connector sc rew Separate the electrical plug connector and unclip the coupling member from the holder

8.

Remove or disc onnect the following: Expansion valve; be sure to plug the openings Condensate drain hoses from both sides of the evaporator housing 2-pole electrical connector from the switch-over valve

9.

From the heater/air conditioning box, removing or disconnecting the following: Lower heater/air conditioning box-to-holding angle screws Angle bracket-to-blower housing nut Right side upper angle-to-chassis nut Left side upper angle-to-chassis nut

10.

Remove or disc onnect the following: Pull the heater/air conditioning box rearward to disengage the heater pipes from the front wall. Lift the heater/air conditioning box above the front passenger's leg room and remove from the vehicle; be sure to keep the heater pipes vertical so coolant will not drain out Evaporator housing and pull the heater core from the heater/air conditioning box To install: NOTE: When assembling the cases, be sure to seal them especially well along the horizontal separating joint. Pay particular attention to the areas behind the expansion valve and temperature or blower control.

11.

Install or connec t the following: Heater core and the ev aporator housing onto the heater/air c onditioning b ox Heater/air conditioning box against the front wall and position the heater pipes through the front wall Heater/air conditioning box to the left side upper angle bracket and screw Heater/air conditioning box to the right side upper angle bracket and nuts Lower angle bracket with screws 2-pole electrical connector to the switch-over valve Condensate drain hoses to the heater/air conditioning box

12.

Using refrigerant oil, lubricate the O-rings and threads; then, connect the refrigerant lines to the exp ansion valve.

13.

Install or connect the following: Electrical lines on the cable connector 2-pole electrical connectors to the temperature sensors Both fresh air duc t nozzles onto the heater/air conditioning box Main cable harness onto the heater/air conditioning box and secure with the cable straps Electric lines onto the blower housing and secure with the cable straps Stiffening strut and screws Vacuum lines to the air volume switch 2-pole, 5-pole and 6-pole electrical connectors onto the temperature dials 2-pole connector onto the flow sensor switch and the air distributing switch 12-pole connector onto the electronic switch gear Both heater air ducts for the rear passenger compartment Heater boxes ABS control unit, if equipp ed with ABS

14.


15.

Install or connect the following: Center console and the instrument panel Both foot mats into the leg room

Side member panel (located under the vehicle), if removed 16.


17.

Evacuate, charge and leak test the air conditioning sy stem.

18.



2.8L, 3.2L, 3.6L (104), 2.2L, 2.3L (111), 3.2L (112) and 4.3L (113) Engines

1.


2.

Remove or disc onnect the following: Negative b attery c able Access ory drive belt Engine under cover Alternator electrical wires

3.

Remove the alternator from the bottom. To install:

4.

Install the alternator assemb ly. Torque the mounting bolts to 31 ft. lbs . (42 Nm).

5.

Install or connect the following: Alternator electrical wires Engine under cover Access ory drive belt Connect the negative battery cable

6.

Start the engine and check for proper operation.


1.


2.

Remove or disc onnect the following: Negative b attery c able Viscous fan coupling if equipped with ball-type alternator Access ory drive belt Alternator electrical connections Alternator mounting bolts Alternator To install:

3.

Install or connect the following: Alternator assembly Electrical connections Access ory drive belt Viscous fan coupling Negative b attery c able

4.


6.0L (120) Engine

1.


2.

Remove or disc onnect the following: Negative b attery c able Access ory drive belt Alternator electrical connections AutoMatic transmission coolant pipe Engine under cover Right torsion bar and spring leaf rockers Alternator mounting bolts

3.

Remove the alternator from the bottom.

4.


To install:

Alternator assembly Right torsion bar and spring leaf rockers. Torque bolts to 44 ft. lbs. (60 Nm) AutoMatic transmission coolant pipe Alternator electrical connections Engine under cover Negative b attery c able Access ory drive belt 5.



All engines except the 4.2L and 5.0L engines are equipp ed with a Distributorless Ignition System (DIS). No adjustment is necessary. The 4.2L and 5.0L timing is controlled by the Electronic Ignition with Anti-Knock Retard (EZL/ARK) control unit. No ignition timing adjustment is possible.


All Models

1.


2.

Turn the steering wheel to full left position to gain access if necess ary.

3.

Remove or disc onnect the following: Negative ground cable Engine under cover Starter electrical connections Rear engine mount if necessary Starter mounting b olts Starter ass embly To install:

4.

