Testing and Adjusting

Usage:

Problem Solving

1. Starting Motor Fails to Crank

2. Engine Fails to Start

3. Misfiring

4. Stalls at Low Speed

5. Erratic Engine Speed

6. Low Power

7. Excessive Vibration

8. Heavy Combustion Knock

9. Crankshaft does not Turn Freely

10. Valve Train Clicking Noise

11. Oil in Coolant

12. Mechanical Knock

13. Excessive Fuel Consumption

14. Loud Valve Train Noise

15. Little Rocker Arm Movement and Excessive Lash

16. Low Valve Stem Projection

17. Spring Retainer Free

18. Slobber

19. Valve Lash Close-Up

20. Premature Engine Wear

21. Coolant in Engine Lubricating Oil

22. Excessive Black or Gray Smoke

23. Excessive White or Blue Smoke

24. Low Engine Oil Pressure

25. High Lubricating Oil Consumption

26. Abnormal Engine Coolant Temperature

27. Alternator or Generator Fails to Charge

28. Alternator or Generator Charging Rate Low or Unsteady

29. Alternator or Generator Charging Rate Excessive

30. Noisy Alternator or Generator

Fuel System

Testing 9L9263 And 9L8965 Fuel Injection Nozzles

8S2242 Nozzle Testing Group.8S2245 Injector Cleaning Tool Group.9S7354 Torque Wrench.9S3093 Adapter.

Before testing a fuel injection pump or nozzle from an engine that is misfiring or puffing black smoke, a simple check can be made to determine which cylinder is causing the difficulty.

With the engine running at a speed that makes the misfiring most pronounced, momentarily loosen the fuel line nut on an injection pump sufficiently to "cut out" that cylinder. Check each cylinder in the same manner. If one is found where loosening makes no difference in the irregular operation or causes puffing of black smoke to cease, the pump and valve for only that cylinder need be tested.

Exhaust port temperature, when the engine is running at low idle speed, can be an indication of injection nozzle condition. Low temperature at an exhaust manifold port, indicates no fuel to the cylinder and a possibility of a clogged nozzle. Exceptionally high exhaust port temperature may indicate excess fuel injection caused by poor fuel cut off.

NOTE: Do not attempt to test or disassemble nozzles without the proper service tools.

Before testing, remove loose carbon from the tip with the 8S2258 Brass Wire Brush. Remove the carbon seal dam and clean the groove and the body below the groove in the same manner. Any staining in this area is normal and not detrimental to the nozzle body. Carbon accumulations should be removed, but excessive brushing will remove the coating on the nozzle. Perform all test before cleaning or adjusting a nozzle. A test may show that the nozzle can not be used again.

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When testing, keep the nozzle tip directed away from the operator and into the 8S2270 Fuel Collector to contain the spray. Fuel from the spray orifices can penetrate clothing and skin causing serious infection.

Connect nozzle (4) to tester (1) using tube assembly (2) and adapter (3). The nozzle may be tightened by hand if the 1H1023 Seal is not damaged.

The 9S3093 Adapter (3) for the nozzle tester is needed on 9L9263 Nozzles but is not needed for 9L8965 Nozzles.

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NOTICE

Always use clean Kent-Moore J23300-585 or Shell 66631 calibration oil or equivalent when testing. Dirty test oil will damage nozzle components.

NOTE: Kent-Moore J23300-585 calibration oil may be purchased from Kent-Moore Corp. 1501 South Jackson St., Jackson, Michigan 49203. Shell 66631 calibration oil may be purchased from Shell Oil Company.

CONNECTING NOZZLE TO TESTER
1. 8S2267 Nozzle Tester. 2. 8S2268 Tube Assembly. 3. 9S3093 Adapter. 4. Nozzle.

Opening Pressure Test

1. Close the gauge protector valve and the on-off valve. Open the pump isolator valve. Flush the nozzle by operating the tester for 10 to 15 strokes at a rate of 60 strokes per minute.

2. Open the gauge protector valve. Raise the pressure slowly until the nozzle valve opens. The gauge reading may drop sharply if the valve chatters, or may stay nearly constant when the valve opens. Opening pressures should be as listed in the chart. If opening pressure is less than 2200 psi (154.7 kg/cm²), do not use the nozzle again.

NOTE: Lack of chatter or atomized spray during Step 2 does not indicate a faulty valve.

NOTE: Used nozzles that have been cleaned, should be adjusted to 2750 to 2850 psi (193.3 to 200.4 kg/cm²) opening pressure.

3. Adjust opening pressure, if necessary as follows:

a) Remove the nozzle from the tester and secure it in the 8S2250 Nozzle Holding Tool. Loosen the adjusting screw locknut. Reconnect the nozzle, with the tip facing downward, to the tester.

b) Back out the lift adjusting screw far enough to prevent bottoming when the pressure adjusting screw is turned.

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NOTICE

Failure to back out the lift adjusting screw far enough will result in a bent valve or damage to the valve seat in the next step.

c) Turn the pressure adjusting screw clockwise to increase, or counterclockwise to decrease opening pressure. Do not tighten locknut at this time.

Valve Lift Adjustment

1. With the opening pressure set correctly and while pumping test oil through the nozzle, hold the pressure adjusting screw and slowly turn the lift adjusting screw clockwise until the fuel ceases to flow.

2. Check to be sure the valve is bottomed by raising the pressure 200 to 500 psi (14.06 to 35.15 kg/cm²) OVER the nozzle opening pressure.

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NOTICE

Do not bend the valve or damage the valve seat by bottoming with too much force.

NOTE: Some fuel may collect at the tip but a rapid dribble should not be apparent.

3. Back out the lift adjusting screw 3/4 ± 1/8 of a turn.

4. Hold the pressure adjusting screw and tighten the locknut. See subject, TIGHTENING LOCKNUT.

5. Recheck the opening pressure.

Checking Seat Condition

1. Wrap the top of the fuel nozzle body (adjusting screw end) with a shop towel to absorb the leakage. Close the gauge protector valve.

2. Point the nozzle tip into the 8S2270 Fuel Collector and operate the pump rapidly for at least five strokes to firmly seat the valve. Open the gauge protector valve. Dry the nozzle tip thoroughly.

3. Raise the pressure at the nozzle to 250 to 300 psi (17.6 to 21.1 kg/cm²) UNDER opening pressure. If more than 3 drops of fuel should appear on the tip in 15 seconds, clean or replace the nozzle.

Spray Pattern

NOTE: The valve lift must be set properly before checking spray pattern. The amount of lift affects this characteristic.

1. Close the gauge protector valve and the on-off valve. Open the pump isolator valve.

2. Point the nozzle tip into the 8S2270 Fuel Collector.

3. Raise pressure slowly and observe the spray pattern when fluid begins to flow through the nozzle. The spray must be equal and uniform through all four orifices. Any deviation, either vertically or horizontally, indicates an unsatisfactory nozzle. See the spray pattern diagram.

NOZZLE SPRAY PATTERN ANALYSIS

NOTE: This test may be difficult if the nozzle valve chatters, due to the high flow rate. However, analyze the spray pattern as carefully as possible.

Return Leakage Check

1. Loosen the connector nuts and reposition the nozzle tip slightly above the horizontal position. Tighten the connector nuts.

2. Operate the tester to raise the pressure to 1400 to 1600 psi (98.4 to 112.5 kg/cm²).

3. Observe the leakage from the return at the top (adjusting screw end) of the nozzle. After the first drop falls, leakage should be 1 to 10 drops in 15 seconds with Kent-Moore J23300-585 or Shell 66631 calibration oil or equivalent at 65° to 75° F (18° to 24° C). More than 10 drops in 15 seconds indicates worn or faulty parts, and the nozzle should be replaced.

