FORM NO. SENR2253-01 FOR USE IN SERVICE MANUALS: 950B WHEEL LOADER, SENR2249 215 EXCAVATOR, SENR7421 225 EXCAVATOR, REG01578 518 SKIDDER, REG00971 120G MOTOR GRADER, REG01654 130 & 140G MOTOR GRADERS, REG01652
SYSTEMS OPERATION TESTING AND ADJUSTING
3304 DIRECT INJECTION VEHICULAR ENGINE WITH NEW SCROLL FUEL SYSTEM 7Z 9Z 12Z
3304 DIRECT INJECTION VEHICULAR ENGINE WITH NEW SCROLL FUEL SYSTEM
INDEX
SYSTEMS OPERATION Air Inlet and Exhaust System Head, Cylinder.. .. .. System, Air Inlet and Exhaust Turbocharger. . . . . . . . . . . . . . . . . . . . ............. .. Valves , .. . . .. .. Valve Mechanism.....................................
15 14 14 15 15
Basic Block Block, Cylinder.. . . . .. .. .. .. .. .. .. .. .. .. . . .. . . . . . . Crankshaft ,.. Pistons................ .. Rings, Piston Rod, Connecting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
20 20 20 20 20
Cooling System Coolant Flow...... .. .. Cooling System Components. . . . .
18 19
.. .. . . . . . . . . . .
Electrical System Charging System Components Other Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Starting System Components. . . . . . . .. . . . . . . . . . . . . .. Engine Design. . . . . . . . . . . . . . . .. . . . . . . . . . .. ... . .. .. . . .
21 22 21 4
Fuel System Control, Air Fuel Ratio.. . .. . .. Fuel Flow............................................. Governor............................................. Nozzle, Fuel Injection. . . . . . . . . . . . . . . . . . . . .. . . ...... Oil Flow for Fuel Pump and Governor.. .. .. Pump. Fuel Injection.................. . . . . . . . . . . . . . . . . Pump, Fuel Transfer
12 5 9 6 8 5 7
Lubrication System System Oil Flow
16
TESTING AND ADJUSTING
Air Inlet and Exhaust System Air Inlet and EXhaust, Measurement of Restriction. . . . .. Camshaft Lobes, Measurement Procedure. . .. .. .. . . . . .. Exhaust Temperature, Measu rement of. . . . . . . . .. .... . .. Head, Cylinder. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Inlet Manifold Pressure, Measurement of .. .. .. .. Pressure, Crankcase (Crankshaft Compartment) . . . . . . .. Valve Clearance
58 60 58 59 58 59 59
Basic Block Bearings, Connecting Rod. . . . . . . . . . . .. . . .. .. . . . . . . . . .. Bearings, Main. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. Block, Cylinder...... .. Flywheel Gauge, Piston Ring Groove , Housing, FlyWheel Pistons Rod, Connecting. . . . . . . . .. . . . . . . . . . . .. . . . . . . . . ..
66 66 67 67 66 67 66 66
Cooling System Chart, V-Belt Tension. Cooling System, Leak Test , Cooling System, Test Tools... .. Cooling System, Testing................ . ... Cooling System. Visual Inspection................... .. Pressure Cap, Testing.. Radiator, Leak Testing......... . .. .. .. Regulator, Water Temperature. . . . . . . . . . .. . . . . . . . . Relief Valve, Testing Thermostat. . . . . . . . . . . . . .. . .. . . . . . . . . . . . . . . . . ..
65 64 63 63 63 64 64 65 64 65
Electrical System Battery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Charging System Starting System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
71 71 72
Fuel System Control, Air Fuel Ratio; Governor Adjustment Cylinders, Engine; Checking Separately. . . . . . . . . . . . Engine Speed Measurement. . . . . . . . . . . . . . . . . . . . . .. Fuel Injection Pumps, Removal and Installation of Fuel Setting Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. Governor, Adjustments. . . ... . .. .. ... . . . . . . . . . . . . . . . . .. Inspection, Fuel System. . . . . . . . . . . .. . . . . . . . . . . . . . .. Lines, Fuel Injection Nozzles, Fuel Injection; Testing , Pump, Injection; Plunger and Lifter Check Timing Check, 6V31 00 Engine Timing Indicator Group.. Timing Check, Timing Pin Method. . . . . . ... . . . . . . . . . . .. Top Center Compression Position for No.1 Piston .....
46 35 54 40 49 55 35 40 36 40 43 44 42
Lubrication System Bearing Wear............. .. .. .. .. Oil Consumption , .. .. . . . . . . . . . . .. Oil Pressure, High Oil Pressure, Low.. .. . .. . . . . . . . . . . .. . . .. .. .. . . . .. ..
62 61 62 61
Troubleshooting. . . . . . . . . . .. . . . . . ... . . . . . . . . . . . . . . . . .. ..
23
3
ENGINE DESIGN
Bore Stroke Number of Cylinders Cylinder Arrangement Firing Order (Injection Sequence) Direction of Rotation (when seen from flywheel end) *No. 1 Cylinder is Opposite Flywheel End.
120.7 mm (4.75 in.) 152.4 mm (6.00 in.) 4 *in-line
1,3,4,2
'-'
Counterclockwise
EXHAUST VALVES
1
2
1 A76353X 1
3
2
4
3
4
INTAKE VALVES
CYLINDER AND VALVE IDENTIFICATION
---
4
SYSTEMS OPERATION
FUEL SYSTEM
FUEL SYSTEM FUEL FLOW
2
5
3
6
--- 1 lL.: ~ ~~JJ B38442-2Xl
9
8
10
11
12
FUEL SYSTEM SCHEMATIC 1. Fuel tank. 2. Fuel return line. 3. Priming pump. 4. Fuel injection nozzle. 5. Fuel injection line. 6. Fuel injection pump. 7. Primary tuellilter. 8. Check valve. 9. Fuel transler pump. 10. Secondary fuel filter. 11. Constant bleed orifice. 12. Fuel injection pump housing.
Fuel is pulled from fuel tank (1) through primary fuel filter (7) and check valves (8) by fuel transfer pump (9). From the fuel transfer pump the fuel is pushed through secondary fuel filter (10) and to the fuel manifold in fuel injection pump housing (12). The pumping spring in the fuel transfer pump keeps the fuel pressure in the system at 170 to 290 kPa (25 to 42 psi). Constan't bleed orifice (11) lets a constant flow of fuel go thorugh fuel return line (2) back to fuel tank (1). This helps keep the fuel cool and free of air. Fuel injection pump (6) gets fuel from the fuel manifold and pushes fuel at very high pressure through fuel line (5) to fuel injection nozzle (4). The fuel injection nozzle has very small holes in the tip that change the flow of fuel to a very fine spray that gives good fuel combustion in the cylinder.
FUEL INJECTION PUMP The fuel injection pump increases the pressure of the fuel and sends an exact amount of fuel to the fuel injection nozzle. There is one fuel injection pump for each cylinder in the engine. The fuel injection pump is moved by cam (14) of the fuel pump camshaft. When the camshaft turns, the cam raises lifter (11) and pump plunger (6) to the top of the stroke. The pump plunger always makes a full stroke. As the camshaft turns farther. spring (8) returns the pump plunger and lifter to the bottom of the stroke.
5 ."
FUEL SYSTEM
SYSTEMS OPERATION
When the pump plunger is at the bottom of the stroke, fuel at transfer pump pressure goes into inlet passage (2), around pump barrel (4) and to bypass closed port (5). Fuel fills the area above the pump plunger. After the pump plunger begins the up stroke, fuel will be pushed out the bypass closed port until the top of the pump plunger closes the port. As the pump plunger travels farther up, the pressure of the fuel increases. At approximately 690 kPa (100 psi). check valve ( I) opens and lets fuel flow into the fuel injection line to the fuel injection nozzle. When the pump plunger travels farther up, scroll (9) uncovers spill port (10). The fuel above the pump plunger goes through slot (7), along the edge of scroll (9) and out spill port (10) back to fuel manifold (3). This is the end of the injection stroke. The pump plunger can have more travel up, but no more fuel will be sent to the fuel injection nozzle. 2
.M 4
3
I ..~
6
scroll (9) changes the distance the pump plunger pushes fuel between bypass closed port (5) and spill port (10) opening. The longer the distance from the top of the pump plunger to the point where scroll (9) uncovers spill port (10), the more fuel will be injected. To stop the engine, the pump plunger is rotated so that slot (7) on the pump plunger is in line with spill port (10). The fuel will now go out the spill port and not to the injection nozzle.
FUEL INJECTION NOZZLE The fuel injection nozzle goes through the cylinder head into the combustion chamber. The fuel injec tion pump sends fuel with high pressure to the fuel injection nozzle where the fuel is made into a fine spray for good combustion.
1\ F I
6
7
8 FUEL INJECTION
8
9
ID 12
13 A92938X1
FUEL INJECTION PUMP 1. Check valve. 2. Inlet passage. 3. Fuel manifold. 4. Pump barrel. 5. Bypass closed port. 6. Pump plunger. 7. Siol. 8. Spring. 9. Scroll. 10. Spill port. 11. Ufter. 12. Fuel rack. 13. Gear. 14. Cam.
When the pump plunger travels down and un covers bypass closed port (5), fuel begins to fill the area above the pump plunger again, and the pump is ready to begin another stroke. The amount of fuel the injection pump sends to the injection nozzle is changed by the rotation of the pump plunger. Gear (13) is attached to the pump plunger and is in mesh with fuel rack (12). The governor moves the fuel rack according to the fuel needs of the engine. When the governor moves the fuel rack, and the fuel rack turns the pump plunger,
6
5
B9219X1 ~OZZLE
1. Carbon dam. 2. Seal. 3. Spring. 4. Filler screen. 5. Inlet passage. 6. Orifice. 7. Valve. 8. Diameter. 9. Passage.
Seal (2) goes against the cylinder head and pre vents leakage of compression from the cylinder. Car bon dam (I) keeps carbon out of the bore in the cylinder head for the nozzle. Fuel with high pressure from the fuel injection pump goes into inlet passage (5). Fuel then goes through filter screen (4) and into passage (9) to the area below diameter (8) of valve (7). When the pres sure of the fuel that pushes against diameter (8) becomes greater than the force of spring (3), valve (7) lifts up. When valve (7) lifts, the tip of the valve comes off of the nozzle seat and the fuel will go through the nine 0.20 mm (.008 in.) orifices (6) into the combustion chamber. The injection of fuel continues until the pressure of fuel against diameter (8) becomes less than the force of spring (3). With less pressure against diameter (8), spring (3) pushes valve (7) against the nozzle seal and stops the flow of fuel to the combustion chamber.