Install or connect the following: Starter assembly. Torque the mounting bolts to 31 ft. lbs. (42 Nm) Rear engine m ount. Torque the bolts to 41 ft. lb s. (55 Nm) Starter electrical connections Negative ground cable

5.



1.


2.

Remove or disc onnect the following: Negative b attery c able Access ory drive belt Engine under cover Alternator electrical wires Alternator from the bottom of the vehicle To install:

3.

Install or connect the following: Alternator. Torque the mounting bolts to 31 ft. lbs. (42 Nm). Alternator electrical wires Engine under cover Access ory drive belt Connect the negative battery cable

4.



Safety is the most important factor when performing not only fuel system maintenance but also any type of maintenance. Failure to conduct maintenance and repairs in a safe manner may result in serious personal injury or death. Maintenance and testing of the vehicle's fuel system components can be accomplished safely and effectively by adhering to the following rules and guidelines.

To avoid the possibility of fire and personal injury, always disconnect the negative battery cable unless the repair or test procedure requires that battery voltage be applied. Always relieve the fuel system press ure prior to disconnecting any fuel sys tem component (injector, fuel rail, pressure regulator, etc.), fitting or fuel line connection. Exercise extreme caution whenever relieving fuel system pressure, to avoid exposing skin, face and eyes to fuel spray. Please be advised that fuel under pressure may penetrate the skin or any part of the body that it contacts. Always plac e a shop towel or cloth around the fitting or connection prior to loosening to absorb any exces s fuel due to spillage. Ensure that all fuel spillage (should it occur) is quickly removed from engine surfaces. Ensure that all fuel soaked cloths or towels are deposited into a suitable waste container. Always keep a dry chemical (Class B) fire extinguisher near the work area. Do not allow fuel spray or fuel vapors to come into contact with a spark or open flame. Always use a b ack-up wrench when loosening and tightening fuel line connection fittings. This will prevent unnecessary stress and torsion to fuel line piping. Always replace worn fuel fitting O-rings with new. Do not substitute fuel hose or equivalent, where fuel pipe is installed.


1.


2.


3.

Connect a fuel press ure gauge with a pressure release valv e to the serv ice port on the fuel suppl y rail.

4.

Place the fuel release tube into a container and open the valve.

5.

Remove the fuel pres sure gauge from the serv ice port on the fuel sup ply rail.


1.


2.


3.

Remove or disc onnect the following: Cover box Gas cap Fuel pump cover Pressure hoses Fuel filter

4.

Remove the connecting plug from the old filter and install it on a new filter using a new gask et.

5.


To install:

Fuel filter Attaching screws Pressure hoses Fuel pump cover Gas cap Cover box and check for proper sealing


All Models

1.


2.

Disc onnect the negative battery cable and properly relieve the fuel sys tem pressure.

3.

Remove or disc onnect the following: Intake, outlet and bypass lines. Plug the lines Electrical leads Fuel pump and vib ration pads To install: NOTE: Some models utilize 2 fuel pumps connected in series.

4.

Install or connect the following: Fuel pump and vib ration pads Electrical leads Intake, outlet and bypass lines. Torque the cap nuts and banjo bolts to 18–22 ft. lbs. (25–30 Nm). Typical fuel pumps and related components


All Models

1.


2.


3.

Remove or disc onnect the following: Negative b attery c able Brake servo vacuum hose Pressure regulator vacuum hose PCV hose Fuel feed pip e Fuel system electrical connections Left side ignition coil covers if necessary Fuel rail with the injectors attached Injector-to-fuel rail locking clip Injectors To install:

4.

Install or connect the following: Injectors with new O-rings on the fuel rail Injector-to-fuel rail locking clip Fuel rail/injector ass embly Left side ignition coil covers Fuel system electrical connections Fuel feed pip e PCV hose Pressure regulator vacuum hose Brake servo vacuum hose Negative b attery c able


Safety is the most important factor when performing not only fuel system maintenance but any type of maintenance. Failure to conduct maintenance and repairs in a safe manner may result in serious personal injury or death. Maintenance and testing of the vehicle's fuel system components can be accomplished safely and effectively by adhering to the following rules and guidelines.

To avoid the possibility of fire and personal injury, always disconnect the negative battery cable unless the repair or test procedure requires that battery voltage be applied. Please be advised that fuel under pressure may penetrate the skin or any part of the body that it contacts. Always plac e a shop towel or cloth around the fitting or connection prior to loosening to absorb any exces s fuel due to spillage. Ensure that all fuel spillage (should it occur) is quickly removed from engine surfaces. Ensure that all fuel soaked cloths or towels are deposited into a suitable waste container. Always keep a dry chemical (Class B) fire extinguisher near the work area. Do not allow fuel spray or fuel vapors to come into contact with a spark or open flame. Always use a b ack-up wrench when loosening and tightening fuel line connection fittings. This will prevent unnecessary stress and torsion to fuel line piping. Always replace worn fuel fitting O-rings with new. Do not substitute fuel hose or equivalent, where fuel pipe is installed.