Tightening Locknut

1. Remove the nozzle from the tester and place in the holding tool (3). Secure the tool in a vise. Do not clamp any part of the nozzle body directly in the vise.

2. Hold the pressure adjusting screw stationary and using torque wrench (1) and adapter (2), tighten the locknut to 70 to 80 lb. in. (80.7 to 92.2 cm.kg).

TIGHTENING LOCKNUT
1. 9S7354 Torque Wrench. 2. 8S2253 or 2P5487 Adapter. 3. 8S2250 Nozzle Holding Tool.

Testing 9L7883 Fuel Injection Nozzles

8S2242 Nozzle Testing Group.8S2245 Injector Cleaning Tool Group.9S7354 Torque Wrench.9S3093 Adapter.8H8505 Combination Wrench.8H8502 Combination Wrench.8S2274 Socket.8S1589 Socket.Screwdriver.

Before testing a fuel injection pump or nozzle from an engine that is misfiring or puffing black smoke, a simple check can be made to determine which cylinder is causing the difficulty.

Exhaust port temperature, when the engine is running at low idle speed can be an indication of injection nozzle condition. Low temperature at an exhaust manifold port, indicates no fuel to the cylinder and a possibility of a clogged nozzle. Exceptionally high exhaust port temperature may indicate excess fuel injection caused by poor fuel cut off.

NOTE: Do not attempt to test or disassemble nozzles without the proper service tools.

Before testing, remove loose carbon from the tip with the 8S2258 Brass Wire Brush. Remove the carbon seal dam and clean the groove and the body below the groove in the same manner. Any staining in this area is normal and not detrimental to the nozzle body. Carbon accumulations should be removed, but excessive brushing will remove the coating on the nozzle. Perform all tests before cleaning or adjusting a nozzle. A test may show that the nozzle can not be used again.

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Connect nozzle (4) to tester (1) using tube assembly (2) and adapter (3). The nozzle may be tightened by hand if the 1H1023 Seal is not damaged.

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NOTICE

Always use clean Kent-Moore J23300-585 or Shell 66631 calibration oil or equivalent when testing. Dirty test oil will damage nozzle components.

CONNECTING NOZZLE TO TESTER
1. 8S2267 Nozzle Tester. 2. 8S2268 Tube Assembly. 3. 9S3093 Adapter. 4. Nozzle.

Opening Pressure Test

1. Close the gauge protector valve and the on-off valve. Open the pump isolator valve. Flush the nozzle by operating the tester for 10 to 15 strokes at a rate of 60 strokes per minute.

NOTE: Lack of chatter or atomized spray during Step 2 does not indicate a faulty valve.

NOTE: Used nozzles that have been cleaned, should be adjusted to 2700 to 2900 psi (189.8 to 203.9 kg/cm²) opening pressure.

3. Adjust opening pressure, if necessary as follows:

a) Remove the nozzle from the tester and secure it in the nozzle holding tool (7). Loosen the lift adjusting screw locknut (5). Loosen the lift adjusting screw (6) two or three turns counterclockwise.

LOOSENING LOCKNUT
4. Nozzle. 5. Locknut. 6. Lift adjusting screw. 7. 8S2250 Nozzle Holding Tool.

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NOTICE

If the lift adjusting screw (6) is not loosened, the valve can be bent or the valve seat damaged when assembled in Step e.

b) Loosen the pressure screw (8). Remove the nozzle from the holder.

LOOSENING PRESSURE SCREW
8. Pressure screw.

c) Tilt the nozzle slightly down from the vertical position and remove the pressure screw assembly and shims.

NOTE: If the shims do not come out of the nozzle, invert the nozzle and let the shims, spring, and spring seat fall into your hand. The valve may come out by its own weight and must be handled carefully by the stem.

d) Increase the opening pressure by adding a 4N5730 Shim. The 4N5730 Shim is .005 in. (0.13 mm) thick and will increase the opening pressure approximately 250 psi (17.8 kg/cm²). A maximum of two shims can be added to increase the opening pressure.

PRESSURE SCREW AND SHIMS
8. Pressure screw. 9. Shims.

e) Assemble the nozzle being sure the thickest shim is against the pressure screw assembly as shown. Put the nozzle in the nozzle holding tool (7). Put the holding tool in a vise and tighten the pressure screw (8) to 75 to 80 lb.in. (86.5 to 92.2 cm.kg).

TIGHTENING PRESSURE SCREW

f) Remove the nozzle from the holding tool. Connect the nozzle, with the tip facing downward, to the tester. Point the nozzle tip into the 8S2270 Fuel Collector. Check the opening pressure. If the opening pressure is not within specifications, repeat the preceding Steps.

Valve Lift Adjustment

1. With the opening pressure set correctly and while pumping test oil through the nozzle, hold the lift adjusting screw locknut and slowly turn the lift adjusting screw clockwise until the fuel ceases to flow.

2. Check to be sure the valve is bottomed by raising the pressure 200 to 500 psi (14.06 to 35.15 kg/cm²) OVER the nozzle opening pressure.

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NOTICE

Do not bend the valve or damage the valve seat by bottoming with too much force.

NOTE: Some fuel may collect at the tip but a rapid dribble should not be apparent.

3. Back out the lift adjusting screw 3/4 ± 1/8 of a turn.

4. Hold the lift adjusting screw with a screwdriver and tighten the locknut just enough that the screw will not turn.

TIGHTENING LOCKNUT

5. Put the nozzle in the 8S2250 Nozzle Holding Tool. Put the holding tool in a vise and tighten the locknut to 35 to 40 lb. in. (40.4 to 46.1 cm.kg).

TIGHTENING LOCKNUT

Checking Seat Condition

1. Wrap the top of the fuel nozzle body (pressure screw end) with a shop towel to absorb the leakage. Close the gauge protector valve.

2. Point the nozzle tip into the 8S2270 Fuel Collector and operate the pump rapidly for at least five strokes to firmly seat the valve. Open the gauge protector valve. Dry the nozzle tip thoroughly.

3. Raise the pressure at the nozzle to 250 to 300 psi (17.6 to 21.1 kg/cm²) UNDER opening pressure. If more than 3 drops of fuel should appear on the tip in 15 seconds, clean or replace the nozzle.

Spray Pattern

NOTE: The valve lift must be set properly before checking spray pattern. The amount of lift affects this characteristics.

NOZZLE SPRAY PATTERN ANALYSIS

1. Close the gauge protector valve and the on-off valve. Open the pump isolator valve.

2. Point the nozzle tip into the 8S2270 Fuel Collector.

NOTE: This test may be difficult if the nozzle valve chatters, due to the high flow rate. However, analyze the spray pattern as carefully as possible.

Return Leakage Check

1. Loosen the connector nuts and reposition the nozzle tip slightly above the horizontal position. Tighten the connector nuts.

2. Operate the tester to raise the pressure to 1400 to 1600 psi (98.4 to 112.5 kg/cm²).

3. Observe the leakage from the return at the top (pressure screw end) of the nozzle. After the first 2 drops fall, leakage should be 1 to 10 drops in 15 seconds with Kent-Moore J23300-585 or Shell 66631 calibration oil or equivalent at 65° to 75° F (18° to 24° C). More than 10 drops in 15 seconds indicates worn or faulty parts, and the nozzle should be replaced.

Locating Top Center Compression Position For No. 1 Piston

No.1 piston on the compression stroke at top center (TDC) is the reference point for all timing procedures.