FUEL SYSTEM
SYSTEMS OPERATION
The 8N7005 Fuel Injection N o:zzle ca n not be disassembled and no adjustments can be made.
FUEL TRANSFER PUMP (LATER) The fuel transfer pump is a piston pump that is moved by a cam (eccentric) on the camshaft for the fuel injection pump The transfer pump is located on the bottom side or the fuel injection pump housing. B50041X1
is pushed thru the outlet check valve (3) and out pump outlet port (8). Fuel also moves thru pump in let port (6) and in let check valve (7) to fill the area below piston (2). The pump is now ready to start a new cycle. B50042X 1
3
3
2
4
~>I t'r/~ ~
4
5
8 FUEL TRANSFER PUMP (START OF UP STROKE) (ARROWS INDICATE FUEL FLOW DIRECTION)
1. Push rod. 2. Piston. 3. OUllet check valve. 4. Pumping check valve. 5. Pumping spring. 6. Pump inlet port. 7. Inlet check valve. B. Pump out lei port.
5
6
7
B
FUEL TRANSFER PUMP (START OF DOWN STROKE) (ARROWS INDICATE FUEL FLOW DIRECTION)
1. Push rod. 2. Piston. 3. Outlet check valve. 4. Pumping check valve. 5. Pumping spring. 6. Pump inlet port. 7. Inlel check valve. B. Pump outlet port.
When the fuel injection pump camshaft turns. the cam moves push rod (1) and piston (2) down. As the piston moves down, in let check valve (7) and outlet check valve (3) close. Pumping check valve (4) opens and allows the fuel below the piston to move into the area above the piston. Pumping spring (5) is com pressed as the piston is pushed down by push rod (1 ). As the fuel injection pump camshaft continues to turn, the cam no longer puts force on push rod (1 ). Pumping spring (5) now moves piston (2) up. This causes pum ping check valve (4) to close. Inlet check val ve (7) and outlet check valve (3) will open. As the piston moves up, the fuel in the area above the piston
FUEL TRANSFER PUMP (EARLIER) The fuel transfer pump is a two-piston pump that is moved by a cam (eccentric) on the camshaft for the fuel injection pump. The transfer pump is located on the right side of the fuel injection pump housing. When the camshaft turns, the cam lifts push rod (10) up. The push rod lifts luge piston (9), push plate (6) and small piston (3). As the pistons move up, inlet check valve (5) and outlet check valve (8) close. Pumping check valve (7) in the large piston opens and fuel goes through the holes in the bottom of the large piston and fills the passages and chamber between the bottom of the farge piston and outlet check valve (8). As small piston (3) moves up, the pressure of the fuel above the piston increases and flows out of the pump through outlet (4). As the camshaft continues to turn, the cam lowers push rod (l0) down. Pumping spring (2) pushes small piston (3), push plate (6) and large piston (9) down. When the piston moves down, inlet check valve (5) and outlet check valve (8) open. Pumping check
7
SYSTEMS OPERATION
FUEL SYSTEM
valve (7) in the large piston closes and the pressure of the fuel below the check valve increases. Fuel now flows through the outlet check valve. A part of the fuel goes through outlet (4) and the remainder goes to the area above small piston (3). 2
3
5
As the large piston moves down, fuel from the fuel tank is pulled through inlet check valve (5) into the area between the large and small piston. The pump is now ready to start a new cycle.
4
Bypass valve (I) controls the outlet pressure of the fuel. If the fuel pressure goes beyond 170 to 280 kPa (25 to 40 psi), the bypass valve opens and fuel flows to the inlet of the pump.
6
OIL FLOW FOR FUEL PUMP AND GOVERNOR Oil from the side of the cylinder block goes to support (9) and into the bottom of front governor housing (4). The flow of oil now goes in three differ en t directions.
1
l5lINLET FUEL
§ PRESSURE FUEL
9
10
B9213Xl
FUEl TRANSFER PUMP SCHEMATIC (UP STROKE)
1. Bypass valve. 2. Pumping spring. 3. Small piston. 4. Outlet. 5. Inlet check valve. 6. Push plate. 7. Pumping check valve. 8. Outlet check valve. 9. Large piston. 10. Push rod.
2
3
4
6
5
1
A part of the oil goes to the rear camshaft bearing in fuel pump housing (5). The bearing has a groove around the inside diameter. Oil goes through the groove and into the oil passage in the bearing surface (journal) of camshaft (7). A drilled passage through the center of the camshaft gives oil to the frvnt camshaft bearing and to the thrust face of the cam shaft drive gear. Drain hole (6) in the front of fuel pump housing (5) keeps the level of the oil in the housing even with the center of the camshaft. The oil returns to the oil pan through the timing gear housing. Oi I also goes from the bottom of the front governor
housing through a passage to the fuel pump housing
and to governor servo (2). The governor servo gives
hydraulic assistance to move the fuel rack.
~-~--
The remainder of the oil goes through passages
to the rear of rear governor housing (3), through air
fuel ratio control (1) and back into another passage
in the rear governor housing. Engines that do not
have an air fuel ratio control have a cover with an
oil passage to complete the oil flow. Now the oil goes
into the compartment for the governor controls.
Drain hole (8) keeps the oil at the correct level. The
oil in this compartment is used for lubrication of
the governor control components and the oil is the
supply for the dashpot.
8
The internal parts of the governor are lubricated
by oil leakage from the servo and the oil is thrown by
parts in rotation. The flyweight carrier thrust bear
ing gets oil from the passage at the rear of the
camshaft.
rn INLET FUEL Iii PRESSURE FUEL
9 B9214X1
FUEL TRANSFER PUMP SCHEMATIC (DOWN STROKE)
1. Bypass valve. 2. Pumping spring. 3. Small piston. 4. Outlet. 5. Inlet check valve. 6. Push plate. 7. Pumping check valve. 8. Outlet check valve. 9. Large piston. 10. Push rod.
8
10
Oil from the governor returns to the oil pan
through a hole in the bottom of the front governor
housing and through passages in the support and
cylinder block.
.;/
SYSTEMS OPERATION
FUEL SYSTEM
2
5
4
I
,I
~ PRESSURE OIL
9
OASHPOT OIL
\ 825650Xl
FUEL PUMP AND GOVERNOR 1. Air fuel ratio control. 2. Servo. 3. Rear governor housing. 4. Front governor housing. 5. Fuel pump housing. 6. Drain hole. 7. Camshaft. 8. Drain hole. 9. Support.
GOVERNOR The governor controls the amount of fuel needed by the engine to maintain a desired rpm. The governor flyweights (8) are driven directly by the fuel pump camshaft. Riser (l0) is moved by flyweights (8) and governor spring (l). Lever (7) connects the riser with sleeve (2) which is fastened to valve (3). Valve (3) is a part of governor servo (5) and moves piston (4) and fuel rack (6). The fuel rack moves toward the front of the fuel pump housing (to the right in the illustration) when moved in the FU EL OFF direction. The force of governor spring (I) always pushes to give more fuel to the engine. The centrifugal (rotating) force of flyweights (8) always push to get a reduction of fuel to the engine. When these two forces are in balance (equal), the engine runs at a constant rpm.
When the engine is started and the governor is at the low idle position, over fueling spring (9) moves the riser forward and gives an extra amount of fuel to the engine. When the engine has started and begins to run, the flyweight force becomes greater than the force of the over fueling spring. The riser moves to the rear and reduces the amoun~ of fuel to the low idle requirement of the engine. When the governor control lever is moved to the high idle position, governor spring (I) is put in compression and pushes riser (10) toward the flyweights. When the riser moves forward, lever (7) moves sleeve (2) and valve (3) toward the rear. Valve (3) stops oil flow through governor servo (5) and the oil pressure moves piston (4) and the fuel rack to the rear. This increases the amount of fuel to the engine. As engine speed increases, the flyweight force increases and moves the riser toward the governor spring. When the riser moves to the rear, lever (7) moves sleeve (2) and valve (3) 9
SYSTEMS OPERATION
FUEL SYSTEM
forward. Valve (3) now directs oil pressure to the rear of piston (4) and moves the piston and fuel rack for ward. This decreases the amount of fuel to the engine.
Governor Servo The governor servo gives hydraulic assistance to the mechanical governor force to move the fuel rack. The govemor servo has cylinder (3), cylinder sleeve (4), piston (2) and val ve (I).
~
}
11
GOVERNOR SERVO (Fuel on position)
89136-Jx3
GOVERNOR 1. Governor spring. 2. Sleeve. 3. Valve. 4. Piston. 5. Gov
ernor servo. 6. Fuel rack. 7. Lever. 8. Flyweights. 9. Over
fueling spring. 10. Riser. 11. Spring seat. 12. Stop
bolt. 13. Torque spring. 14. Power setting screw. 15. Tor
que rise selting screw. 16. Stop collar. 17. Stop bar. 18.
Load stop bar.
When the tlyweight force and the governor spring force become equal, the engine speed is constant and the engine runs 8t high idle rpm. High idle rpm is adjusted by the high idle adjustment screw. The adjustment screw 1imits the amount of compression of the governor spnng. With the engine at high idle, when the load is increased, engine speed will decrease. Flyweights (8) move in and governor spring (1) pushes riser (10) forward and increases the amount of fuel to the engine. As the load is increased more, governor spring (1) pushes riser (10) farther forward. Spring seat (11) pulls on stop bolt ( 12). Stop collar ( 16) on the opposite end has power setting screw (14) and (on engines so equipped) torque rise setting screw (15) that controls the maximum amount of fuel rack travel. The power setting screw moves forward and makes contact with load stop bar (18) or torque spring (13). This is the balance point. For engines with a torque spring, if more load is added to the engine, engine speed will decrease and push riser (10) forward more. This will cause power setting screw (14) to bend (deflect) torque spring (13) until torque rise screw (15) makes contact with stop bar (17). This is the point of maximum fuel to the engine.