These engines have electronically controlled idle speed, using a solenoid connected to the control unit. Idle speed and mixture adjustments are not recommended.


1.


2.

Loosen the center bolt while holding the filter cartridge. Remove cartridge.

3.

Lubric ate the gask et on the new filter cartridge.

4.

Install the new cartridge, washer, O-ring and bolt. NOTE: These Diesel engines utilize a self-bleeding fuel pump, therefore the priming pump has been eliminated. There is no need to bleed the system. Fuel filter assembly — Diesel engines


1.


2.

Dis connect the negative battery cab le. Remove the cover and loosen the central fastening bolt while holding the crankshaft with a socket wrench. Position the crankshaft pulley at 15 degrees ATDC. Fix the camshaft gear and injection pump in place with a cable strap.

3.


NOTE: The central fastening bolt uses left-hand threads.

Timing chain tensioner Fuel lines Idle Speed Control (ISC) solenoid vacuum lines and electrical connector Control rod travel sensor and actuator electrical cables Pump control lever throttle linkage Vacuum control valve 4.

Remove the injection pump s prock et bolt while holding the cranks haft in place. The bolt is a left-hand thread.

5.

Remove or disc onnect the following: Sprocket bolt Pump mounting bolts Injection pump while holding the timing device in place To install:

6.

Be sure the cranks haft is still at 15 degrees ATDC.

7.

Remove the timing plug from the pump .

8.

Using sp ecial tool 601 589 00 08 0 0 (serrated wrench) turn the pump until the lug of the governor is visib le through the hole.

9.

Install the sp ecial tool 601 589 0 5 21 00 (lock ing bolt) in the timing plug hole to prev ent the pump from turning while it is being installed.

10.

Install the pump on the engine. Torque the injection lines to 84 inch lbs.–15 ft. lbs . (10–20 Nm), mounting bolts to 15–18 ft. lbs . (20–25 Nm) and the central bolt to 30–36 ft. lbs. (40–50 Nm).

11.

Remove the locking bolt from the side of the injection pump.

12.

Install or connect the following: Vacuum control valve Pump control lever throttle linkage Control rod travel sensor and actuator electrical cables ISC solenoid vacuum lines and electrical connector Timing chain tensioner

13.

Crank the engine 1 revolution and recheck the TDC mark of the crankshaft and camshaft. Check the start of injector (injector pump timing) deliv ery with a digital tester. Install the locking bolt tool (023) to prevent the pump from turning during installation — Diesel engines


1.


2.

Disc onnect the negative battery cable and properly relieve the fuel sys tem pressure.

3.

Remove or disc onnect the following: Resonance intake pip e Fuel lines Injection pipes at nozzles Injection nozzles To install:

4.

Install or connect the following: Injectors with new O-rings. Torque to 30 ft. lbs. (40 Nm) Injection pipes at nozzles. Torque to 17 ft. lbs. (23 Nm) Fuel lines Resonance intake pip e Negative b attery c able


Remove the screw plug and install the injection timing position sensor

1.


2.

Remove the sc rew plug from the side of the injection pump governor housing.

3.

Install a position sens or into the hole and connect the tester to the vehicle battery and position sensor.

4.

Turn the cranks haft by hand until lamp s A and B on the tester light simultaneously. Take the reading on the crankshaft pulley.

5.

Loosen the injection pump and turn the adjusting screw until the timing pointer is at 15 degrees after TDC and both lamps are ON.

6.

Install the oil and plug. Torque the plug to 22 ft. lbs. (30 Nm). Turn the adjusting screw (arrow) to fine-tune the injection timing — Diesel engine


1997 2.2L engine Firing order: 1–3–4–2 Distributorless ignition system

Mercedes-Benz 2.3L engine Firing order: 1–3–4–2 Distributorless ignition system (coil on cylinder)

Mercedes-Benz 3.2L engine Firing order: 1–4–3–6–2–5 Distributorless ignition sy stem (coil on each cy linder–2 sp ark plugs per cyl.)

Mercedes-Benz 4.3L and 5.0L engines Firing order: 1–5–4–2 –6–3–7–8 D istributorless ignition system (coil on each cylinder–2 spark plugs per cyl.)