INSTALLING BOLT
1. 1D4539 Bolt, 5/16"-18NC, 2.5 in. (63.5 mm) long. 2. Timing hole. 3. Hole.

Remove the plug from timing hole (2) in the front cover and insert a 5/16"-18NC bolt (1), 2.5 in. (63.5 mm) long. The cover retaining bolt from hole (3) may be used.

Turn the crankshaft CLOCKWISE (as viewed from front of engine) until bolt (1) threads into the camshaft drive gear.

Remove the right side valve cover (the two valves at the right front of the engine are the intake and exhaust valves for No. 1 cylinder).

The intake and exhaust valves of No. 1 cylinder should now be closed and timing pointer should align with TDC-1 mark on pulley or damper. The No. 1 piston is now positioned at top center on the compression stroke.

Fuel Flow Check Of Timing Using 2P8256 Engine Timing Decal

1P540 Flow Checking Tool Group.5D9231 Adapter.2P8256 Engine Timing Decal.Container for collecting fuel.

It is not necessary to remove the rocker arm assembly and fuel injection nozzle to fuel flow check the static timing if you use the 2P8256 Engine Timing Decal. The decal has timing marks for both the 5.96 in. (151.4 mm) diameter crankshaft pulleys and the 7.96 in. (202.2 mm) diameter crankshaft damper pulleys.

Before installing the decal, be sure the TDC-1 mark on the pulley or damper is in alignment with the pointer.

INSTALLING BOLT
1. 1D4539 Bolt, 5/16"-18NC, 2.5 in. (63.5 mm) long. 2. Timing hole. 3. Hole.

Remove the plug from timing hole (2) in the front cover and insert a 5/16"-18 bolt (1), 2.5 in. (63.5 mm) long. The cover retaining bolt from hole (3) may be used.

Turn the crankshaft CLOCKWISE (as viewed from front of engine) until bolt (1) threads into the camshaft drive gear.

TIMING MARK ALIGNMENT
4. TDC-1 mark. 5. Pointer.

If the TDC-1 mark (4) and the pointer (5) are in alignment, install the decal with the TDC mark on the decal in alignment with the TDC-1 mark (4) and the arrow on the decal in the down position as shown.

DECAL INSTALLED

With the 2P8256 Engine Timing Decal installed on the pulley or damper assembly, use the following procedure to check the static timing.

1. Disconnect No. 1 fuel line from injection pump and connect tube assembly (6) to injection pump. Position tube assembly (6) to slant slightly upward.

2. Disconnect the fuel line from fuel filter to fuel transfer pump. Connect pressure tank (9) to the disconnected fuel line using hose assembly (8) and a 5D9231 Adapter.

3. Turn on switch to energize the fuel solenoid valve, or connect a 12 volt source to the engine with the negative lead to ground, and the positive lead to fuel solenoid valve to energize the fuel solenoid.

4. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 30°.

5. Move governor control lever to the full fuel-on position and place a container (7) under the end of tube assembly (6) to collect the fuel.

6. Pressurize 1P539 Tank (9) to 10 to 15 psi (0.70 to 1.05 kg/cm²) and slowly rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until fuel flow from tube assembly (6) is reduced to 6 to 12 drops per minute.

7. Timing is correct when fuel flow is 6 to 12 drops per minute and the timing pointer is at the correct number of degrees on the decal. If the timing is wrong, see the subject FUEL FLOW METHOD OF ENGINE TIMING.

CHECKING FUEL FLOW
6. 7M1999 Tube Assembly. 7. Container. 8. 5J4634 Hose Assembly. 9. 1P539 Pressure Tank.

NOTE: Do not use a timing light with the decal to check the timing.

Fuel Flow Method of Engine Timing

Engines with Taper Drive for Fuel Injection Pump

FT887 or 8S2291 Timing Pin.5D9231 Adapter.1P540 Flow Checking Tool Group.9S8520 Puller Group.8S2298 Adapter Group.9S5031 Deep Well Socket.9M9268 Dial Indicator.1P5550 Fuel Cam Locking Tool.8H8557 Ratchet.9S1730 (1 1/8") Socket.Suitable container for collecting fuel.

ROTATING ENGINE
1. 8H8557 Ratchet. 2. 9S1730 (1-1/8") Socket.

Refer to Special Instruction (FM035709) for complete and detailed instructions for the fuel flow method of engine timing.

1. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until timing pin drops into the timing slot in the fuel pump camshaft.

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NOTICE

Make sure starter is not accidentally engaged during engine crankshaft rotation.

2. Remove the timing pin.

3. Remove right side valve cover, fuel return line, rocker arm assembly and No. 1 fuel injection.

4. Install the adapter group (4) and dial indiator (3) in the No. 1 cylinder and "zero" the indicator.

DIAL INDICATOR INSTALLED
3. 9M9268 Dial Indicator. 4. 8S2298 Adapter Group.

5. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 30°.

6. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until dial indicator reads maximum travel. Adjust indicator if required.

7. Disconnect No. 1 fuel line from injection pump and connect tube assembly (5) to injection pump. Position tube assembly (5) to slant slightly upward.

8. Disconnect the fuel outlet line at fuel filter. Connect the pressure tank (8) to the fuel outlet line at the fuel filter with hose assembly (7) and adapter (9).

9. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 30°.

CHECKING FUEL FLOW
5. 7M1999 Tube Assembly. 6. Suitable container. 7. 5J4634 Hose Assembly. 8. 1P539 Pressure Tank.

CONNECTING HOSE ASSEMBLY
7. 5J4634 Hose Assembly. 9. 5D9231 Adpater.

10. Move governor lever to the full fuel-on position and place container (6) under the end of tube assembly (5) to collect the fuel.

11. Turn on switch to energize the fuel solenoid valve, or connect a 12 volt battery to the engine with negative ground, and the positive lead to fuel solenoid valve to energize the fuel solenoid.

12. Pressurize tank (8) to 10 to 15 psi (0.70 to 1.05 kg/cm²) and slowly rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until fuel flow from tube assembly (5) is reduced to 6 to 12 drops per minute.

13. If engine is timed correctly, the dial indicator reading (3) will correspond with that in the chart.

NOTE: If indicator reading does not correspond to that specified in the chart, proceed as follows.

14. Install the fuel cam locking tool (10) in the fuel injection pump timing hole and lock the fuel pump camshaft in position.

LOCKING FUEL INJECTION CAMSHAFT
10. 1P5550 Fuel Cam Locking Tool.

15. On engines equipped with the hydraulic governor, loosen the fuel injection pump camshaft drive gear by removing tachometer drive shaft with a 9S5031 5/8 in. Deep Well Socket. Using the puller group (11), thread the 9S8528 Bolt Assembly into the camshaft. Do not force the bolt assembly. It should thread easily. Install the 9S8527 Bolt by threading it into the gear carrier or adapter. Then tighten the 9S8527 Bolt with a wrench until the gear carrier or adapter "pops" loose. On engines equipped with the "max-min" governor loosen the automatic timing advance retaining bolt with a 9/16 in. deep well socket. The bolt will first feel loose, then it will tighten again when the taper drive on the carrier starts to separate from the camshaft.

LOOSENING CAMSHAFT DRIVE GEAR (Engines Equipped with Hydraulic Governor)
11. 9S8520 Puller Group.

16. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 90°.

17. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until indicator (3) reads .200 in. (5.08 mm), tighten bolt that seats taper hand tight. Continue rotating crankshaft in CLOCKWISE direction until indicator (3) reads the specified dimension for engine being timed given in chart following STEP 13.