10
B9220X1
D
B
1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5.
Fuel rack. A. Oil inlet. B. Oil outlet. C. Oil passage. D. Oil
passage.
When the governor moves in the FUEL ON direc tion, valve (1) moves to the left. The valve opens oil outlet (B) and closes oil passage (D). Pressure oil from from oil inlet (A) pushes piston (2) and fuel rack (5) to the left. Oil behind the piston goes through oil passage (C), along valve (l) and out oil outlet (B).
A
2
4
5
a LOW PRESSURE OIL B9222X1
GOVERNOR SERVO (Balanced position) 1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5. Fuel rack. A. Oil inlet. B. Oil outlet. C. Oil passage. D. Oil passage.
_lo'
SYSTEMS OPERATION
FUEL SYSTEM
4
When the governor spring and flyweight forces are balanced and the engine speed is constant, valve (1) stops moving. Pressure oil from oil inlet (A) pushes piston (2) until oil passages (C and D) are opened. Oil now flows through oil passage (D) along valve (1) and out through oil outlet (B). With no oil pressure on the piston, the piston and fuel rack (5) stop moving.
B92:24-1Xl
DASH POT
(Governor Moving to Fuel On)
1. Cylinder. 2. Piston. 3. Dashpot spring. 4. Spring seat. 5. Needle valve. 6. Check valve. 7. Oil reservoir.
GOVERNOR SERVO (Fuel Off Position) 1. Valve. 2. Piston. 3. Cylinder. 4. Cylinder sleeve. 5. Fuel rack. A. Oil inlet. B. Oil outlel. C. Oil passage. D. Oil oassaae.
When the governor moves in the FUEL OFF dir ection, valve (1) moves to the right. The valve closes oil outlet (B) and opens oil passage (D). Pressure oil from oil inlet (A) is now on both sides of piston (2). The area of the piston is greater on the left side than on the right side of the piston. The force of the oil is also greater on the left side of the piston and moves the piston and fuel rack (5) to the right. Dashpot
The dashpot helps give the governor better speed control when there are sudden speed and load changes. The dashpot has cylinder (1), piston (2), dashpot spring (3), needl~ valve (5) and check valve (6). Piston (2) and spring seat (4) are fastened to dashpot spring (3). When the governor moves toward FUEL ON, spring seat (4) and piston (2) move to the right. This movement pulls oil from oil reservoir (7) through check valve (6) and into cylinder (1).
1 DASHPOT
(Governor Moving to Fuel Off)
89224Xl
1. Cylinder. 2. Piston. 3. Dashpot spring. 4. Spring seat. 5. Needle valve. 6. Check valve. 7. Oil reservoir.
When the governor moves toward spring seat (4) and piston (2) move to movement pushes oil out of cylinder needle valve (5) and into oil reservoir
FUEL OFF, the left. This (1), through (7).
If the governor movement is slow, the oil gives no restriction to the movement of the piston and spring seat. If the governor movement is fast in the FUEL OFF direction, the needle valve gives a restriction to the oil and the piston and spring seat will move slowly.
11
SYSTEMS OPERATION
FUEL SYSTEM
AIR FUEL RATIO CONTROL 3 4
2
6
5
III
DRAIN OIL
1m FLOWING
11
10
9
8
1
B31943·2X1
OIL
AIR FUEL RATIO CONTROL (Engine Stopped) 1. Inlel air chamber. 2. Diaphragm assembly. 3. Internal valve. 4. Oil drain passage. 5. Oil inlet. 6. Stem. 7. Spring. Piston. 9. Oil passage. 10. Oil chamber. 11. lever.
a.
2
6
5
4
3
)
§INLET MAN. PRESSURE ODRAIN OIL ~FLOWING OIL
B3194J-1Xl
1
B
9
10
11
AIR FUEL RATIO CONTROL (Increase in Inlet Air Pressure) 1. Inlet air chamber. 2. Diaphragm assembly. 3_ Internal valve. Piston. 9. Oil passage. 10. Oil chamber. 11. lever.
4. Oil drain passage. 5. Oil inlet. 6. Stem. 7. Spring.
a.
'<~
12
.
-)
FUEL SYSTEM
SYSTEMS OPERATION
The air fuel ratio control limits the amount of fuel to the cylinders during an increase of engine speed (acceleration) to reduce exhaust smoke. ~,
Stem (6) moves lever (11) which will restrict the movement of the fuel rack in the FUEL ON direc tion only. With the engine stopped, stem (6) is in the fully extended position. The movement of the fuel rack a nd lever (11) is not restricted by stem (6). This gives maximum fuel to the engine for easier starts. After the engine is started, engine oil flows through oil inlet (5) into pressure oil chamber (10). From oil chamber (10) oil flows through oil pas sage (9) into internal valve (3) and out oil drain passages in stem (6). Stem (6) will not move until inlet manifold pres sure increases enough to move internal valve (3). A line connects the inlet manifold with inlet air chamber (I) of the air fuel ratio control. When inlet manifold pressure increases, it causes diaphragm assembly (2) to move towards the right. This also causes internal valve (3) to move to the right. When internal valve (3) moves to the right, it closes oil passage (9).
When oil passage (9) is closed, oil pressure in creases in oil chamber (10). Oil pressure moves piston (8) and stem (6) to the left and into the operating position. The air fuel ratio control will remain in the operating position until the engine is shut off. When the governor control is moved to increase fuel to the engine, stem (6) limits the movement of lever (II) in the FUEL ON direction. The oil in oil chamber (10) acts as a restriction to the move ment of stem (6) until inlet air pressure increases. As the inlet air pressure increases, diaphragm assembly (2) and internal valve (3) move to the right. The internal valve opens oil passage (9), and oil in oil chamber (10) goes to oil drain pas sage (4). With the oil pressure reduced behind piston (8), spring (7) moves the piston and stem (6) to the right. Piston and stem (8 and 6) will move until oil passage (9) is closed by internal valve (3). Lever (II) can now move to let the fuel rack go to the full fuel position. The air fuel ratio control is designed to restrict the fuel until the air pressure in the inlet manifold is high enough for complete combustion. It prevents large amounts of exhaust smoke caused by an air-fuel mixture with too much fuel.
5
[t':l DRAIN OIL STOPPED OIL
B31943X1
1
B
9
10
11
AIR FUEL RATIO CONTROL (Ready for Operation) 1. Inlet air chamber. 2. Diaphragm assembly. 3. Internal valve. 4. Oil drain passage. 5. Oil inlet. 6. Stem. 7. Spring. B. Piston. 9. Oil passage. 10. Oil chamber. 11. Lever.
13
FUEL SYSTEM
TESTING AND ADJUSTING
FUEL SYSTEM
,'~
Either too much fuel or not enough fuel for com bustion can be the cause of a problem in the fuel system. Many times work is done on the fuel system when the problem is reaJly with some other part of the engine. The source of the problem is difficult to find, especially when smoke comes from the exhaust. Smoke that comes from the exhaust can be caused by a bad fuel injection valve, but it can also be caused by one or more of the reasons that follow:
I
(
;
a Not enough air' for good combustion. b. An overload at high altitude. c. Oil leakage into combustion chamber. d. Not enough compression. e. Fuel injection timing retarded.
FUEL SYSTEM INSPECTION
~~
To check for low fuel pressure, remove the Ys" Pipe Plug from the fuel filter base. Connect the 8M2743 Gauge from the 5P6225 Hydraulic Test Box to the hole where the plug was removed. Run the engine at high idle and check the fuel pressure reading. The fuel pressure must be at least 105 kPa (15 psi).
A problem with the components that send fuel to the engine can cause low fuel pressure. This can decrease engine performance. I. Check the fuel level in the fuel tank. Look at the cap for the fuel tank to make sure the vent is not filled with. dirt. 2. Check the fuel lines for fuel leakage. Be sure the fuel supply line does not have a restriction or a bad bend. 3. Install a new fuel filter. Clean the primary fuel filter.
4. Remove any air that may be in the fuel system. If there is air in the fuel system, use the priming pump and open the drain valve on the fuel injec tion pump housing until fuel without air comes from the drain line.
NOTICE When fuel injection lines are loosened or tight ened on the fuel injection nozzles, two wrenches must be used. The nozzle must be held with a wrench or damage to the nozzle can result. To remove air from the fuel injection lines, loosen the fuel line nuts on the fuel injection nozzles 1/2 turn. Move the governor lever to the low idle position. Crank engine with the starter motor until fuel with out air comes from the fuel line connections. Tighten the fuel line nuts. NOTE: The fuel priming pump will not give enough pressure to push fuel through the reverse flow check valves in the fuel injection pumps.
CHECKING ENGINE CYLINDERS
SEPARATELY
An easy check can be made to find the cylinder that runs rough (misfires) and causes black smoke to come out of the exhaust pipe. Run the engine at the speed that is the roughest. Loosen the fuel line nut at a fuel injection pump. This will stop the /low of fuel to that cylinder. Do this for each cylinder until a loosened fuel line is found that makes no difference in engine performance. Be sure to tighten each fuel line nut after the test before the next fuel line nut is loosened. Check each cylinder by this method. When a cylinder is found where the loosened fuel line nut does not make a difference in engine performance, test the injection pump and fuel injection nozzle for that cylinder. Temperature of an exhaust manifold port, when a engine runs at low idle speed, can also be an indica tion of the condition of a fuel injection nozzle. Low
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35
FUEL SYSTEM
temperature at an exhaust manifold port is an indica tion of no fuel to the cylinder. This can possibly be an indication of a nozzle with a defect. Extra high tem perature at an exhaust manifold port can be an indi cation of too much fuel to the cylinder, also caused by a nozzle with a defect.