Intake manifold bolt tightening sequence — 4.2L and 5.0L (119) engines

Cylinder head bolt tightening sequence — 2.8L and 3.2L (104) Engines

Cylinder head bolt removal sequence — 2.2L and 2.3L (111) engines

Cylinder head bolt removal sequence — 3.2L (112) engine

Cylinder head bolt removal sequence — 4.3L (113) engine

Cylinder head bolt tightening sequence — 3.2L (112) engine

Cylinder head bolt tightening sequence — 4.3L (113) engine

Tightening sequence — 6.0L (120) engines

Cylinder head bolt tightening sequence — 6-cylinder Diesel engines


Several precautions must be observed when handling the inflator module to avoid accidental deployment and possible personal injury.

Never carry the inflator module by the wires or connector on the underside of the module. When carrying a live inflator module, hold securely with both hands and ensure that the bag and trim cover are pointed away. Place the inflator module on a bench or other surface with the bag and trim cover facing up. With the inflator module on the bench, never place anything on or close to the module, which may be thrown in the event of an accidental deployment.


To avoid personal injury when working on vehicles equipped with an air bag, the negative battery cable must be disconnected and insulated before working on the system. Failure to do so may result in accidental deployment of the air bag.


To rearm the air bag system, reattach the battery cable(s).


ALL MODELS

1.


2.


3.

Drain the power steering fluid.

4.

Remove or disc onnect the following: Fan clutch, fan and shroud Access ory drive belt Power steering lines at pump Oil c ooler lines if equipp ed Power steering pump Reservoir To install:

5.

Install or connect the following: Reservoir Power steering pump. Torque the mounting bolts to 18 ft. lbs. (25 Nm) Power steering lines Oil c ooler lines if equipp ed Access ory drive belt Fan clutch, fan and shroud

6.

Refill the reservoir with fresh fluid. Start the engine and turn the steering wheel from lock -to-lock sev eral times. The sys tem will bleed autoMatically. Check for leaks.


1.


2.


3.

Center the steering wheel and turn the key to the lock p osition. Remove the key from the ignition switch.

4.

Drain the power steering reserv oir.

5.

Remove or disc onnect the following: Fluid level feed line if equipped with level control Tie rod ends Pressure and return lines Steering gear return line Steering coupling heat shield Steering coupling Control valve connector if equipped with speed sensitive steering Steering gear retainer bolts (23g) Steering gear To install:

6.

Install or connect the following: Steering gear with new locking nuts. Torque to 36 ft. lbs. (50 Nm) Control valv e c onnector Control valve coupling. Torque the bolt to 15 ft. lbs. (20 Nm) Steering gear return line Pressure and return lines with new O-rings. Torque the fittings to 30 ft. lbs. (40 Nm) Heat shield Tie rod ends with new nuts. Torque the nuts to 44 ft. lbs. (60 Nm) Fluid level feed line Negative b attery c able

7.


8.

Check the front wheel alignment and adjust if neces sary. Exploded view of the rack and pinion steering gear mounting — E Class (210)


Exploded view of the worm and sector steering gear mounting

1.


2.


3.

Center the steering wheel and turn the key to the lock p osition. Remove the key from the ignition switch.

4.

Drain the power steering fluid reserv oir

5.

Remove or disc onnect the following: Trim p anel if necessary Drag link and tie rod Exhaust crossover pip e Steering gear heat shield Pressure and return lines Steering shaft Steering gear mounting bolts Steering gear To install:

6.

Center the steering gear by l ining up the mark on the sector shaft with the mark on the housing. CAUTION New stretch bolts must be used when installing the steering box and tightening the coupling. Align the mark on the shaft with the one on the housing to center the steering gear — worm and sector steering gear

7.

Install or connect the following: Steering gear Steering shaft. Torque the new stretch bolts to 52–59 ft. lbs. (70–80 Nm) Coupling bolt. Torque the bolt to 18 ft. lbs. (25 Nm) Pressure and return lines. Torque the pressure line to 18 ft. lbs. (25 Nm) and the return line to 26–30 ft. lbs. (35–40 Nm) Heat shield Exhaust crossover pip e Drag link and tie rod with new self-locking nuts Trim panel Negative b attery c able

8.



Front

SL CLASS (129)

1.


2.

Remove the front wheel.

3.

Supp ort the lower control arm.

4.

Using a sp ring compress or, compress the spring to relieve the pres sure on the lower control arm. NOTE: Convertible models have a vibration damper mounted on top of the left strut mount. Installation of the nut is possible only with the use of socket 124 589 00 09 00 and torque wrench 001 589 67 21 00.