18. On engines equipped with the hydraulic governor, tighten gear retaining bolt to 32 ± 2 lb. ft. (4.4 ± 0.3 mkg). On engines equipped with the "max-min" governor, tighten the automatic timing advance retaining bolt to 35 ± 2 lb. ft. (4.8 ± 0.3 mkg).

NOTE: To check for correct timing, repeat Steps 1 through 13.

Fuel Flow Method Of Engine Timing

Engines with Bolt On Drive for Fuel Injection Pump

FT887 or 8S2291 Timing Pin.5D9231 Adapter.1P540 Flow Checking Tool Group.8H8572 Ratchet.8S2298 Adapter Group.9S5031 Deep Well Socket.9M9268 Dial Indicator.1P5550 Fuel Cam Locking Tool.8H8557 Ratchet.9S1730 (1 1/8") Socket.8S2274 Socket.8H8574 Extension.Suitable container for collecting fuel.

ROTATING ENGINE
1. 8H8557 Ratchet. 2. 9S1730 (1-1/8") Socket.

Refer to Special Instruction (FM035709) for complete and detailed instructions for the fuel flow method of engine timing.

1. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until timing pin drops into the timing slot in the fuel pump camshaft.

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NOTICE

Make sure starter is not accidentally engaged during engine crankshaft rotation.

2. Remove the timing pin.

3. Remove right side valve cover, fuel return line, rocker arm assembly and No. 1 fuel injector.

4. Install the adapter group (4) and dial indicator (3) in the No.1 cylinder and "zero" the indicator.

DIAL INDICATOR INSTALLED
3. 9M9268 Dial Indicator. 4. 8S2298 Adapter Group.

5. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 30°.

6. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until dial indicator reads maximum travel. Adjust indicator if required.

7. Disconnect No.1 fuel line from injection pump and connect tube assembly (5) to injection pump. Position tube assembly (5) to slant slightly upward.

CHECKING FUEL FLOW
5. 7M1999 Tube Assembly. 6. Suitable container. 7. 5J4634 Hose Assembly. 8. 1P539 Pressure Tank.

8. Disconnect the fuel outlet line at fuel filter. Connect the pressure tank (8) to the fuel outlet line at the fuel filter with hose assembly (7) and adapter (9).

CONNECTING HOSE ASSEMBLY
7. 5J4634 Hose Assembly. 9. 5D9231 Adapter.

9. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 30°.

10. Move governor lever to the full fuel-on position and place container (6) under the end of tube assembly (5) to collect the fuel.

12. Pressure tank (8) to 10 to 15 psi (0.70 to 1.05 kg/cm²) and slowly rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until fuel flow from tube assembly (5) is reduced to 6 to 12 drops per minute.

13. If engine is timed correctly, the dial indicator reading (3) will correspond with that in the chart.

NOTE: If indicator reading does not correspond to that specified in the chart, proceed as follows.

14. Install the fuel cam locking tool (10) in the fuel injection pump timing hole and lock the fuel pump camshaft in position.

LOCKING FUEL INJECTION CAMSHAFT
10. 1P5550 Fuel Cam Locking Tool.

15. Remove bolts (11) holding the fuel injection pump drive gear. Loosen tachometer drive assembly (12) one to two turns.

16. Rotate the engine crankshaft COUNTERCLOCKWISE (as viewed from front of engine) at least 90°.

TACHOMETER DRIVE ASSEMBLY
11. Bolts (three). 12. Tachometer drive assembly.

17. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until the indicator reads the specified dimension listed in the chart.

18. Install bolts (11) holding fuel injection pump drive gear. Tighten bolts to 32 ± 5 lb. ft. (4.4 ± 0.7 mkg). Tighten tachometer drive assembly (12) to 50 ± 10 lb. ft. (6.9 ± 1.4 mkg).

NOTE: If the bolts (11) will not go into the gear, the front cover must be removed and the gear rotated one or more teeth to get the alignment of the holes.

Fuel Injection Pump Camshaft Timing

Engines with Taper Drive for Fuel Injection Pump

8S2291 or FT887 Timing Pin.8H8572 Drive Ratchet.9S8520 Puller Group.9S5031 Deep Well Socket.

1. Remove timing slot plug (1) and insert timing pin.

TIMING SLOT PLUG
1. Plug.

2. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until the timing pin drops into the timing slot in the camshaft.

3. Remove the plug from timing hole (3). Insert bolt (2) through the cover and thread it into the timing gear. The cover retaining bolt from hole (4) may be used.

INSTALLING BOLT
2. 1D4539 Bolt, 5/16"-18NC, 2.5 in. (63.5 mm) long. 3. Timing hole. 4. Hole.

4. If the timing pin is in the slot in the fuel injection pump camshaft, and bolt (2) is threaded into the timing gear through timing hole (3), the fuel injection pump camshaft is correctly timed to the engine crankshaft.

NOTE: If bolt (2) will not thread into the timing gear with the timing pin in the fuel injection pump camshaft timing hole, proceed as follows.

5. Remove the tachometer drive adapter on the front cover.

6. On engines equipped with the hydraulic governor, loosen the fuel injection pump camshaft drive gear by removing tachometer driveshaft with a 9S5031 (5/8 in.) Deep Well Socket. Using the puller group (5), thread the 9S8528 Bolt Assembly into the camshaft. Do not force the bolt assembly. It should thread easily. Install the 9S8527 Bolt by threading it into the gear carrier or adapter. Then tighten the 9S8527 Bolt with a wrench until the gear carrier or adapter "pops" loose.

On engines equipped with the "max-min" governor loosen the automatic timing advance retaining bolt with a 9/16 in. deep well socket. The bolt will first feel loose, then it will tighten again when the taper drive on the carrier starts to separate from the camshaft.

LOOSENING CAMSHAFT DRIVE GEAR (Engines Equipped with Hydraulic Governor)
5. 9S8520 Puller Group.

7. Turn crankshaft CLOCKWISE (as viewed from front of engine) until the bolt (2) threads into the timing gear and is centered in hole through front cover. This positions No.1 cylinder at top center compression. With the timing pin in the slot in the fuel pump camshaft, and the bolt through the cover and into the timing gear, the injection pump camshaft is timed to the engine.

8. On engines equipped with the hydraulic governor, tighten gear retaining bolt to 32 ± 2 lb. ft. (4.4 ± 0.3 mkg). On engines equipped with the "max-min" governor, tighten the automatic timing advance retaining bolt to 35 ± 2 lb. ft. (4.8 ± 0.3 mkg).

9. Recheck timing by removing the timing pin and bolt. Rotate the crankshaft two revolutions CLOCKWISE (as viewed from front of engine) and put the timing pin and bolt back in place.

10. Remove the bolt (2) from the timing gear and install in hole (4). Install the plug into timing hole (3).

11. Remove timing pin from timing slot in the camshaft and install plug into the fuel pump housing opening.

12. Install the tachometer drive adapter.

Fuel Injection Pump Camshaft Timing

Engines with Bolt On Drive for Fuel Injection Pump

8S2291 or FT887 Timing Pin8H8572 Drive Ratchet9S5031 Deep Well Socket8S2274 Socket8H8574 Extension

1. Remove timing slot plug (1) and insert timing pin.

TIMING SLOT PLUG
1. Plug.

2. Rotate the engine crankshaft CLOCKWISE (as viewed from front of engine) until the timing pin drops into the timing slot in the fuel injection pump camshaft.

3. Remove the plug from timing hole (3). Insert bolt (2) through the cover and thread it into the timing gear. The cover retaining bolt from hole (4) may be used.

INSTALLING BOLT
2. 1D4539 Bolt, 5/16 in.-18NC, 2.5 in. (63.5 mm) long. 3. Timing hole. 4. Hole.