TESTING AND ADJUSTING ;'"
~,,--
,
r
The most common defects found with the fuel injeclion nozzles are: 1. Carbon on tip of the nozzle or in the nozzle ori ficc. 2. Orifice wear. EXTRA VALVE L. Gauge protector valve (must be in open position at all
times).
NOTICE Do not test nozzles unless you have the correct service tools. TESTING 8N7005 & 8N7001 FUEL
INJECTION NOZZLES
Tools Needed:
*5P4150 Nozzle Testing Group.
5P7448 Adapter.
8S2270 Fuel Collector.
FT1384 Extension.
8S2245 Cleaning Tool Group.
8S2258 Brass Wire Brush. 6V4979 Carbon Seal Installation Tool.
1F1153 Needle Nose Pliers.
5V2170 Tube Assembly.
7/64" Hex Wrench.
*Special Instruction Form No. SEHS7292.
NOTICE Be sure to use clean SAE J967 Calibration Fluid when tests are made. Dirty test fluid will dam age components of fuel injection nozzles. The temperature of the test fluid must be 1B to 24° C (65 to 75° F) for good test results.
'----'"
Order calibration fluid by part number, in the quantities needed, according to the information that follows: 6V6068 Calibration Fluid, 18.9 liter (5 U.S. gal.) 6V6067 Calibration Fluid, 208.2 liter (55 U.S. gal.)
~
5P4150 NOZZLE TESTING GROUP 1. BN7005 Nonie Assembly. A. 5P7448 Adapter. B. 5P4146 Gauge, 0 to 6900 kPa (0 to 1000 psi). C.6V2170 Tube Assembly. D. 2P2324 Gauge, 0 to 34500 kPa (0 to 5000 psi). E. Gauge protector valve ior 2P2324 Gauge. F. FT1384 Extension. G. Gauge protector valve for 5P4146 Gauge. H. On-off valve. J. 852270 Fuel Collector. K. Pump isolator valve.
The 8N7005 & 8N700 I Fuel Injection Nozzles are not to be disassembled for cleaning or adjust ment. Do the tests that follow to determine if the nozzle performance is acceptable. \,--""
36
TESTING AND ADJUSTING
FUEL SYSTEM
I. Remove fuel filter base (1) and the fuel line from the fuel filter base to the fuel transfer pump. "---
-
,:B74916Xl
!
2. Remove bolts (2) and timing pin cover (3) from the fuel injection pump housing.
.l
J TIMING PIN INSTALLED 4. Timing pin.
7. Install 8S2244 Extractor (5) on the threads of the injection pump. Carefully pull the pump straight up out of the bore. FUEL INJECTION PUMP HOUSING
1. Fuel filter base.
''-'
Be careful when an injection pump is disassem bled. Do not damage the surface on the plunger. The plunger and barrel are made as a set. Do not put the plunger of one pump in the barrel of another pump. If one part is worn, install a complete new pump assembly. Be careful when the plunger is put into the bore of the barrel. When injection pump and spacers are removed from the fuel injection pump housing, keep the parts together so they can be installed in the same location in the housing. Installation of Fuel Injection Pumps NOTICE The fuel rack MUST BE IN THE CENTER POSI TION before the correct installation of an in jection pump is possible.
FUEL INJECTION PUMP HOUSING 2. Bolts. 3. Timing pin cover.
3. Move the governor lever to the FUEL OFF position and install timing pin (4) in the rack centering hole as shown. 4. With the timing pin in position, move the gov ernor lever to the high idle position. The fuel rack will move until the edge of the groove in the rack makes contact with the timing pin. The fuel rack is now in the center position. Fasten the governor lever in the HIGH IDLE position. 5. Remove the fuel injection line from the fuel injection pump.
,-.
6. Put the 8S4613 Wrench into spline of bushing that holds the fuel injection pump in the hous ing. Remove the bushing.
1. Put the fuel rack in the center position. Make reference to Removal of Fuel Injection Pumps. 2. Put the 8S2244 Extractor on the threads of the fuel injection pump. 3. Make sure the lifter for the pump to be installed is at the bottom of its travel. 4. Put the groove of barrel (6) in alignment with the middle (fourth) tooth of gear segment (7). 5. Look into the bore for the fuel injection pump and locate both dowels. There is a dowel in the lifter and a dowel in the opposite side of the bore in the fuel injection pump housing. Put the groove in the pump barrel in alignment with the large dowel in the pump housing and put the slot (groove) on the opposite side of the gear teeth on the sector gear in alignment with the small dowel in the lifter. Install the fuel injec tion pump straight down into the bore. 41
FUEL SYSTEM
"
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I. II. Ill, IV. V.
TESTING AND ADJUSTING
Valve Opening Pressure Test. Flush the Nozzle.
Tip Leakage Test.
Orifice Restriction Test. Bleedscrew Leakage Test.
M
Nozzle Preparation for Test
\; f
Before fuel injection nozzle (I) can be tested, all loose carbon around the tip of the nozzle must be removed with the 8S2258 Brass Wire Brush (M).
A756J8Xl
852245 CLEANING KIT M. 852258 Brass Wire Brush. N. 6V4979 Carbon Seal Tool. p, 852250 Nozzle Holding Tool.
B3496Xt
B3475X1 '--
REMOVING CARBON DAM
1. Fuel injection nozzle, 2. Carbon dam. 3. Seal. Remove carbon dam (2) with needle nose pliers and remove seal (3) from the nozzle,
BN7005 FUEL INJECTION NOZZLE 4. Bleed screw and seal.
Remove bleed screw and seal (4 ) from the nozzle.
NOTICE Do not use a steel brush or a wire wheel to clean the nozzle body or the nozzle tip. Use of these tools can cause a small reduction of orifice size, and this will cause a large reduction in engine horsepower. Too much use of the 852258 Brass Wire Brush will also remove the coating that is on the nozzle for protection. Clean the groove for carbon seal darn (2) and the body of the nozzle below the groove with the 8S2258 Brass Wire brush (M). Remove the carbon, but be sure not to use the brush enough to cause damage to the body of the nozzle.
1
NOTE: A change in color in the area below the groove is normal and does not effect the body of the nozzle.
I
NOTE: The bleed screw and seal must be removed for all tests except test V; Bleed Screw Leakage Test.
I. Valve Opening Pressure Test (VOP)
1. Install 6V2I70 Tube Assembly (C) to the tester. 2. Install 8N7005 or 8N700 I FuelInjection Nozzle with 5P7448 Adapter (A) on tube assembly (6). Position the bleed screw hole toward the tester and in line with 6V2170 Tube Assembly (C). This will make the fuel spray pattern hori zontal. Be sure the nozzle tip is down and ex tends into FTl384 Extension (F) and 8S2270 Fuel Collector (J).
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37
----I
FUEL SYSTEM
TESTING AND ADJUSTING
A WARNING When fuel injection nozzles are tested, be sure to wear eye protection. Test fluid comes from the orifices in the nozzle tip with high pressure. The test fluid can pierce (go thru) the skin and cause serious injury to the operator. Keep the tip of the nozzle pointed away from the opera tor and into the 8S2270 Fuel Collector and FT1384 Extension.
VALVE OPENING PRESSURE (VOPl SPECIFICATIONS 8300 to 16 200 kPa (1200 to 2350 psi)
II. Flush the Nozzle
~
I. Close gauge protector valve (E). Close on-off
valve (H). Open pump isolator valve (G).
NOTE: Make sure nozzle extends inside and below the top of FTl384 Extension (F). 2. Operate the pump rapidly for three full strokes.
III. Tip Leakage Test
I. Remove all fuel from the nozzle tip and body
with a clean cloth.
B3476Xl
NOZZLE READY FOR TEST E. Gauge protector valve. H. On-off valve. K. Pump isola lor valve.
2. Put a clean cloth around the body of the nozzle to
take in any leakage from the bleed screw hole
and prevent any fuel leakage to drain down to
the tip of the nozzle.
NOTICE Put a shop towel around the upper part of the nozzle to take in any fuel leakage.
3. Close on-off valve (H). Open pump isolator valve (K). 4. Open gauge protector valve (E). Operate the pump to make a slow increase in pressure until the valve in the fuel injection nozzle just starts to open. Read the maximum gauge pressure at the instant fluid flows from the tip. NOTE: It is possible for the pressure reading of the gauge to go down fast if the valve makes a noise (chatters) when it opens. It is also possible for the pressure reading of the gauge to be almost constant when the valve in the fuel injection nozzle opens. NOTE: The valve in the fuel injection nozzle can be good and still not make a noise (chatter), or not have a very fine va por (spray) from the orifices in the tip of the fuel injection nozzle during Step 4.
If the opening pressure is not within specifications, do not use the fuel injection nozzle again.
38
B3476Xl
NOZZLE READY FOR TEST E. Gauge protector valve. H. On-off valve. K. Pump isola
tor valve.
3. Open gauge protector valve (E). Close on-off valve (H). Open pump isolator valve (K).
t
4. Make and hold for 15 seconds a pressure of 1380 kPa (200 psi) less than the opening pressure measured in YOP Test I and make a note of the number of drops that fall. TIP LEAKAGE SPECIFICATION No more than 5 drops can fall in 15 seconds.
".....-/
TESTING AND ADJUSTING
FUEL SYSTEM
5. If the nozzle is not within specifications. DO NOT USE THE NOZZLE. '"'-.-"
IV. Orifice Restriction Test I. Close gauge protector valve (E) and on-off valve (H). Open pump isolator valve (K).
2. Point the tip of the fuel in-jection nozzle into the 8S2270 Fuel Collector and FTl384 Extension. Be sure the bleed screw hole is positioned toward the tester and is in line with 6V2170 Tube As sembly (C). This will make the fuel injection nozzle be 15° from vertical and the spray pat tern will be horizontal.