5.

Remove or disc onnect the following: Upper mounting nut while holding the piston rod with a hex wrench ABS sensor wire Lower strut mounting bolts Strut assembly WARNING Do not allow the knuckle assembly to hang by the brake hose, ABS wire or brake pad sensor wire.

6.

Remove the upp er nut and remove the strut from the vehic le.

7.

If installing a new strut, transfer all components from the old strut to the new one.

8.

Clean the strut mounting surface of the knuc kle.

9.


To install:

Strut assembly. Torque the lower bolts only until the heads make contact Upper mounting bolt with washer and new self-locking nut. Torque until the surface of the knuckle makes contact with the strut 10.

Torque the 2 lower mounting bolts to 81 ft. lbs. (110 Nm), then tighten the upp er bolt to 147 ft. lbs. (200 Nm).

11.

Install the upp er mount. Torque a new hex nut to 45 ft. lbs. (60 Nm). On convertible models, b e sure the 0.00 8 inch (0 .2mm) thick steel washer is installed b elow the self-locking nut.

12.

Release the tension from the spring compress or. Be sure the upper and lower ends of the spring are properly seated. Exploded view of the front strut and related components — SL models

Rear

E320 WAGON (210)

1.


2.

Remove the upper strut mounting with the vehic le on the floor.

3.

Remove or disc onnect the following: Level control line if equipped Spring link cover Strut assembly To install:

4.

Install or connect the following: Strut assembly. Torque the lower self-locking nut to 41 ft. lbs. (55 Nm) Level control line. Torque to 18 ft. lbs. (25 Nm) Upper strut mounting nut. Torque to 22 ft. lbs. (30 Nm)


Front

ALL MODELS — EXCEPT E CLASS (210) 4-MATIC

1.


2.


3.

Supp ort the lower control arm with a jack. Raise the jack s lightly to release the tension on the shock absorber.

4.

Remove or disc onnect the following: Upper mounting Lower mounting bolt Shock absorber To install:

5.

Install or connect the following: Shock absorber Lower mounting b olt. Torque the bolt to 74 ft. lb s. (10 0 Nm). Upper mounting. Torque the lower nut to 11–13 ft. lbs. (15–18 Nm) and the upper nut to 22 ft. lbs. (30 Nm) Front wheel Front shock absorber mounting — S Class (A), C and E Class (B)

E CLASS (210) 4-MATIC

1.


2.

Remove or disc onnect the following: Front wheel Axle shaft 12-point nut Brake hose bracket Speed sensor and b rake lining sensor wires Tie rod end Supporting joint

3.

Pull the steering knuckl e outward and move the front axle out of the axle shaft flange.

4.

Separate the follower joint from the steering knuck le. Use wire to sup port the knuck le assemb ly.

5.

Remove or disc onnect the following: Engine undercover Axle shaft Stabilizer bar bracket Stabilizer bar end bushing

6.

Compress the coil sp ring and remove the upp er shock absorber mounting.

7.

Remove or disc onnect the following: Lower shock absorber mounting Shock absorber Coil s pring To install:

8.

Place the coil spring into position on the shock absorber. WARNING All susp ension fasteners that pass through a rubber bushing, should be tightened while the vehicle is at normal ride height. Premature bushing failure may occur if the fasteners are tightened while the suspension is hanging.

9.

Install or connect the following: Shock absorber upper and lower mounting. On the upper mounting, torque the bottom nut to 11–13 ft. lbs. (15–18 Nm) and the upper nut to 22 ft. lbs. (30 Nm). Torque the new self-locking nut on the lower mounting to 136 ft. lbs. (185 Nm) Stabilizer bar. Torque the bracket bolts to 15 ft. lbs. (20 Nm) Axle shaft Engine undercover

NOTE: Ensure that the axle shaft is in the proper position before connecting the follower joint. 10.

Install or connect the following: Follower joint with new self-locking nut. Torque nut to 33 ft. lbs. (45 Nm) Supporting joint with new self-locking nut. Torque nut to 77 ft. lbs. (105 Nm) Tie rod end with new self-locking nut. Torque nut to 44 ft. lbs. (60 Nm) Speed and brake lining sensor wires Brake hose bracket New axle shaft 12-point nut. Torque to 162 ft. lbs. (220 Nm). Secure the nut with caulk (nut lock) so there is no gap between the groove and locking tab Front wheel Exploded view of the front shock absorber/coil spring mounting — 210 4-MATIC

Rear

ALL MODELS

1.