NOTE: If bolt (2) will not thread into the timing gear with the timing pin in the fuel injection pump camshaft timing slot, proceed as follows.

5. Remove the tachometer drive adapter cover (5).

COVER LOCATION
5. Tachometer drive adapter cover.

6. Remove the bolts (6) holding the gear. Loosen the tachometer drive assembly (7) one to two turns.

TACHOMETER DRIVE ASSEMBLY
6. Bolts (three). 7. Tachometer drive assembly.

7. Turn crankshaft CLOCKWISE (as viewed from front of engine) until bolt (2) threads into the timing gear and is centered in hole through the front cover. This positions No.1 cylinder at top center compression. With the timing pin in the slot in the fuel injection pump camshaft, and the bolt through the front cover and into the timing gear, the fuel injection pump camshaft is timed to the engine.

8. Install the bolts (6) holding the gear. Tighten the bolts to 32 ± 5 lb. ft. (4.4 ± 0.7 mkg). Tighten the tachometer drive assembly to 50 ± 10 lb. ft. (6.9 ± 1.4 mkg).

NOTE: If the bolts (6) will not thread into the fuel injection pump camshaft, the front cover must be removed and the gear rotated one or more teeth to get the alignment of the holes.

9. Check the timing again by removing the timing pin and bolt. Rotate the crankshaft two turns CLOCKWISE (as viewed from front of engine) and put the timing pin into the slot in the fuel injection pump camshaft and the bolt in the timing gear.

10. Remove bolt (2) from the timing gear and install in hole (4). Install the plug into timing hole (3).

11. Remove the timing pin from the timing slot in the fuel injection pump camshaft and install plug into the hole in the fuel injection pump housing.

12. Install the tachometer drive adapter cover (5).

Fuel Pump Timing Dimension Setting

Engines Equipped With Hydraulic Governor and Taper Drive for Fuel Injection Pump

6F6922 Depth Micrometer.8S7167 Gauge.8S2280 Pointer Assembly.1F8747 or 1P7410 Timing Plate Assembly.1J6298 Bolt.2S932 Washer.9S5446 Shaft.8S2291 or FT887 Timing Pin.

The timing dimension should be checked to compensate for wear in the timing gears or lifters. This will assure that the point of fuel injection is correct. If the timing dimension is too small, injection will begin early, and, if too great, injection will be late.

The fuel injection pump housing must be removed from the engine to check or adjust the timing dimension. Before removing the fuel injection pump housing, position No.1 piston at top center, see the topic, LOCATING TOP CENTER COMPRESSION POSITION FOR NO.1 PISTON.

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NOTICE

Do not rotate the engine crankshaft with the fuel injection pump and governor removed from the engine unless the front cover and fuel injection pump camshaft drive gear have been removed. Without the support of the fuel injection pump camshaft bearing, the fuel pump drive gear may wedge between the camshaft front gear and the engine front cover. This wedging action may cause the engine camshaft drive gear to turn on the camshaft when the engine crankshaft is rotated.

1. Install pointer assembly (3) on the fuel pump housing and slide plate assembly (4) over the 9S5446 Shaft.

TIMING FIXTURE GROUP INSTALLED
1. 6F6922 Depth Micrometer. 2. 8S7167 Gauge. 3. 8S2280 Pointer Assembly. 4. 1F8747 or 1P7410 Timing Plate Assembly. 5. Bolt.

2. Assemble the shaft over the end of the fuel pump camshaft and secure it with the 1J6298 Bolt [7/16 in.-20NF, 3.5 in. (88.9 mm) long] and a 2S932 Washer. Do not tighten the bolt.

3. Install the timing pin through the fuel pump housing into the timing slot in the camshaft.

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NOTICE

Do not turn the camshaft with the timing pin installed.

4. Position timing plate (4) with the 0° mark aligned with pointer assembly (3). Tighten bolt (5) to secure the timing plate to the fuel pump camshaft and, REMOVE THE TIMING PIN.

5. Turn the timing plate clockwise until the degree setting for the pump to be checked aligns with the pointer assembly. The pumps are numbered 1 through 8 from the front (timing plate end) to the rear (governor end). The firing order is 1, 2, 7, 3, 4, 5, 6, 8.

6. With the timing plate indexed to the correct degree setting for the pump to be checked, install gauge (2) into the pump bore.

7. Use the depth micrometer (1) to measure timing dimension. The timing dimension is the space between the fuel pump counterbore and the top of the fuel pump lifter spacer. This dimension should be 3.728 ± .001 in. (94.69 ± 0.03 mm) at 16° BTC injection timing. On earlier 5.0 in. (127.0 mm) stroke engines with 12° BTC injection timing this dimension should be 3.746 ± .001 in. (95.15 ± 0.03 mm).

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NOTICE

The timing dimension is brought within tolerance by changing the complete lifter assembly. Do not attempt to remove or replace the spacers in the lifter assemblies. An improperly staked spacer can cause engine failure. Part number and thickness are marked on the replacement lifter assemblies.

8. To install new lifters, remove the hydraulic governor and the fuel rack. The lifters can then be lifted out with an 8S2293 Magnet.

9. To install fuel injection pump assemblies, refer to the topic, INSTALLING FUEL INJECTION PUMPS.

10. Install the fuel pump housing and all related components on the engine, and time the fuel pump camshaft to the engine. Refer to the topic, FUEL INJECTION PUMP CAMSHAFT TIMING.

Fuel Pump Timing Dimension Setting

Engines with Bolt On Drive for Fuel Injection Pump

6F6922 Depth Micrometer.8S7167 Gauge.8S2291 or FT887 Timing Pin.8S2280 Pointer Assembly.1P7410 or 1F8747 Timing Plate Assembly.9S5446 Shaft.1B572 Bolt.2S932 Washer.

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NOTICE

Do not rotate the engine crankshaft with the fuel injection pump and governor removed from the engine unless the front cover and fuel injection pump camshaft drive gear have been removed. Without the support of the fuel injection pump camshaft bearing, the fuel pump drive gear may wedge between the camshaft front gear and the engine front cover. This wedging action may cause the engine camshaft drive gear to turn on the camshaft when the engine crankshaft is rotated.

1. Install pointer assembly (1) on the fuel injection pump housing. Install pointer assembly (1) even with the front of O-ring groove (2) in the housing.

POINTER ASSEMBLY INSTALLED
1. 8S2280 Pointer Assembly.

2. Put plate assembly (3) on the 9S5446 Shaft.

3. Assemble the 9S5446 Shaft over the end of the fuel injection pump camshaft and secure it with the bolt (5) [7/16 in. - 20NF, 2.5 in. (63.5 mm) long] and a washer (4). Do not tighten bolt (5).

NOTE: If the 9S5446 Shaft does not have counterbore (6), bore it to a diameter of .666 ± .005 in. (16.92 ± 0.13 mm) and to a depth of .50 in. (12.7 mm).

TIMING FIXTURE GROUP INSTALLED
1. 8S2280 Pointer Assembly. 2. O-ring seal groove (in housing). 3. 1P7410 or 1F8747 Timing Plate assembly. 4. 2S932 Washer. 5. 1B572 Bolt.

9S5446 SHAFT
6. Counterbore in shaft.

4. Install the timing pin through the fuel injection pump housing into the slot in the camshaft.

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NOTICE

Do not turn the fuel injection pump camshaft with the timing pin installed.

5. Position timing plate (3) with the 0° mark in alignment with pointer assembly (1). Tighten bolt (5) to secure the timing plate to the fuel injection pump camshaft and, REMOVE THE TIMING PIN.