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r
B9146Xl TYPICAL DISCHARGE PATTERN WITH VERTICAL
DISTORTION
(REPLACEMENT NECESSARY)
V. Bleed Screw Leakage Test
3. Make a slow increase in pressure and look at the orifice discharge pattern (shape of discharge) when fluid begins to flow through the fuel injec tion nozzle. The discharge must be the same through all nine orifices. Any change either ver tically or horizontally, is an indication of a bad nozzle.
I. Install bleed screw and seal (4) in fuel injection nozzle. Tighten the bleed screw to a torque of 1.8 ± 0.2 N-m (16 ± 2 lb. in.).
NOTICE Do not tighten the bleed screw more than the torque shown. The bleed screw or seal can be damaged. 2. Put the tip of the fuel injection nozzle down inside the 8S2270 Fuel Collector and FT1384 Extension.
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3. Close on-off valve (H). Open gauge protector valve (E) and pump isolator valve (K).
B9143X1 GOOD NOZZLE (USE AGAIN)
4. Pump the tester until fuel injection nozzle is full of fluid and the pressure on the gauge is 27 500 kPa (4000 psi). NOTE: 15 or 20 strokes of the pump can be neces sary for the pressure to get to 27 500 kPa (4000 psi).
B9144X1
BLEED SCREW LEAKAGE SPECIFICATION There must be no leakage between the bleed screw and the body of the fuel injection nozzle.
TYPICAL DISCHARGE PATTERN FOR ORIFICE
WITH A RESTRICTION
(REPLACEMENT NECESSARY)
5. If there is leakage, replace the 8N4174 Seal. Inspect the washer face of the bolt for damage, replace if needed. Test the nozzle again. If there is still leakage, the fuel injection nozzle must be replaced. B9145X1
.----...
.
,
TYPICAL DISCHARGE PA TTERN WITH HORIZONTAL DISTORTION (REPLACEMENT NECESSARY)
6. If no fuel leakage is found, the fuel injection nozzle is acceptable. Put a new seal (3) on the nozzle. Install a new carbon dam (2) in nozzle groove with 6V4979 Carbon Seal Tool (N).
39
FUEL SYSTEM
TESTING AND ADJUSTING
When there is too much wear on the fuel injection pump plunger, the lifter may also be worn and there will not be good contact between the two parts. To stop fast wear on the end of a new plunger, install new lifters in the place of the lifters that have wear.
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i
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B3495X2' B9229X1
B
A
c
INSTALLING CARBON DAM
2. Carbon dam. 3. Seal.
N. 6V4979 Carbon Seal Tool.
FUEL INJECTION LINES
Fuel from the fuel injection pumps goes to the fuel injection nozzles through the fuel injection lines. When fuel injection lines are disconnected or re moved, always put caps or plugs on the ends to keep dirt out of the lines. When fuel injection lines are installed, be sure all clamps and dampers are in sta lled in their origi nal loca tion. The nuts that hold a fuel injection line to an injec tion nozzle and injection pump must be tightened to the correct torque. If the nut is loose, fuel will leak from the connection. If the nut is tightened too tight, the inside diameter of the line will become smaller and cause a restriction to the flow of fuel in the line. Use a torque wrench and a 5P144 Fuel Line Socket to tighten the fuel injection line nuts to 40 ± 7 N·m (30 ± 5 lb. ft.).
WEAR BETWEEN LIFTER AND PLUNGER Fig. A. IIlustrales the contact surfaces 01 a new pump plunger and a new lifter. In Fig. B the pump plunger and lifler have worn considerably. Fig. C shows how the flat end of a new plunger makes poor contact with a worn liller, resulting in rapid wear to both parts.
An injection pump can have a good fuel flow com ing from it but not be a good pump because of slow timing that is caused by wear on the bottom end of the plunger. When making a test on a pump that has been used for a long time, use a micrometer and measure the length of the plunger. If the length of the plunger is shorter than the minimum length (worn) dimension given in the chart, install a new pump. ~
FUEL PUMP PLUNGER Length (new) .. 73.886 ± 0.013 mm (2.9089 ± .0005 in.)
Minimum length (worn) 73.873 mm (2.9084 in.)
Look for wear at the top part of the plunger. Check the opera tion of the plunger according to the instruc tions for the Fuel Injection Test Bench.
A WARNING Fuel injection lines which are bent, damaged or rubbing can leak and cause a fire. Replace any lines which have damage or leaks that can not be corrected when tightened to the correct torque.
REMOVAL AND INSTALLATION OF FUEL INJECTION PUMPS Tools Needed: 854613 Wrench. 852244 Extractor. 6V4186 Timing Pin.
Removal of Fuel Injection Pumps CHECKING THE PLUNGER AND LIFTER OF AN ·INJECTION PUMP
NOTE: There are no different size spacers available to adjust the timing dimension of the fuel injection pumps. If the pump plunger or the lifter is worn, they must be replaced. Because there is no adjustment to the timing dimension possible, there is NO OFF' ENGINE LIFTER SETTING PROCEDURE.
40
NOTICE
j
Before any parts are removed from the fuel injection pump housing, thoroughly clean all dirt from the housing. Dirt that gets inside the pump housing will cause much damage.
NOTE: The fuel rack must be in the center position before the fuel injection pumps can be removed.
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TESTING AND ADJUSTING
FUEL SYSTEM
1. Remove fuel filter base (l) and the fuel line from the fuel filter base to the fuel transfer pump. .~
'"
B74916X1 ,
l'
2. Remove bolts (2) and timing pin cover (3) from the fuel injection pump housing.
~ TIMING PIN INSTALLED 4. Timing pin.
7. Install 8S2244 Extractor (5) on the threads of the injection pump. Careful1y pull the pump straight up out of the bore. FUEL INJECTiON PUMP HOUSING 1. Fuel filter base.
'"'
Be careful when an injection pump is disassem bled. Do not damage the surface on the plunger. The plunger and barrel are made as a set. Do not put the plunger of one pum p in the barrel of another pump. If one part is worn, install a complete new pump assembly. Be careful when the plunger is put into the bore of the barrel. When injection pump and spacers are removed from the fuel injection pump housing, keep the parts together so they can be installed in the same location in the housing. Installation of Fuel Injection Pumps NOTICE The fuel rack MUST BE IN THE CENTER POSI TION before the correct installation of an in jection pump is possible.
FUEL INJECTION PUMP HOUSING 2. Bolts. 3. Timing pin cover.
3. Move the governor lever to the FUEL OFF position and install timing pin (4) in the rack centering hole as shown. 4. With the timing pin in position, move the gov ernor lever to the high idle position. The fuel rack will move until the edge of the groove in the rack makes contact with the timing pin. The fuel rack is now in the center position. Fasten the governor lever in the HIGH IDLE position.
.'! ,. ,l
1
5. Remove the fuel injection line from the fuel injection pump. '--"
6. Put the 8S4613 Wrench into spline of bushing that hold s the fuel injection pump in the hous ing. Remove the bushing.
I. Put the fuel rack in the center position. Make reference to Removal of Fuel Injection Pumps. 2. Put the 8S2244 Extractor on the threads of the fuel injection pump. 3. Make sure the lifter for the pump to be installed is at the bottom of its travel. 4. Put the groove of barrel (6) in alignment with the middle (fourth) tooth of gear segment (7). 5. Look into the bore for the fuel injection pump and locate both dowels. There is a dowel in the lifter and a dowel in the opposite side of the bore in the fuel injection pump housing. Put the groove in the pump barrel in alignment with the la rge dowel in the pump housing and put the slot (groove) on the opposite side of the gear teeth on the sector gear in alignment with the small dowel in the lifter. Install the fuel injec tion pump straight d own into the bore. 41
FUEL SYSTEM
TESTING AND ADJUSTING
A
WARNING
Be careful when plate is put against air inlet opening. Due to excessive suction, the plate can be pulled quickly against air inlet open ing. To avoid crushed fingers, do not put fingers between plate and air inlet opening.
'--../
FUEL PUMP INSTALLATION 5. 8S2244 Extractor. 6. Groove of barrel. 7. Fourth tooth of gear segment.
6. Push down On extractor (5) (hand force only) and install a-ring and bushing that holds the injection pump in the pump housing. If the pump is in the correct position, the bushing will turn into the threads of the fuel injection housing with the fingers until it is even with the top of the housing. When the bushing is in stalled correctly, tighten the bushing to 160 ± 14 Nom (120 ± 10 Lb. ft.) NOTICE The bushing must be tightened to the correct torque. Damage to the housing will be the re sult if the bushing is too tight. If the bushing is not tight enough, the pump will have leakage. 7. Install the fuel injection line to the pump and tighten to 40 ± 7 Nom (30 ± 5 lb. ft.). 8. Remove timing pin (4) and install timing pin cover (3). NOTICE If one or more of the fuel injection pumps have been installed wrong, it is possible for the en gine to run out of control when started. When any of the fuel injection pumps have been re moved and installed, take the precautions (steps) that follow to stop the engine if it starts to overspeed (run out of control). a. (Engines without turbocharger). Remove the air cleaner. (Engines with turbocharger). Remove tube assembly and hose from the air inlet side of turbocharger. b. Set the governor at low idle.
STOPPING THE ENGINE (TYPICAL EXAMPLE)
c. Start the engine, and if engine starts to over speed (run out of control) put a steel plate over the air inlet to stop the engine.
~
FINDING TOP CENTER COMPRESSION POSITION FOR NO.1 PISTON Tools Needed: 5P7307 Engine Turning Tool Group. 3/8-16 NC Boll.
No. I piston at top center (TC) on the compres sion stroke is the starting point for all timing pro cedures.
1. Remove the valve cover. 2. Remove plug (1). NOTE: The engine is seen from the flywheel end when direction of crankshaft rotation is given. 3. Remove the starter motor and install 5P7307
Engine Turning Tool Group.
4. Turn the flywheel clockwise approximately 60°. ~
42
I
FUEL SYSTEM
TESTING AND ADJUSTING
CHECKING ENGINE TIMING WITH 6V3100 DIESEL ENGINE TIMING INDICATOR GROUP
~
Tools Needed: 6V3100 Diesel Engine Timing Indicator Group.