2.

Supp ort the lower control arm. WARNING Be sure that the piston rod does not turn when the removing the nut. The mount for the operating piston may loosen and release the gas and oil from the shock absorber.

3.

Remove or disc onnect the following: Upper shock absorber mounting nuts Rollover bar switch on convertible models Lower control arm cover Lower shock absorber mounting bolt Shock absorber To install:

4.

Install or connect the following: Shock absorber Lower mounting bolt. Torque to 40 ft. lbs. (55 Nm) Lower control arm cover Rollover bar switch

5.

Lower the vehicle and ins tall the spacer, upp er bushi ng, washer and new self-locking nuts. Torque the bottom nut to 11–13 ft. lbs . (15–18 Nm) and the upp er nut to 22 ft. lbs . (30 Nm).


Front

ALL MODELS — EXCEPT 4-MATIC

1.


2.


3.

Compress the coil sp ring with an internal sp ring compres sor.

4.

Remove the sp ring and upp er seat towards the front of the vehic le. To install:

5.

Clean the spring mounting area on the lower control arm.

6.

Compress the spring and position the spring on the control arm with the upp er seat.

7.

Carefully release the sp ring compres sor until the sp ring is installed in the correct position.

8.

Install the front wheel.

E CLASS (210) 4-Matic

Refer to the shock absorber removal and installation procedure for coil spring service.

Rear

ALL MODELS

1.


2.

Remove or disc onnect the following: Rear wheel Rollover bar switch on the SL Class Lower control arm cover Cross brace Brake lining sensor wire

3.

Jack up the lower control arm until the axle shaft is horizontal. Be careful not to raise the vehic le off the lift.

4.

Compress the spring with an internal sp ring compress or. Do not use air tools to compres s the sp ring.

5.

Loosen the bolt securing the lower control arm to the axle carrier. Remove the spri ng with the lower mount.

6.

Clean the sp ring mounting surface.

7.

Position the sp ring on the lower control arm and release the sp ring compress or.

8.

Remove the jack from the lower control arm.

9.


To install:

Brake lining sensor wire Cross brace Lower control arm cover Rollover bar switch Rear wheel 10.

Torque the lower control arm-to-axle carrier nut to 52 ft. lbs. (70 Nm).


Front

ALL MODELS

1.


2.

Remove or disc onnect the following: Torsion bar brackets Spring swiv eling lever and mounting plate if equipp ed Torsion bar To install:

3.

Install or connect the following: Torsion bar and brackets with new bushings. Torque the bracket bolts as follows: Control arm bracket self- locking nuts: 15 ft. lbs. (20 Nm) Top spring s wiveling lever brack et self-locking nuts: 30 ft. lbs. (40 Nm) Bottom spring swiveling lever bracket self-locking nuts: 15 ft. lbs. (20 Nm) Torsion bar-to-frame bracket self-locking bolts: 44 ft. lbs. (60 Nm)

Rear

ALL MODELS

1.


2.

Properly relieve the fuel sys tem pressure on SL Class vehicles.

3.

Remove or disc onnect the following: Rear axle housing assemb ly Torsion bar connecting rods Torsion bar brackets Fuel-tank-to-pump hose on SL Class Intermediate lever Torsion bar To install:

4.

Install or connect the following: Torsion bar and brackets with new bushings. Torque the bracket nuts to 15 ft. lbs. (20 Nm) Intermediate lever. Torque the self-locking nuts to 84 inch lbs. (10 Nm) Fuel-tank-to-pump hose Torsion bar connecting rods. Torque the self-locking nuts to 30 ft. lbs. (40 Nm) Rear axle housing assemb ly


All Models NOTE: The upper ball joint is an integral part of the upper control arm. Control arm replacement is necessary if the ball joint becomes worn or damaged.

1.


2.

Remove the front wheel and sup port the lower control arm with a jack.

3.

Remove or disc onnect the following: Electrical connections if equipped Ball joint stud Control arm mounting bolts Bearing shell To install:

4.

Install or connect the following: Control arm in the bearing shell. Torque the self-locking nut to 55 ft. lbs. (75 Nm) after the weight of the vehicle is on the suspension Control arm assembly using new micro-encapsulated bolts. Torque the bolts to 37 ft. lbs. (50 Nm) Ball joint stud. Torque the nut to 88 ft. lbs. (120 Nm). Fill the gap in the clamp with a wax-like protectant.

5.

Front wheel

6.