6. Turn the timing plate clockwise until the degree setting for the pump to be checked aligns with the pointer assembly. The pumps are numbered 1 through 8 from the front (timing plate end) to the rear (governor end). The firing order is 1, 2, 7, 3, 4, 5, 6, 8.

7. With the timing plate indexed to the correct degree setting for the pump to be checked, install 8S7167 Gauge into the pump bore.

8. Use the 6F6922 Depth Micrometer to measure timing dimension. The timing dimension is the space between the fuel pump counterbore and the top of the fuel pump lifter spacer. This dimension is 3.728 ± .001 in. (94.69 ± 0.25 mm). Fuel pump timing (BTC) is 16°.

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NOTICE

The timing dimension is brought within tolerance by changing the complete lifter assembly. Do not attempt to remove or replace the spacers in the lifter assemblies. An improperly staked spacer can cause engine failure. Part number and thickness are marked on the replacement lifter assemblies.

9. To install new lifters, remove the hydraulic governor and the fuel rack. The lifters can then be lifted out with an 8S2293 Magnet.

10. To install fuel injection pump assemblies, refer to the subject, INSTALLING FUEL INJECTION PUMPS.

11. Install the fuel pump housing and all related components on the engine, and time the fuel pump camshaft to the engine. Refer to the subject, FUEL INJECTION PUMP CAMSHAFT TIMING.

Checking Fuel Injection Pump Lifter Washer and Pump Plunger

When pump plunger wear becomes excessive, the lifter washer may also be worn so it will not make full contact with the end of a new plunger. To avoid rapid wear on the end of the new plunger, replace the lifters having washers showing visible wear.

WEAR BETWEEN LIFTER WASHER AND PLUNGER
Fig. A illustrates the contact surfaces of a new pump plunger and a new lifter washer. In Fig. B the pump plunger and lifter washer have worn considerably. Fig. C shows how the flat end of a new plunger makes poor contact with a worn lifter washer, resulting in rapid wear to both parts.

A pump can maintain a satisfactory discharge rate and yet be unserviceable because of delayed timing resulting from wear on the lower end of the plunger. When testing a pump which has been in use for a long time, check the plunger length with a micrometer. Discard the pump if the plunger measures less than the minimum length (worn) dimension.

Inspect the upper diameter of the plunger for wear. The performance of pumps worn in this manner can be checked as described in the Instructions for Fuel Injection Test Apparatus.

Removing And Installing Fuel Injection Pumps (Off Engine)

8S2283 Dial Indicator.3S3269 Contact Point.9S225 Bracket Assembly.8S2291 or FT887 Timing Pin.8S2243 Wrench.8S2244 Extractor.

NOTE: To check total rack travel after each pump is installed, the fuel pump housing must be removed from the engine and the governor removed from the fuel pump housing.

The fuel rack must be at the center position while removing or installing a fuel injection pump.

To center the rack, remove rack cover and pull rack to the full fuel-off position. With a small screwdriver, slide the rack toward the governor end of the housing until centering slot cut in the rack is beyond centering pin hole. Insert timing pin. Move rack to the full fuel-on position. The rack is now centered.

Use 8S2243 Wrench and 8S2244 Extractor to remove or install fuel injection pumps.

When removing fuel injection pumps and lifters, keep components together and identified so they can be installed in their respective location.

While disassembling fuel injection pumps, exercise considerable care to prevent damage to the plunger surfaces. The barrel and plunger assembly are matched and the individual parts are not interchangeable with other barrel or plunger assemblies. Use extreme care when inserting the plunger into the bore of the barrel.

To install, sight down the pump and align notches in bonnet and barrel with pump gear segment center tooth. Install the pump in the pump housing so the notches in bonnet and barrel align with dowels in the housing, and the pump gear segment center tooth aligns with the center notch of the fuel rack. Keep a downward force (by hand) on the pump and install bushing finger-tight, until top of threads are flush with top of housing. If the bushing can not be assembled this far finger-tight, remove the pump. Align components and install again. Tighten the retaining bushing to 100 ± 10 lb. ft. (13.8 ± 1.4 mkg). With less torque the pump will leak. If the torque is greater, the housing can be damaged.

To check for correct pump installation, check total rack travel after each pump is installed. Total rack travel should be approximately .624 in. (15.85 mm). A pump installed one tooth off in either direction will reduce rack travel approximately .100 in. (2.54 mm).

CHECKING RACK TRAVEL
1. 8S2291 or FT887 Timing Pin. 2. 3S3269 Contact Point. 3. 8S2283 Dial Indicator. 4. 9S225 Bracket Assembly.

NOTE: To check total rack travel, remove timing pin (1).

Removing And Installing Fuel Injection Pumps (On Engine)

To remove or install a fuel injection pump or pumps, the fuel rack must be centered. To center the fuel rack, remove the rack cover and move the governor control lever to the shut off position. Install timing pin (1) through hole (2) and in the slot cut in the fuel rack. Move the governor control lever in the fuel on direction until the slot in the fuel rack is against the timing pin. The fuel rack is now centered.

NOTE: The governor control lever must be secured in the FUEL ON direction so the fuel rack will be held in the centered position while removing or installing an injection pump.

CENTERING THE RACK
1. Timing pin. 2. Centering hole.

To remove or install the fuel injection pumps with the fuel injection pump housing and governor on the engine use the 5P1668 Wrench.

To remove a pump or pumps, use the following procedure:

1. Center the fuel rack.

REMOVING RETAINING BUSHING
3. 5P1668 Wrench.

2. Remove the fuel line from the pump to be removed.

3. Use the wrench (3) to remove the retaining bushing.

4. Install the 8S2244 Extractor on the pump and remove the pump from the housing.

To install a pump and/or pumps use, the following procedure:

1. Center the fuel rack.

2. Install the 8S2244 Extractor on the pump and align notches in bonnet and barrel with pump gear segment center tooth.

ALIGNING NOTCHES IN BONNET AND BARREL WITH PUMP GEAR SEGMENT CENTER TOOTH

3. Install the pump in the pump housing so the notches in the bonnet and barrel align with the dowels in the housing, and the pump gear segment center tooth aligns with the center notch of the fuel rack.

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NOTICE

Use extreme care to assure that the pump gear segment center tooth aligns with the center notch of the fuel rack.

4. Install the seal and retaining bushing. Apply a downward force (by hand) to the extractor and tighten the retaining bushing by hand (finger tight only) until the top of the bushing threads are flush with the top of the housing. If the bushing can not be assembled this far, finger-tight, remove the pump, realign components and install again.

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NOTICE

Do not force the top of the bushing threads flush with the top of the housing by using a wrench. If the pump is installed correctly, retaining bushing can be finger-tightened this far.

5. Tighten the retaining bushing to 100 ± 10 lb. ft. (13.8 ± 1.4 mkg).

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If one or more of the fuel injection pumps have been installed wrong, damage to the engine is possible if precautions are not taken at initial startup. When the fuel injection pumps have been removed and installed with the fuel injection pump housing on engine, take the following precautions during initial startup.

a. Remove the air cleaner leaving the air inlet pipe accessible as shown.

AIR INLET PIPE

b. If a pump has been installed wrong and the engine operates erratic, place a 6 in. (152 mm) square steel plate .375 in. (9.53 mm) thick over the air inlet opening as shown to stop the engine.