Special Instruction Form No. SEHS7742 is with the tool group and gives instructions for the test procedure. NOTICE
LOCATION OF PLUG
The engine must be stopped while the timing indicator is being connected.
1. Plug. ..=;
5. Now tUln the flywheel counterclockwise until a 3/8" 16 NC bolt (2) can be put through hole (3) and installed in the timing bolt hole in the flywheel.
~
6. Look at the valves for No. I cylinder (the two valves at the front of the engine). The intake valve and exhaust valve for No. J cylinder must be closed. If they are closed, you will be able to move both rocker arms up and down by hand. 7. If the intake valve and exhaust valve for No. I cylinder are not closed, remove bolt (2). Turn the crankshaft counterclockwise 360° and in stall bolt (2). Both valves are now closed. This is top center (TC) compression position for No. 1 piston.
~w~ 6V3100 DIESEL ENGINE TIMING INDICATOR GROUP 1. Engine liming indicator. 2. TOC magnetic transducer. 3. Pipe adapter. 4. Injection transducer. 5. 5P7437
Adapter. 6. 5P7435 Tee Adapter. 7. 5P7436 Adapter.
1. Make reference to Operation Instructions in side the lid of the 6V3100 Diesel Engine Timing Indicator Group for complete instructions and calibration.
INSTALLING BOLT 2. Bolt.
3. Hole.
NOTE: If the flywheel bolt hole is turned beyond hole (3) and bolt (2) can not be installed, turn the flywheel clockwise approximately 60°. Then, turn it counterclockwise until bolt (2) can be installed. The reason for this step is to be sure the play is re moved from the timing gears when the engine is put on top center.
2. Lossen all fuel line clamps that hold No.1 fuel injection line and disconnect fuel injection line (8) for No. I cylinder at the fuel injection pump. Slide the nut up and out of the way. Put 5P7436 Adapter (7) in its place and turn adapter (7) onto the fuel pump bonnet until the top of the bonnet threads are approximately even with the bottom of the "window" in the adapter. 3. Put the 5P7435 Tee Adapter (6) on the Injection transducer (4) and put the end of the 5P7435 Tee Adapter (6) in the "window" of the 5P7436 Adapter (7). 4. Put fuel injection line (8) on top of 5P7435 Tee Adapter (6). Install 5P7437 Adapter (5) and tighten to 40 Nom (30 lb. ft.).
43
TIMING CHART 18 ± 1° ENGINE rpm
INDICATOR READING
1000 2100
17.B to 20.2° 18.9 to 21.3°
TIMING CHART 21 ± 1°
TRANSDUCER IN POSITION (TYPICAL EXAMPLE) 4. Injection transducer. cylinder.
8. Fuel injection line for No.1
5. Remove the plug from the flywheel housing. Install pipe adapter (3) into the hole the plug was removed from. Tighten only a small amount.
6. Push the TDC magnetic transducer (2) into the pipe adapter (3) until it makes contact with the flywheel. Pull it back out 1.6 mm (.06 in.) and lightly tighten the knurled locknut. 7. Connect the cables from the transducers to the Engine Timing Indicator. Make a calibration check of the indicator. For calibration pro cedure, make reference to Special Instruction Form No. SEHS7742.
8. Start the engine. Get the engine to operating temperature. With the engine at low idle, check engine timing. Increase engine speed and check timing at 2[00 rpm.
ENGINE rpm
INDICATOR READING
1000 2100
20.8 to 23.2° 21.9 to 24.3°
If the engine timing is not correct, make reference to CHECKING TIMING BY TIMING PIN METHOD for the procedure to change engine timing.
CHECKING TIMING BY TIMING PIN METHOD Tools Needed: 852264 Puller Group. 1B3680 Bolts (2) 3/8-24 NF, 95.3 mm (3.75 in.) long. 4B5271 Washer (2). 8B7560 Step Plate. ll138 Bolt 3/8-24 NF, 12.7 mm (.5 in.) tong. 6V4186 Timing Pin. 6V6175 Adapter.
l. Put No. I piston at top center on the com pression stroke. Make reference to LOCAT ING TOP CENTER COMPRESSION POSI TION FOR NO. 1 PISTON. Remove the timing bolt and rotate the crankshaft clock wise 30°.
2. Remove fuel line (1) and fuel filter base (2) and fuel filter from fuel injection pump hous mg. 3. Remove cover (3) from the side of the fuel in jection pump housing.
B21508X1
TRANSDUCER IN POSITION 2. TDC magnelic transducer.
The TIMING CHART gives the acceptable dy namic (engine in motion) timing range as read on the Timing Indicator Group. The TIMING CHARTS are for 3304 Engines with 18 ± I° and 21 ± 10 static (engine stopped) timing. 44
RIGHT SIDE OF ENGINE (TYPICAL EXAMPLE) 1. Fuel line. 2. Fuel filler base.
FUEL SYSTEM
TESTING AND ADJUSTING
in the timing hole in the nywheel, the timing of the fuel injection pump is correct. 6. If the timing bolt does not go into the timing hole in the flywheel, the timing is not correct. Do the steps that follow to adjust the fuel in jection pump timing. 7. Remove timing gear cover (5) from the timing gear housing.
\....
'" TIMING PIN COVER 3. Cover.
:A13949X3 TIMING GEAR FOR THE FUEL INJECTION PUMP
6. Bolt.
8. Loosen bolt (6) that holds the timing gear to the fuel pump camshaft. Turn bolt (6) out (counterclockwise) three turns.
. B31~56X1 TIMING PIN INSTALLED
4. 6V4186 Timing Pin.
4. Install 6\"4186 Timing Pin (4) in the fuel in jection pump housing as shown. Slowly rotate the crankshaft counterclockwise until timing pin (4) goes into the groove in the fuel pump camshaft. 5. Put the limi:1g bolt in the timing hole in the nywheel hOlJlsing. If the bolt can be installed
9. Install 8S2264 Puller Group and loosen the timing gear from the fuel pump camshaft. 10. Remove the timing bolt from the nywheel housing. Rotate the crankshaft clockwise 60° before top center No. I piston. lo1
II. Tighten bolt (6) fi nge I' tight. Be sure timing pin (4) is in the groove in the fuel pump cam shaft.
'" l~
PULLER INSTALLED FRONT OF ENGINE
5. Timing gear cover.
7.852264 Puller Group. 8. 8B7560 Step Plate. 9.183690 Boll '1."-24NF, 95.3 mm (3.75 in.) long. 10.485271 Wash er.
45
FUEL SYSTEM
TESTING AND ADJUSTING
GOVERNOR ADJUSTMENT FOR AIR FUEL RATIO CONTROL
12. Slowly rotate the crankshaft counterclock wise until the timing bolt can be installed in the flywheel.
Tools Needed:
6V4186 Timing Pin.
6V2106 Rack Adjustment Tool Group.
6V2017 Governor Adjusting Tool Assembly.
S1614 Bolt 1/4-20, 12.7 mm (.5 in.) long.
6V2031 Rack Position Indicator.
9S229 Contact Point, 9.7 mm (.38 in.) long.
5P4814 Collet.
6V3075 Dial Indicator.
6V7941 Compressor, Overtueling Spring.
The governor adjustment for the air fuel ratio control can be done with the fuel injection pump and governor on or off the engine. 'B38446Xt ADAPTER INSTAllED ON TIMING GEAR
11. 6V6175 Adapter.
13. Install 6V6I75 Adapter on the timing gear. Use two Ys"-24 NF bolts, 25.4 mm (1.0 in.) long to fasten the spanner to the puller holes in the timing gear.
NOTE: The air fuel ratio control is set to specific dimensions at the factory. If the control is dis assembled it must be set again on the 6V2029 Fixture Group before the governor adjustment is made. Make reference to Fuel Injection Test Bench Form No. SEHS7466 Section IV-Q for in structions for the use of 6V2029 Fixture Group.
r'
TIGHTENING TIMING GEAR BOLT (TYPICAL EXAMPLE)
I. Remove the fuel filter base and fuel line from the fuel injection pump housing and remove cover (1). " . .....,....." .....,.•-.. ~-.....
~
<-~~
FUEL INJECTION PUMP AND GOVERNOR
1. Cover.
2. Install 5P4814 Collet (2) on 6V2014 Bracket Assembly (3). 14. Hold a torque of 60 to 70 Nom (45 to 50 lb. f1.) on adapter (11) in a clockwise direction, and tighten bolt (6) that holds the timing gear to 270 ± 30 Nom (200 ± 20 lb. ft.). 15. Remove the timing bolt from the flywheel and timing pin (4) from the fuel pump camshaft. 16. Rotate the crankshaft counterclockwise two revolutions. If the timing bolt can be installed in the flywheel and the timing pin can be in stalled in the fuel pump camshaft, the timing is correct. 17. If either the timing pin or the timing bolt can not be installed, do Steps 8 througb 16 again. 46
3. Install the bracket assembly on the fuel pump housing. Lever (5) on the bracket assembly must be in slot (4) on the fuel rack. Push up on the bracket assembly while the bolts are tight ened. After the bracket assembly is tightened to the pump housing, shaft (6) must have axial (in and out) movement. If there is no axial move ment of shaft (6), check to be sure lever (5) is in the slot on the fuel rack and that the bracket assembly is installed correctly. Check to make sure that lever (5) is not bent. Lever (5) must be perpendicular (at right angle) to the mounting face of the bracket assembly.
FUEL SYSTEM
TESTING AND ADJUSTING
BRACKET ASSEMBLY INSTALLED
DIAL INDICATOR INSTALLED
2. 5P4814 Colle!. 3. Bracket assembly.
7. 6V3075 Dial Indicator.
GOVERNOR
a. Air fuel
COVER REMOVED
ratio control.
4. Slot on ruel rack.
B67313X1
REAR OF GOVERNOR HOUSING BRACKET ASSEMBLY
9. Plug.
5. Lever. 6. Shaft.
4. Put 9S229 Contact Point, 9.7 mm (.38 in.) long on 6Y3075 Dial Indicator (7) and install dial indicator in collet (2). 5. Remove air fuel ratio control (8) from the rear of the governor housing.