Lower the vehicle to the floor and tighten the control arm through-bolt and nut to the sp ecific ation. Steering knuckle (5), control arm (6), bolt (6c) and nut (6g) — S Class (140) and C Class (202)


C Class (202), CLK (208), S Class (140) and SLK 230 (170)

1.


2.

Remove or disc onnect the following: Front wheel Disc brake rotor securing b olt and back ing plate bolt Ball joint nut Ball joint-to-steering knuckle nut Ball joint To install:

3.

Install or connect the following: Ball joint. Torque the control arm nut to 74 ft. lbs. (100 Nm) and the knuckle nut to 104 ft. lbs. (140 Nm). Backing plate bolt. Torque to 72 inch lbs. (8 Nm) Brake rotor bolt. Torque the bolt to 84 inch lbs. (10 Nm) Front wheel Common ball joint — C Class (202) and S Class (140)

Sl Class (129) and E class (210) — Except 4-Matic NOTE: The ball joint on vehicles with engines 104 and 119 cannot be pressed out of the control arm. They have been welded in place. In this case, replace the control arm assembly.

1.


2.

Remove or disc onnect the following: Front wheel Coil s pring Stabilizer bar and bracket Lower control arm-to-frame nuts and bolts Ball joint pinch bolt and nut Lower control arm Ball joint using a press To install:

3.

Install or connect the following: Ball joint using a press Control arm. Temporarily tighten the control arm-to-frame nuts Ball joint pinch bolt and nut. Torque the nut to 92 ft. lbs. (125 Nm) Stabilizer bar bracket. Torque the bolts to 15 ft. lbs. (20 Nm) Coil s pring Front wheel

4.

Lower the vehic le to the floor. Torque the control arm-to-frame nuts to 88 ft. lbs . (120 Nm).

E Class 4-Matic (2 10)

1.


2.

Remove or disc onnect the following: Front wheel Axle shaft 12-point nut (61) Ball joint nut. Press the ball joint out of the steering knuckle (5)

3.

Pull the steering knuck le outward and remove the axle shaft (60) from the flange.

4.

Supp ort the knuc kle assemb ly by plac ing a block of wood (arrow) between the coil spring and the knuc kle.

5.

Position the axle shaft out of the way using a piece of wire.

6.

Remove the nut and pres s the ball joint (7) out of the lower control arm (4). To install:

7.

Install or connect the fo following: llowing: Ball joint. Torque a new self-locking nut to 77 ft. lbs. (105 Nm) Axle shaft Ball joint to the steering knuckle with a new self-locking nut. Torque the nut to 77 ft. lbs. (105 Nm) 12-point axle nut. Torque to 162 ft. lbs. (220 Nm) Front wheel Lower ball joint mounting — E Class 4-Matic (210)


Front

1.


2.

Remove the the front front wheel and sup port the the lower lower control control arm with a jack.

3.

Remove or disc onnect the fo following: llowing: Electrical connections if equipped Ball joint stud Control arm mounting bolts To install:

4.

Install or connect the fo following: llowing: Control arm assembly using new bolts. Torque the bolts to 37 ft. lbs. (50 Nm) Ball joint stud. Torque the nut to 88 ft. lbs. (120 Nm). Electrical connections

5.

Front wheel

6.

Lower the veh vehic icle le to the floor floor and tighten the the control arm bolt and nut.


Front

1.


2.

Remove the the front front wheel and sup port the the lower lower control control arm with a jack.

3.

Remove or disc onnect the fo following: llowing: Upper control arm Steel spacer washers

4.

Using appropriate removal to tool, ol, remove the bus hings from from the the contro controll arm. To install:

5.

Install the bus hings using using appropriate installation tool.

6.

Install or connect the fo following: llowing: Steel spacer washers Upper control arm


C Class (202), CLK (208), S Class (140) and SLK 230 (170)

1.


2.

Remove or disc onnect the following: Front wheel Disc brake rotor securing b olt and back ing plate bolt Ball joint nut Ball joint-to-steering knuckle nut Control arm To install:

3.

Install or connect the following: Control arm assembly. Torque the control arm nut to 74 ft. lbs. (100 Nm) and the knuckle nut to 104 ft. lbs. (140 Nm). Backing plate bolt. Torque to 72 inch lbs. (8 Nm) Brake rotor bolt. Torque the bolt to 84 inch lbs. (10 Nm) Front wheel

SL Class (129) and E class (210) — Except 4-Matic

1.


2.

Remove or disc onnect the following: Front wheel Coil s pring Stabilizer bar and bracket Lower control arm-to-frame nuts and bolts Ball joint pinch bolt and nut Lower control arm To install:

3.

