Common Rail Fuel System - CM850 QSC and QSL

HHI HHI Trainin g Center

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• Similar to QSB ’02 fuel system except the high pressure fuel pump is designed and made by Cummins – Allows multiple injection events per cylinder firing . • Pilot • Main • Post

– Capable of higher injection pressures than current CAPS system. – Injection event is not coupled with a mechanical system such as a fuel pump rotor or an injector cam. – Design is simple and easier to service. – Lower chance of a single failure leaving a customer stranded (example: (e xample: Rotor Seizure, or ICV Failure). – Repair costs are lower; it is not necessary to replace the entire system. – Can be used on multiple engine platforms (midrange, heavy duty, and high horsepower). – New fuel system is a major component component of the advanced combustion technology being used to reduce emissions. HHI HHI Trainin g Center

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Fue uell Sys ystem tem La L ayo yout ut Fuel Pump Drain Line

High Pressure Relief Valve Drain Line Injector Drain Line

Fuel Pump

ECM Cooling Plate HHI HHI Trainin g Center

ECM

2 micron Fuel Filter 3

Fuel System Layout

Fuel Drain Connection

Fuel Lift Pump Fuel Supply Connection ECM Cooling Plate Check Valve HHI HHI Trainin g Center

ECM Cooling Plate 4

Fuel System Layout

3 micron fuel filter


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Fuel Sys Systt em Flow Flo w 8 - Fuel Fuel Inle Inlett to to High Pressure Pump

6 - Fuel Fuel Inle Inlett to Fuel Filter

7 - Fuel Fuel Outl Outlet et From Fuel Filter 1 - Fuel Fuel Inle Inlett

4 - Fuel Fuel Inle Inlett to to Gear Pump 5 - Fuel Fuel Outl Outlet et From Gear Pump HHI HHI Trainin g Center

3 - Fuel Fuel Outl Outlet et From From 2 - Fuel Fuel Inle Inlett to ECM ECM Cooling Plate Cooling Plate 6

Fuel Sys System tem La L ayo yout ut High Pressure Pump Head

Fuel Pump Actuator Housing

Fuel Pump Actuator

High Pressure Outlet Fitting

Gear Pump Inlet

Cam Housing Gear Pump Outlet Fuel Gear Pump HHI HHI Trainin g Center

Inlet Restriction Service Port 7

• The primary purpose of the priming circuit is to provide pressure to the gear pump for quick engine starts. • The fuel lift pump only runs for 30 seconds at key-on. It is only used for priming the fuel system at start-up. • The priming pump will fill the pressure side filter when installed dry. 5 or 6 key cycles is required to fill the the pressure side filter. • The lift pump does not do a good job of priming a dry system. It is recommended that the suction filter be pre-filled with clean fuel when replaced.


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Fuel Lift Pump Check Valve

Lift Pump Inlet Lift Pump Outlet


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• Without the ECM cooling plate check valve, fuel would continuously circulate through the ECM cooling plate when the lift pump is not running.

da maged upon installation. • The check valve can become damaged Inspect the check valve for damage or debris when troubleshooting low power and performance problems. • High fuel inlet restriction will be measured at the gear pump inlet if the check valve is damaged.

Check Valve HHI HHI Trainin g Center

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• High pressure relief valve acts like a ‘fuse’ in the fuel system. • If fuel pressure exceeds the relief valve pop-off pressure, fuel rail pressure will be regulated to 900 bar and the excess fuel will be returned to drain. • If the high pressure relief valve opens, fault code 449 or 2311 will activate indicating a pressure overshoot occurred.

High Pressure Relief Valve


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All low pressure fuel supply lines have ‘quick connect’ fittings. The ‘tabs’ must be pushed in to release the connector from the fitting. Flexible lines must be routed properly to allow engines to run and to prevent damage. Removal Removal of supply supply lines from from high high pressure pressure pump pump is easier easier if all 3 lines are disconnected.

• NOTHING may be permitted to rub r ub against lines!

Release Tabs


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Fuel at high pressure is conveyed to each injector by its high pressure fuel connector. Injector Solenoid Leakage

HPC to Injector L eakage eakage

Leakage fuel from the match fits in the injector and injector solenoid travels through a drilling in the cylinder head and exits at the rear of the cylinder head.

Match Match Fit Leakage

A damaged high pressure fuel connector-to-injector interface will result in excessive drain flow from the back of the cylinder head. HHI HHI Trainin g Center

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With a High Pressure Common Rail fuel system, stuck open injectors will cause continuous injection in the cylinder. This is caused caused by debris debris in the fuel fuel system system being transferr transferred ed to the injector. The engine will smoke, knock loudly, and possible die if an injector sticks open. Caused by debris in the injector holding the injector needle open. op en. Fixture an injector in the ENCORE pop-tester if suspected to be stuck open.