STOPPING THE ENGINE

6. If the engine operated erratically, remove the pump and repeat Steps 1 thru 5.

Fuel Pump Timing Dimension Setting-Off Engine

Engines Equipped With "Max-Min" Governor

6F6922 Depth Micrometer8S2273 or 8S7167 Gauge8S2280 Pointer Assembly1F8747 Timing Plate Assembly1B3680 Bolt3F1417 Washer8S2272 Shaft8S2291 or FT887 Timing Pin

The timing dimension should be checked to compensate for wear in the timing gears or lifters. This will assure that the point of the fuel injection is correct. If the timing dimension is too small, injection will begin early, and, if too great, injection will be late.

The fuel injection pump must be removed from the engine to check or adjust the timing dimension. Before removing the fuel injection pump housing, position No.1 piston at top center, see the topic, LOCATING TOP CENTER COMPRESSION POSITION FOR NO.1 PISTON.

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NOTICE

Do not rotate the engine crankshaft with the fuel injection pump and governor removed from the engine, unless front cover and timing advance have been removed. Without the support of the fuel injection pump camshaft bearing, the timing advance gear may wedge between the fuel pump drive gear on the engine camshaft and the engine front cover. This wedging action may cause the engine camshaft drive gear key to shear when the engine crankshaft is rotated.

1. Install the pointer assembly (3) on the fuel pump housing and slide the plate assembly (4) over the 8S2272 Shaft.

2. Assemble the shaft over the end of the fuel pump camshaft and secure it with the 1B3680 Bolt (3/8 in. - 24NF, 3-3/4 in. long) and a 3F1417 Washer. Do not tighten the bolt.

3. Install the timing pin through the fuel pump housing into the timing slot in the camshaft.

4. Position the timing plate (4) with the 0° mark aligned with the pointer assembly (3). Tighten bolt (5) to secure the timing plate to the fuel pump camshaft and REMOVE THE TIMING PIN.

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NOTICE

Do not turn the camshaft with the timing pin installed.

5. Turn the timing plate clockwise until the degree setting for the pump to be checked aligns with the pointer assembly. The pumps are numbered 1 thru 8 from the front (timing plate end) to the rear (governor end). The firing order is 1, 2, 7, 3, 4, 5, 6, 8.

6. With the timing plate indexed to the correct degree setting for the pump to be checked, install the gauge (2) into the pump bore.

7. Install depth micrometer (1) through the gauge and measure the timing dimension (A). This dimension should be within the limits listed in the chart.

TIMING FIXTURE GROUP INSTALLED
1. 6F6922 Depth Micrometer. 2. 8S2273 or 8S7167 Gauge. 3. 8S2280 Pointer Assembly. 4. 1F8747 Timing Plate Assembly. 5. Bolt.

CHECKING TIMING DIMENSION
1. 6F6922 Depth Micrometer, 4 to 5 in. (101.6 to 127.0 mm) 2. 8S2273 or 8S7167 Gauge. 6. Timing washer. The timing dimension is indicated by "A".

8. If the timing dimension is not within the specified limits, adjust it by replacing the timing washer (6) with one of a different thickness. Replacement washers are available in .003 in. (0.08 mm) increments from .088 in. (2.24 mm) thru .109 in. (2.77 mm) thick.

The part number and thickness are marked on the replacement washers.

9. Repeat the procedure for each pump.

10. Install the pumps in the fuel pump housing. See covering topic.

11. Install the fuel pump housing and all related components, that were removed, on the engine.

12. Time the fuel pump camshaft to the engine. See the covering topic.

Checking Fuel Injection Pump Timing Washer and Pump Plunger

When pump plunger wear becomes excessive, the timing washer may also be worn so it will not make full contact with the end of a new plunger. To avoid rapid wear on the end of the new plunger, replace the timing washers showing visible wear.

Removing And Installing Fuel Injection Pumps

Engines Equipped with "Max-Min" Governor

8S2305 Rack Position Tool Group8S2283 Dial Indicator8S2243 Wrench8S2244 Extractor

The fuel rack must be at the center or "zero" position while removing or installing a fuel injection pump. To center or "zero" the rack remove plug (1) from governor housing.

PLUG LOCATION
1. Plug.

Position the 8S2305 Rack Positioning Tool Group into hole for plug (1). Thread adapter (3) into the hole. Thread rod assembly (4) into the rack. Move the rod assembly and rack to full fuel-on position. Set the dial indicator (2) to .220 in. (5.59 mm) for 4.1 in. (104.1 mm) and 4.5 in. (114.3 mm) stroke engines and set indicator to .270 in. (6.86 mm) for 5.0 in. (127.0 mm) stroke engine. Move rod assembly and rack in the fuel-off direction until indicator is "zeroed." Rack is now centered.

CENTERING RACK
2. 8S2283 Dial Indicator. 3. 8S2314 Adapter. 4. 8S2311 Rod Assembly.

Use 8S2243 Wrench and 8S2244 Extractor to remove or install fuel injection pumps.

When removing fuel injection pumps and lifters, keep components together and marked so they can be installed in their respective location.

While disassembling fuel injection pump, exercise considerable care to prevent damage to the plunger surfaces. The barrel and plunger assembly are matched and the individual parts are not interchangeable with other barrel or plunger assemblies. Use extreme care when inserting the plunger into the bore of the barrel.

To install the pump, sight down the pump and align notches in bonnet and barrel with pump gear segment center tooth. Install the pump in the pump housing so the notches in bonnet and barrel align with dowels in the housing, and the pump gear segment center tooth aligns with the center notch of the fuel rack. Keep a downward force (by hand) on the pump and install bushing finger-tight until top of threads are flush with top of housing. If the bushing can not be assembled this far finger-tight, remove the pump. Align components and install again. Tighten the retaining bushing to 100 ± 10 lb. ft. (13.8 ± 1.4 mkg). With less torque the pump will leak. If the torque is greater, the housing can be damaged.

To check for correct pump installation, check total rack travel after each pump is installed. This requires a special procedure because the governor has a built in stop in the fuel-off direction which limits rack travel to .220 in. (5.59 mm). To check total rack travel remove the governor inspection cover, remove cotter pin (6) from the rack dowel and lift governor link (5) off the dowel. This makes total rack travel possible for checking correct pump installation.

REMOVING GOVERNOR LINK
5. Governor Link. 6. Cotter Pin.

Total rack travel should be approximately .532 in. (13.51 mm) for 4.1 in. (104.1 mm) and 4.5 in. (114.3 mm) stroke engines and approximately .582 in. (14.78 mm) for 5.0 in. (127.0 mm) stroke engine. A pump installed one tooth off in either direction will reduce rack travel approximately .100 in. (2.54 mm).

Hydraulic Governor Adjustments

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NOTICE

The high and low idle rpm and the rack setting values are incorporated in the RACK SETTING INFORMATION book. Only competent personnel should attempt to adjust these settings.

Checking Balance Point Rack Contact

The contact arrangement makes it possible to determine full load speed (governor balance point) during normal engine operation without removing the governor cover.

TERMINAL LOCATION
1. Brass screw terminal.

To check the balance point use a tachometer (known to be accurate) and an 8S4627 Circuit Tester. Connect one lead from the tester to the brass screw terminal (1) on governor cover and ground the other lead to the engine. Run the engine at high idle and slowly apply load while holding the governor control in the full fuel-on position.

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NOTICE

To accurately determine FULL LOAD speed, engine load must be increased slowly.

As engine speed decreases the circuit tester light should just barely light. It should not glow brightly. This indicates that the rack collar adjusting screw is making contact with the torque spring or rack stop. The engine speed at which contact is made is the full load speed.

NOTE: See RACK SETTING INFORMATION for FULL LOAD speed.

When engine speed does not correspond to the specified FULL LOAD SPEED, adjust the high idle setting. FULL LOAD SPEED will increase or decrease about the same amount that the HIGH IDLE SPEED is increased or decreased.