6. Remove plug (9) from the rear of the governor housing.
7. Move the governor control lever to the FUEL OFF position (rotate governor shaft clock wise). 8. Install 6Y4186 Timing Pin (10) in the hole in the bracket assembly. Push timing pin in until contact is made with the fuel rack. H old the timing pin gently against the fuel rack for Steps 9 and 10. If too much force is used to hold the timing pin the fuel rack can stick and cause an incorrect zero reading.
47
FUEl SYSTEM
TESTING AND ADJUSTING
II. With the hook still pulled toward the rear of the governor, loosen collet (2) and adjust the revolution counter on the dial indicator to zero. Tighten the collet just enough to hold the indicator in this position. Move the dial of the indicator to get alignment of the pointer and zero. 12. Remove timing pin (10).
TIMING PIN INSTALLED 10. 6V4186 Timing Pin.
9. Hold the governor control lever in the HIGH IDLE position (rotate governor shaft counter clockwise).
13. Turn rod (13) out of 6V7941 Compressor Assembly (15) until knob (14) is 25.4 mm (1.0 in.) from the compressor body. Install 6V7941 Compressor Assembly (15) in the hole plug (9) was removed from. NOTE: The 6V7941 C0mpressor Assembly is used to compress the overfueling spring. The overfueling spring must be compressed to get an accurate fuel setting measurement.
10. Insert 6V7942 Hook (Il) into the hole that plug (9) was removed from. Engage the end of hook (II) with collar (12) and pull toward the rear of the governor housing until the collar stops moving. This will make sure the fuel rack stops against the timing pin. This is the rack zero position.
B\l7312X2
6V7941 COMPRESSOR ASSEMBLY 13. Rod. 14. Knob.
867321 X2
6V7942 HOOK IN USE 11. 6V7942 Hook. 867314X2, ;
.. B74901X1
COMPRESSOR ASSEMBLY INSTALLED 15. 6V7941 Compressor Assembly.
CUTAWAY VIEW OF GOVERNOR 11. Hook. 12. Collar.
48
14. Move the governor controllever to the FUEL OFF position. Use two SI614 Bolts and install 6V2017 Governor Adjustment Tool (16). Be sure the end of the tool is behind the governor linkage, and that the flange is completely against the governor housing (the filter screen may have to be removed).
I""-',
FUEL SYSTEM
NOTE: If it is expected to be necessary to change the setting, install the outer part of 6V2106 Rack Adj usting Tool (17) along the left side of the 6V20 17 Adjusting Tool when the 6V20l7 Adjusting Tool is installed.
TESTING AND ADJUSTING
(9. If the air fuel ratio control setting is not cor
rect, use 6V2106 Rack Adjustment Tool (17) to loosen the locknut and turn the adjustment screw (18). Turn the screw clockwise to de crease the amount of fuel possible (less rack travel) at the limited rack position. NOTE: One revolution of the adjustment screw will change the setting approximately 0.79 mm (.031 in.).
ADJUSTING TOOL INSTALLED 16. 6V2017 Governor Adjustment Tool.
15. Move the governorcontro] to the FULL LOAD position and hold in this position. 16. Turn the overfueling spring com pressor rod IN (clockwise) until the indicator hands move approximately] mm. 17. Slowly turn the rod OUT (counterclockwise) until the indicator hand stops moving. This is the AIR FUEL RATIO CONTROL SET TING. NOTE: There will be a small initial movement of the dial indicator hands, then, they will stop moving while the rod is turned out for another I Y2 turns. Now the indicator hands will begin to move again and will follow the turning of the rod until the setting is reached. It is important that the rod be turned slowly so that the rack can follow the governor components. 18. Make reference to the FUEL SETTING IN FORMATION for the correct air fuel ratio setting and compare to the dial indicator read mg.
ADJUSTMENT SCREW FOR GOVERNOR 18. Adjustment screw.
NOTE: The dial indicator hands will not follow the turning of the adj ustment screw. It will be necessary to repeat Steps 15 through 19 until the correct setting is obtained.
FUEL SETTING PROCEDURE Tools Needed:
6V4186 Timing Pin.
6V2106 Rack Adjustment Tool Group.
6V7941 Compressor, Overfueling Spring.
6V2031 Rack Position Indicator Group.
9S229 Contact Point, 9.7 mm (.38 in.) long.
5P4814 Collet.
6V3075 Dial Indicator.
8S4627 Circuit Tester.
The static fuel setting can be done with the fuel injection pump and governor on or off the engine. 1. Remove the fuel filter base and fuel line from the fuel injection pump housing and remove cover (1).
2. Install 5P4814 Collet (2) on 6V2014 Bracket Assem bly (3).
GOVERNOR LINKAGE ADJUSTMENT
3. Install the bracket assembly on the fuel pump, housing. Lever (5) on the bracket assembly must be in slot (4) on the fuel rack. Push up on the bracket assembly while the bolts are tight ened.
17. 6V2106 Rack Adjustment Tool Group.
49
FUEL SYSTEM
TESTING AND ADJUSTING
After the bracket assembly is tightened to the pump housing, shaft (6) must have axial (in and out) movement. If there is no axial movement of shaft (6), check to be sure lever (5) is in the slot on the fuel rack and that the bracket assem bly is installed correctly. Check to make Sure that lever (5) is not bent. Lever (5) must be perpendicular (at right angle) to the mounting face of the bracket assembly.
BRACKET ASSEMBLY 5. Lever.
6. Shalt.
4. Put 95229 Contact Point, 9.7 mm (.38 in.) long on 6V3075 Dial Indicator (7) and install dial indicator in collet (2).
FUEl. INJECTION PUMP AND GOVERNOR 1. Cover.
DIAL INDICATOR INSTALLED 7. 6V3075 Dial Indicator.
5. Remove air fuel ratio control (8) from the rear of the governor housing if equipped. .'"i BRACKET ASSEMBLY INSTALLED 2. 5P4814 Collet. 3. Bracket assembly.
GOVERNOR 8. Air fuel ratio control. COVER REMOVED 4. Slot on fuel rack.
50
6. Remove plug (9) from the rear of the governor housing.
FUEL SYSTEM
TESTING AND ADJUSTING
B67321X2; REAR OF GOVERNOR HOUSING
6V7942 HOOK IN USE
9. Plug.
11. 6V7942 Hook.
7. Move the governor control lever to the FU EL OFF position (rotate governor shaft clock wise).
CUTAWAY VIEW OF GOVERNOR 11. Hook. 12. Collar.
TIMING PIN INSTALLED 10. 6V4186 Timing Pin.
8. Install 6V4186 Timing Pin (10) in the hole in the bracket assembly. Push timing pin in until contact is made with the fuel rack. Hold the timing pin gently against the fuel rack for Steps 9 and 10. If too m uch force is used to hold the timing pin the fuel rack can stick and cause an incorrect zero reading.
11. With the hook still pulled toward the rear of the governor, loosen collet (2) and adjust the revolution counter on the dial indicatorto zero. Tighten the collet just enough to hold the indi cator in this position. Move the dial of the indi cator to get alignment of the pointer and zero. 12. Remove timing pin (10).
B67312X2
9. H old the governo I' control lever in the HI G H IDLE position (rotate governor shaft counter clockwise). 10. Insert 6V7942 Hook (11) into the hole that plug (9) was removed from. Engage the end of hook (11) with collar (12) and pull toward the rear of the governor housing until the collar stops moving. This will make sure the fuel rack stops against the timing pin. This is the rack zero position.
J
6V7941 COMPRESSOR ASSEMBLY 13. Rod.
14. Knob.
51
TESTING AND ADJUSTING
FUEL SYSTEM
13. Turn rod (13) out of 6V7941 Compressor Assembly (15) until knob (14) is 25.4 mm (1.0 in.) from the compressor body. Install 6V794l Compressor Assembly (IS) in the hole plug (9) was removed from.
16. Turn rod (13) of compressor assembly (15) in (clockwise) until the light in circuit tester (15) goes off and the dial indicator hands move an additional 2 mm in the negative (-) direction after the light goes out.
NOTE: The 6V7941 Compressor Assembly is used to compress the overfueling spring. The overfueling spring must be compressed to get an accurate fuel setting measurement.
NOTICE DO NOT turn the rod any further in if the rod begins to tighten. Damage to the governor can occur if the rod is turned in further. 17. Slowly turn rod (13) out (counterclockwise) until the circuit tester light just comes on. This is the static fuel setting. See the FUEL SET TING INFORMATION for the correct static fuel setting.
COMPRESSOR ASSEMBLY INSTALLED 15. 6V7941 Compressor Assembly.
NOTE: The procedure to check the fuel settings is different than the procedure to adjust the fuel settings. Follow Steps 13 through 18 to check the fuel settings. Follow Steps 19 through 24 to adjust the fuel settings on engines with a torque spring. Follow Steps 25 and 26 on engines with a stop bar. 14. Fasten the clip end of8S4627 Circuit Tester ( 16) to rack contact screw (17) and pu t the other end to a good electrical ground.
NOTE: When the rod is turned out, there will be a small initial movement of the dial indicator hands, then, they will stop moving while the rod is turned out for approximately another 112 turns. Now the indicator hands will begin to move again and will follow the turning of the rod until the setting is reached. It is important tha t the rod be turned slowly so that the rack can follow the governor com ponents.
18. This step is only for engines that have a torque spring. Contiuue to turn the rod out until the indicator hand stops moving. Then turn the rod out two additional turns. The reading on the indicator is the torque rise static setting. See the FUEL SETTING INFORMATION for the correct static torque rise setting.
i~
19. If the fuel setting 0 r the torque rise setting is
not correct, remove adjustment screw cover
(18) from the rear of the governor housing.
CHECKING STATIC FUEL SETTING 16. 8S4627 Circuit Tester. 17. Rack Contact Screw. 18. Adjustment Screw Cover.