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Avoid Failures: Orient inlet feature toward HPC Follow T&R Manual (seat injector completely, use holding clamp to index injector, injector, do not not “side “side load” injector injector clamp clamp but finger tight both bolts first so that the clamp is centered on the injector) “Feel” “Feel” the HPC HPC engage the injector injector Always use proper torque on the HPC jam nut ALWAYS replace the HPC when installing a new injector. Be cautious of generated debris (shipping plugs, plant cleanliness, part cleanliness). HHI HHI Trainin g Center

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• • • • • • • • • • • • • • • • • •

Fuel Pump Head Capscrews “Racetrack” o-ring Fuel Pump Head o-ring Fuel Pump Mounting Seal Oil supply o-ring (at gear housing) Fuel Pump Actuator Housing Fuel Pump Actuator Housing Capscrews Fuel Pump Actuator Housing Gasket Fuel Pump Actuator Fuel Pump Actuator Capscrews Fuel Pump Actuator o-rings Fuel Pump (Gear Pump) Gear Pump Gasket Gear Pump Capscrews Gear Pump Drive Coupling Outlet Fitting (Male Union) Outlet Fitting Seal Washer High Pressure Pump Tappet Assemblies


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• CAPS System – Many sophisticated electronic parts in the pump – When all else failed, changing the fuel pump was often the solution

• High Pressure Common Rail System – Simple design with no sophisticated electronics – Fuel pump is not a cure-all for fuel system problems

• The functions that were performed by the CAPS pump have been split up into several components – Accumulator → High Pressure Fuel Rail and Fuel Lines – Injection Control Valve → 6 Injector Solenoids – Pumping Control Valve → Fuel Pump Actuator – Distributor Module and Rotor → 6 Injector Solenoids

• Proper diagnostics to the exact failed component is the key. Changing the fuel pump is no longer the ‘cure-all’ for the High Pressure Common Rail Fuel System • Over 20,000 hours of field test experience with only minor fuel system issues 19 HHI HHI Trainin g Center

• Maximum Inlet Restriction at OEM Connection Point – 4inHg (clean suction filter) – 8inHg (dirty suction filter)

• Maximum Restriction at Gear Pump Inlet Point – 10 inHg (dirty suction filter)

• Minimum lift pump pressure while cranking (for starting) – 5 PSI (at cranking)

• Maximum Pressure Filter Pressure Drop – 20 PSI (dirty filter)

• Minimum gear pump pressure while cranking (for starting) – 10 PSI

• Minimum gear pump pressure at “rated” speed – 90 PSI (filter inlet) HHI HHI Trainin g Center

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• Normal Operating Pressure in Accumulator – 300 300 - 1600 1600 bar (4,3 (4,350 50 - 23,2 23,200 00 psi psi))

• Maximum MDV Leakage (performance troubleshooting) – 1 drop per second maximum

• Maximum Injector Leakage (performance troubleshooting) – 1500 bar, engine idle, measure 300 cc: no less than 45 seconds – Crank the engine for 30 seconds: no more than 100cc (~150cc is 100% of pump output at 150rpm) – If cranking faster, spec at cranking may be less valid?... for 400 RPM, total pump output is ~400cc

• Maximum HPP Leakage (performance troubleshooting) – 1500 bar, engine idle, measure 300 cc: no less than 30 seconds – Note that pump drain flow also includes “air-bleed” – Crank the engine for 30 seconds: no more than 150cc – If cranking faster, spec is definitely invalid!


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Fault code 2215 indicates that measured fuel pressure in the fuel rail cannot meet commanded fuel pressure from the ECM. Several different failure modes can cause this fault code. – High fuel inlet restriction • Plugged suction fuel filter • ECM cooling plate check valve broken or plugged • OEM fuel supply lines collapsed, damaged, or blocked.

– Failed gear pump (low pressure output) – High leakage • Loose HPCs • Damaged HPC-to-injector joint • Stuck open fuel injector • High pressure pump head drain flow excessive

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Replacing a failed component, the engine must run to clear the fault and the ECM must have a successful power-down cycle. – A successful power-down cycle consists of turning the keyswitch power off and waiting 10 seconds before removing the main ECM power.


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• Tools necessary to troubleshoot the high pressure common rail fuel system include: – M10 Compuchek Fittings (measure pressure or vacuum) – 0.043” Orificed Diagnostic Fuel Line (create rated r ated flow without dyno) – 0-30 inHg Vacuum Gauge (measure inlet restriction) – Diagnostic T-Adapter (allows measuring pressure while having wastel wasteline ine at outle outlett of filte filter) r) – 0-200 PSI pressure gauge (measures gear pump pressure) – M12 Drain Flow Adapter (measures leakage from high pressure components) – Fuel Rail “Blocker” (for injector isolation) – INSITE or CALTERM (to raise pressure for leakage tests) – INSITE or CALTERM (to perform cylinder cut-out)


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Procedure – Install a Compuchek fitting and the 0.043 ” orificed diagnostic fuel line at the pressure filter. – Install a Compucheck fitting and and the 0-30 inHg vacuum vacuum gauge at the point where restriction is to be measured. – Operate the engine at high idle and measure vacuum.