Install or connect the following: Control arm. Temporarily tighten the control arm-to-frame nuts Ball joint pinch bolt and nut. Torque the nut to 92 ft. lbs. (125 Nm) Stabilizer bar bracket. Torque the bolts to 15 ft. lbs. (20 Nm) Coil s pring Front wheel

4.

Lower the vehic le to the floor. Torque the control arm-to-frame nuts to 88 ft. lbs . (120 Nm).

E Class 4-Matic (2 10)

1.


2.

Remove or disc onnect the following: Front wheel Axle shaft 12-point nut Ball joint nut. Press the ball joint out of the steering knuckle Axle shaft from the flange

3.

Support the knuckle assembl y by p lacing a block of wood between the coil spring and the knuckle.

4.

Position the axle shaft out of the way using a piece of wire.

5.

Remove the lower control arm ass embly To install:

6.

Install or connect the following: Ball joint. Torque a new self-locking nut to 77 ft. lbs. (105 Nm) Axle shaft Ball joint to the steering knuckle with a new self-locking nut. Torque the nut to 77 ft. lbs. (105 Nm) 12-point axle nut. Torque to 162 ft. lbs. (220 Nm) Front wheel


1.


2.


3.

Using appropriate removal tool, remove the bus hings from the control arm.

4.

Install the bus hings using appropriate installation tool.

5.

Install the lower control arm ass embly

Lower control arm

To install:


1.


2.

Supp ort the lower control arm assem bly.

3.

Remove or disc onnect the following: Rear wheel Electrical connections if equipped Shock absorber Lower control arm To install:

4.

Install or connect the following: Lower control arm. Torque the bolts to 40 ft. lbs. (54 Nm). Shock absorber. Torque the mounting nut to 52 ft. lbs. (70 Nm) Electrical connections Rear wheel


1.


2.

Remove or disc onnect the following: Rear wheel Lower control arm

3.

Using a pres s, remove the rubb er mount from the sp ring link .

4.

Install the rubb er mounts using a pres s.

5.


To install:

Lower control arm Rear wheel


Front

ALL MODELS EXCEPT E CLASS 4-MATIC (210)

1.


2.


3.

Install 1 wheel bolt (48a) in the flange on the opposite side of the lock ing bolt.

4.

Push the brake pads into the caliper until they are clear of the rotor.

5.

Remove the grease cap (9e).

6.

Loosen the bolt (9i) and tighten the clamping nut (9d) while turning the rotor until all bearing play is elim inated.

7.

Loosen the clamp ing nut until play is detectable.

8.

Mount a dial indicator (022) on the hub with the measuring tip on the end of the spi ndle.

9.

Turn the clamp ing nut to adjust the play while pul ling and pus hing on the rotor to measure the bearing play. Correct bearing play should be 0.000 4–0.00 08 inc hes (0.01 –0.02mm).

10.

Torque the bolt on the clamping nut to 96 inch lb s. (12 Nm) and recheck the bearing pl ay again. If the play is within sp ecific ation, assembl e the wheel. If not, repeat the procedure. Mount a dial indicator on the rotor to measure the bearing play — except E Class 4-Matic

E CLASS 4-MATIC (210)

The front wheel bearings on the 4-Matic are not adjustable. If the bearings become loose or make noise, they must be replaced.


Front

ALL MODELS EXCEPT E CLASS 4-MATIC

1.


2.

Remove or disc onnect the following: Front wheel Brake caliper and rotor Grease cap Clamping nut and washer Wheel hub Grease seal Bearing To install:

3.

Install or connect the following: Bearing Grease seal Wheel hub Washer and clamping nut

4.

Adjust bearing play. Torque the clamp b olt to 96 inch lbs. (12 Nm)

5.

Fill the grease cap to the flared edge with high temperature roller bearing grease and install the cap.

6.

Install or connect the following: Rotor and caliper Front wheel Exploded view of the front wheel bearing assembly — S Class (140), SLK 230 (170), C Class (202), CLK 320 (208) and E Class (210)

E CLASS 4-MATIC (210)

Steering knuckle and related components — E Class 4-Matic (210)

1.


2.

Remove or disc onnect the following: Front wheel 12-point axle nut (61) Front axle distributor connector Speed and brake lining sensor wires. Position out of the way Brake disc (34) Splash shield (35) Speed sensor and bracket (5f) Tie rod end (10a) Ball joint (7) Follower joint (8 )

1998 Mercedes Benz SLK230 Workshop Manual

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