15. Hold the governor control lever in the FUEL ON position (rotate lever fully counterclock wise).
ADJUSTMENT SCREW COVER REMOVED 19. Torque rise adjustment screw. 20. Fuel setting screw.
52
I!!'.
.-A
FUEL SYSTEM
TESTING AND ADJUSTING
20. Determine how much the settings will have to be changed (see example). Use the chart that follows to" determine how far the adjusting screws must be turned.
Example #3 Actual Reading:
-1.05 mm
Desired Setting:
-1.25 mm
Difference: ADJUSTMENT SCREW CHART
-_.
AMOUNT OF CHANGE
TURNS OF ADJUSTMENT SCREW
3.0 mm (.118 in.)
3%
2.8 mm (110 in.)
3'1,
2.6 mm (.102 in.)
3;1.
2.4 mm (.094 in ;,
3
2.2 mm (.087 in,i
I
2'j,
2.0 mm (.079 i:l)
2;;'
1.8 mm (.071 In.)
2;1,
0.20 mm
Negative numbers work differently than posItIve numbers. If one number (-1.25) has a larger digital value than another one (-1.05), the first number (-1.25) is actually less than the other one. There fore, in this example the "desired setting" is lower than the "actual reading." Turn the adjusting screw in (clockwise) approximately I! 4 turn. Recheck the new setting and readjust if necessary.
2
Example #4
1.4 mm (.055 in.)
1%
Actual Reading:
-2.77 mm
1.2 mm (.047 in.)
1%
1.0 mm (.039 in.)
1 'II
Desired Setting:
-1.85 mm
1.6 mm (.063 in,)
0.8 mm (.031 in.)
\
Difference:
1
I
0.6 mm (.024 In.)
¥,
0.4 mm (.016 in.)
'/2
0.2 mm (.OOB in.)
y"
Example #1
0.92 mm
The "desired setting" is higher than the "actual reading." Turn the adjusting screw out (counter clockwise) approximately 1VB turns. Recheck the new setting and readjust if necessary.
Actual Reading:
1.05 mm
Example #5
Desired Setting:
1.25 mm
Actual Reading:
+1.05 mm
Difference:
0.20 mm
Desired Setting:
-1.25 mm
Since "desired setting" is higher than "actual reading," turn adjusting screw ouf (counterclock wise) approximately I! 4 turn. Recheck the new setting and readjust if necessary.
Example #2
Difference:
2.30 mm
The "desired setting" is lower than the "actual reading." Turn the adjusting screw in approxi mately 2Ys turns.
Example #6
Actual Reading:
2.77 mm
Desired Setting:
1.85 mm
Difference:
0.92 mm
Since "desired setting" is lower than "actual read ing," turn adjusting screw in (clockwise) approxi mately I VB turn. Recheck the new setting and readjust if necessary.
Actual Reading:
-1.05 mm
Desired Setting:
+1.25 mm
Difference:
2.30 mm
The "desired setting" is higher than the "actual reading. " Turn the adjusting screw out approxi mately 2% turns.
53
FUEL SYSTEM
TESTING AND ADJUSTING
Engines With Torque Spring: 21. If both settings are to be increased, turn torque rise adjustment screw (19) out (counterclock wise) the same number of turns as fuel setting adjustment Screw (20) is going to be changed. If the static fuel setting is going to be decreased, it is not necessary to change the torque rise setting at this time.
ENGINE SPEED MEASUREMENT Tools Needed: 6V3121 Multitach Group or 6V4950 Injection Line Speed Pickup Group
22. Use 6V2106 Rack Adjnstment Tool Group (21) to loosen the locknuts for adjustment screws and to turn the adjustment screws. 23. Adjust the fuel setting screw the number of turns determined in Step 20. Always recheck the setting after each adjustment and adjust again if needed. 24. After the static fuel setting is correct, adjust the torque rise adjnstment screw the number of turns determined in Step 20. Always recheck the setting after each adjustment and adjust again if needed.
I
~~
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cl
~~~ ~.~~ ~ .
3
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0
n,1
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4
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B19988X1
6V3121 MULTITACH GROUP
1. Carrying case. 2. Power cable. 3. Tachometer genera tor. 4. Tachometer driver group. 5. Mullitach.
The 6V3121 M ultitach Group can measure engine speed from a tachometer drive on the engine. It also has the ability to measure engine speed from visual engine parts in rotation. Special Instruction Form No. SEHS7807 is with the 6V3121 Multitach Group and gives instrnctions for the test proced ure.
.'J.
The 6V4950 Injection Line Speed Pickup Group is another diagnostic tool ac~essory that can be used with the 6V21 00 M ultitach. It can be used on all Caterpillar Diesel Engines equipped with 6 mm (.25 in.) single wall fuel injection lines. With this pickup group, engine speed can be measured quickly, auto matically, and with an accuracy of ± I rpm. ADJUSTING FUEL SETTING
21. 6V2106 Rack Adjustment Tool Group.
Engines With Load Stop Bar
25. Use 6V2106 Rack Adjustment Tool Group (21) to loosen the locknut for the adjustment screw and to turn the adjustment screw. 26. Adjust the fuel setting screw the number of turns determined in Step 20. Always recheck the setting after each adjustment and adjust again if needed.
J
B51239X1
6V4950 INJECTiON LINE SPEED PICKUP GROUP 6. 6V6114 Pickup. 7. 6V6113 Amplifier.
54
I
.I.
FUEL SYSTEM
TESTING AND ADJUSTING
Special Instruction Form No. SEHS8029 is with the group and gives instructions for use of the 6V4950 Injection Line Speed Pickup Group. GOVERNOR ADJUSTMENTS Low and High Idle Adjustment NOTICE A mechanic with training in governor adjust ments is the only one to make the adjustment to the low idle and high idle rpm.
874908X1 HIGH IDLE ADJUSTMENT
Engiue rpm must be checked with an accurate tachometer. Make reference to MEASURING ENGINE SPEED. NOTE: The corect low idle and high idle rpm are in the FUEL SETTING INFORMATION.
8" WARNING To help prevent an accident caused by parts in rotation, work carefully around an engine that has been started.
Start the engine and run until the temperature of normal operation is reached. Check low and high idle rpm with no load on the engine. If an ad justment is necessary, use the procedure that fol lows: 1. To adjust the LOW IDLE rpm, start the en
gine and run with the governor in the low idle position. Loosen the locknut for low idle screw (2). Turn the low idle screw to get the correct low idle rpm. Increase engine speed and return to low idle and check low idle speed again. Tighten the locknut. ,B74907X1
3. High idle screw.
2. To adjust the HIG H IDLE rpm, cut the lock wire and remove cover (1). Start the engine and run with the governor in the high idle position. Loosen the locknut for high idle screw (3). Turn the high idle screw to get the correct high idle rpm. Decrease engine speed and return to high idle and check high idle rpm again. Tighten the locknut and install cover (I) and lock wire and seal. Dashpot Screw Adjustment The dash pot adjustment screw does not nor mally need adjustment from the factory setting. If the engine is slow to change rpm with a change in load, it is possible that the dash pot adjustment screw is not adjusted correctly. I. Turn dashpot adjustment screw (1) in (clock wise) until it stops.
2. Turn dashpot adjustment screw out (counter clockwise) 1/2 ± 1/4 turn.
B74907X2
L.OW AND HIGH IDLE ADJUSTMENT
DASH POT SCREW ADJUSTMENT
1. Cover. 2. Low idle screw.
1. Dashpol adjustment screw.
55
FUEL SYSTEM
TESTING AND ADJUSTING
Checking Set Point (Balance Point) The set point check of the engine is a method to make a diagnosis of engine performance.
Use the procedure that follows to check the set point. Make reference to TECHNIQUES FOR LOADING ENGINES in Special Instruction Form No. SEHS70S0.
NOTE: It is important. to the correct operation of the vehicle that the set point (balance point) is ad justed to the correct specifications. There is a new and more accurate method for checking the "set point," formerly called the balance point, of the engine. If the tools for the new method are not available, there is an alternate method for checking the "set point." Tools Needed: 6V4060 Engine Set Point Indicator Group.
B74907X3
TERMINAL LOCATION 1. Brass terminal screw.
-
B54624Xl
6V4060 ENGINE SET POINT INDICATOR GROUP
The 6V4060 Engine Set Point Indicator Group with the 6V2100 Muititach can be used to check the set point. Special Instruction Form No. SEHS793 J gives instructions for installation and use of this tool group.
I. Connect a tachometer which has good accuracy
to the tachometer drive.
2. Connect the clip end of the 8S4627 Circuit
Tester to the brass terminal screw (I) on the
governor housing. Connect the other end of the
tester to a place on the fuel system which is a
good ground connection.
.~~~
A, WARNING Work carefully around an engine that is run ning. Engine parts that are hot, or parts that are moving, can cause personal injury.
Alternate Method Tools Needed: 854627 Circuit Tester. 6V3121 Multitach Group.
If the set point and the high idle speed are correct, the fuel system operation of the engine is correct. The set point for the engine is: A. At 20 rpm greater than full load speed.
B. The rpm where the fuel setting screw just makes contact with the torque spring or stop bar.
e. The rpm where the engine gets the maximum amount of fuel per stroke. D. The rpm where the engine has maximum horsepower 0 utput.
56
3. Start the engine. 4. With the engine at normal conditions for opera
tion, run the engine at high idle.
5. Make a record of the speed of the engine at high idle.
6. Add load on the engine slowly until the circuit tester light just comes on (minimum light out put). This is the set point. 7. Make a record of the speed (rpm) at the set point. 8. Repeat Step 6 several times to make sure that the reading is correct.
'1'1
FUEL SYSTEM
TESTING AND ADJUSTING
9. Stop engine. Make a comparison of the records
from steps 5 and 7 with the information from
the FUEL SETTING INFORMATION.
10. If the set point is correct, the governor setting is
adj usted correctly. If the set point is not correct,
adjust the high idle rpm until you get the correct
set point. NOTICE Do not adjust rpm above the range for HIGH IDLE given in FUEL SETTING INFORMATION. Damage to engine can result if setting is too high.
57
I
.
..
..
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