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When to Perform Test – FC2215 – Low power complaints

Fuel Inlet Restriction Measurement Port HHI HHI Trainin g Center

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• Procedure – Install CUC fitting and diagnostic T-Adapter at the pressure filter outlet – Install the pressure gauge and the 0.043” orificed diagnostic fuel line at the T-Adapter

Fu el Fi l t er In l et

Fu el Fi l t er Ou t l et

– Operate the engine at idle

• When to Perform Test – FC2215 – Low power complaints – Engine will not start (without wasteline)


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Procedure – Install Compuchek fitting and the 0.043 ” orificed diagnostic fuel line at pressure filter outlet (P/N 3164621) – Route the output of the 0.043 ” orificed diagnostic fuel line into a bucket – Operate the engine at idle.

collection bucket until the outlet outlet of the fuel line is – Allow fuel to fill the collection submerged – Check for excessive amounts of air bubbles exiting the fuel line

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When to Perform Test – Surge (continuous surging) – Engine difficult to start / loss of prime


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Procedure – Install drain flow adapters for the high pressure relief valve, high pressure pump, and injectors. (P/N3164618) – Route fuel lines from the flow adapter to a bucket – Operate the engine at idle and begin the INSITE ‘High Pressure Leakage Test” t – Measure the drain flow from each device into a graduated cylinder – Use “blocker” tool to isolate injector/HPC leakage if necessary (P/N3164325)


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• When to perform test – FC2215 – No start and can not build rail pressure (perform test while cranking)

• HPP Failures: – HP Seal Leaks to Drain, Pump Head Cracks, Severe B/P Leakage

• Injector Failures: – Injector body cracked – P.V. severe erosion

• HPC Failures: – Poor seal with injector

• High Pressure Relief Valve Failures: – Valve seat leaks – Broken Spring

• High Pressure Lines: – Observe fuel seepage at high pressure


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• Fault Code 2215: Pressure is low – Fuel pressure is lower than commanded (2311, 449, and 275 are inactive)

• Fault Code 2216: Pressure is high – Fuel pressure is higher than commanded but still under pressure relief valve opening pressure.

• Fault Code 275: – Bank pressure deviation of the fuel pump. Replace fuel pump head.

• Fault Code 271 and 272: – Fuel pump actuator open or short circuit

• Fault Code 2311: Fuel pump actuator circuit error – Open or short circuit – Resistance high or low – Fuel rail pressure has exceeded 1950 bar and pressure relief valve has opened with circuit errors detected on the fuel pump 29 HHI HHI Trainin g Center

• Fault Code 449: Pressure high (relief valve) – Fuel rail pressure has exceeded 1950 bar and pressure relief valve has opened with no circuit errors detected.

• Fault Code 451 and 452 – Fuel pressure sensor out-of-range circuit errors

Se nsor In-Range • Fault Code NEW: Fuel Pressure Sensor – If fuel pressure sensor signal is noisy this diagnostic will prevent pr event NTF pump replacement. – This failure mode will cause fault codes 2215 and a nd 275.

• Fault Code 268: Stuck-in-range error – If fuel pressure sensor signal stops updating (has “0 noise”), the sensor is failed … this may lead to other fault code detection (example: loss of signal may cause fuel rail pressure relief r elief valve to open and then fault code 2215?).

• Injector Circuits • Injector UFD HHI HHI Trainin g Center

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Injector


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Plastic clamps hold yellow & orange wires and red & brown wires 2

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Three sets of internal injector wiring provides power to the injectors.

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Polarity does not matter when connecting the wiring to the injector.


Plastic tube protects wires from casting

Wire tie holds yellow & orange wires to reduce extra length

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Hold leads so that they can not “flare out” where they may short against a rocker lever or brake housing.


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Incorrect Installation

Correct Installation

ISC

Lube Oil & Filter

15,000 mi, 500 hr, or 6 months

Fuel Filters Coolant Change Overhead Set


15,000 mi, 500 hr,

ISL 20,000 mi, 500 hr, or 6 months 20,000 mi, 500 hr,

or 6 months

or 6 months

72,000 mi, 2000 hr, or 2 years

80,000 mi, 2000 hr,

150,000 mi, 5000 hr, or 4 years

150,000 mi, 5000 hr, or 4 years

or 2 years

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• Tappet Tool Kit • Tappet Tool Trough • Cam Gear Tool • Fuel Rail Blocker • Leakage Test Tool • Injector Installer • Fuel Waste Line • HPC Remover • Wire Repair Kit

3165088 3165086 3165093 3164325 3164618 N/A 3164621 3164025 3165117

Required Required Required Required Required Productivity Productivity Required Required

One or the other is required

– Add-on to ISB ’02 Kit – Only 7 pieces


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• ISC & ISL Base Engine T&R

4021418

• ISC & ISL With CM850 Fuel System & Electronics T&R

4021416

• Wiring Diagram

4021421

• Warranty Fail Code Manual

3666255

• ISC SRT Manual

3666030

• ISL SRT Manual

4021423


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Common Rail Fuel System - CM850 QSC and QSL

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