High and Low Idle RPM

The high idle adjustment screw is located inside the governor cover. It is necessary to break the governor seal and remove the cover before making a high idle adjustment. Since the stop collar is held in its axial position by the governor cover, some means must be provided to prevent the collar from turning during high idle adjustment. One method is to use the "drip pan" described in the topic CHECKING RACK SETTING WHILE ENGINE IS IN OPERATION.

ADJUSTMENT SCREWS
1. High idle adjustment screw. 2. Low idle adjustment screw.

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NOTICE

Remove the oil filler cap to reduce crankcase pressure.

See RACK SETTING INFORMATION for high and low idle specifications.

To increase high idle speed, turn adjustment screw counterclockwise.

LOW IDLE ADJUSTMENT SCREW (Later Governor)
2. Low idle adjustment screw.

To increase low idle speed on earlier governors, turn adjustment screw clockwise.

To increase low idle speed on later governors, turn adjustment screw in.

Checking and Adjusting Fuel Rack Setting

9S228 Rack Position Tool Group. (Part of9S240 Rack Positioning Tool Group).8S4627 Circuit Tester.8S2291 or FT887 Timing Pin.

The fuel rack setting can be checked and adjusted with the fuel injection pump housing either on or off the engine. The rack setting is based on the distance the rack travels from the "centered" position to the point where the stop collar adjustment screw touches the torque spring. This "centered" position is used to zero the rack or rack stop setting tool.

NOTE: The governor rear cover is protected with a tamper-proof seal. Install a new seal after each governor adjustment.

1. Remove the governor rear cover.

NOTE: To obtain the "zero" rack position mentioned in Step 3, it may be necessary on some engines to rotate stop collar (3) 90° to prevent adjustment screw (6) from contacting the torque spring or rack stop.

2. To center the fuel rack, remove the fuel rack cover and move the governor lever to shut-off position. Install timing pin (1) through hole (2) and into the slot cut in the fuel rack.

CENTERING THE RACK
1. Timing pin. 2. Centering hole.

ADJUSTMENT SCREWS (Typical Example)
3. Stop collar. 4. High idle adjustment screw. 5. Torque spring or rack stop. 6. Stop collar adjustment screw. 7. Low idle adjustment screw.

3. Install the rack positioning tool group. Move the governor control lever slowly in the fuel-on direction until the first significant resistance is felt, then zero the dial indicator.

NOTE: To "zero" the indicator, move the dial indicator back and forth within the mounting bracket until the red zero and black zero on the revolution counter are centered. Tighten the dial indicator retaining bolt. Now place the zero on the large dial face under the large hand by rotating the dial face.

4. Release the governor lever. Remove the timing pin. Turn stop collar (3) to align adjustment screw (6) with torque spring or rack stop (5).

INSTALLING 9S228 RACK POSITION TOOL GROUP (Typical Example)

5. Attach the alligator clip end of the 8S4627 Circuit Tester to the torque spring or rack stop and insert the pin end of the tester into one of the governor cover bolt holes.

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NOTICE

The torque spring or rack stop is insulated from the governor housing. Be sure the alligator clip on the tester touches only the torque spring or rack stop.

ADJUSTING FUEL RACK (Typical Example)

6. Move the stop collar forward until the stop collar adjustment screw just touches the torque spring or rack stop. The tester light should just barely light. It should not glow brightly. The dial indicates the rack setting reading.

7. If adjustment is needed, loosen the lock nut and turn stop collar adjustment screw (6) with a 4B9820 Wrench (.125 in. hex). Repeat the checking procedure, then tighten lock nut to 11 ± 1 lb. ft. (1.5 ± 0.14 mkg).

Checking Rack Setting While Engine is in Operation

It is possible to check rack position while the engine is running. This helps determine both the actual horsepower output and the cause of 'lack of power' complaints. Setup must be done prior to engine startup.

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NOTICE

Do not attempt to adjust the rack while the engine is in operation.

1. Since oil is present in the hydraulic governor while the engine is running, some means must be provided to catch the oil. Cut off the upper half of a spare governor housing cover; thus providing a "drip pan" to bolt on the governor housing. Align boss (1) with slot (2) in the rack stop collar. This prevents the stop collar from turning.

INSTALLING "DRIP PAN" (Typical Example)
1. Boss. 2. Slot in rack stop collar.

2. Remove the oil filler cap.

CHECKING RACK SETTING (Typical Example)

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NOTICE

The direct injection engine has a tendency to build up crankcase pressure. With the 'half' governor cover, the crankcase is open to atmosphere and oil could flow out at a rapid rate. This oil loss could damage the engine and create a fire hazard. Removing the oil filler cap reduces crankcase pressure.

3. Install the 9S228 Rack Position Tool Group. Start the engine and measure total rack movement.

Hydraulic Governor Linkage Adjustment

Earlier Governor

1P2385 Protractor Assembly.

With governor at LOW IDLE position, install lever (3) at a 20° angle (2) to the rear face of the governor. Face (5) of lever (3) that contacts low idle adjusting screw (4) to be parallel to rear face of governor. Tighten bolt and nut (1) to 23 ± 2 lb. ft. (3.2 ± 0.3 mkg). Adjust remaining linkage to lever (3).

At FULL LOAD the degree of lever (3) operating range varies from engine to engine. In all instances, governor linkage adjustment must be sufficient enough to assure full travel of lever (3).

GOVERNOR LINKAGE ADJUSTMENT (Typical Example)
1. Bolt and nut. 2. 20° angle to the rear face of governor. 3. Governor lever. 4. Low idle adjusting screw. 5. Face of governor lever (3) that contacts low idle adjusting screw.

Later Governor

1P2385 Protractor Assembly.

With governor at LOW IDLE position, install lever (3) at 20° angle (2) to the rear face of the governor with use of the 1P2385 Protractor Assembly. Face (5) of lever (3) must be parallel to rear face of governor. Tighten bolt and nut (1) to 23 ± 2 lb. ft. (3.2 ± 0.3 mkg). Adjust remaining linkage to lever (3).

At FULL LOAD the degree of lever (3) operating range varies from engine to engine. In all instances, governor linkage adjustment must be sufficient enough to assure full travel of lever (3).

1P2385 PROTRACTOR TOOL USAGE
A-Angle setting indicator. B-Protractor plate edge aligned with lever. C-Vertical housing face and extension arm alignment. D-Level bubble. E-Angle setting indicator. F-Extension arm aligned with lever. G-Extension arm aligned with lever. H-Plate edge aligned with second lever. I-Angle setting indicator.

Max-Min Governor Adjustments

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NOTICE

The high and low idle rpm and the rack setting values are incorporated in the RACK SETTING INFORMATION book. Only competent personnel should attempt to adjust these settings.

High and Low Idle RPM

Check the engine rpm with an accurate tachometer. Install the tachometer on the adapter (1) located on the front cover. The reading taken at this point, with a 1:1 tachometer, will be one-half engine rpm.

ADAPTER LOCATION
1. Adapter.

Remove the high idle adjustment screw cover from the rear of the governor. Turn the high idle adjusting screw (2) clockwise to increase or counterclockwise to decrease high idle speed.

HIGH IDLE ADJUSTMENT
2. High idle adjusting screw.

NOTE: If the adjusting screw requires alignment to install the cover, turn the screw in a clockwise direction the minimum distance required for installation.

LOW SPEED ADJUSTMENT
3. Low idle stop. 4. Locknut.

Adjust low idle speed by loosening locknut (4) and turning the adjustable stop (3). Turning the stop "in" decreases and "out" increases the low idle speed. Tighten the locknut and recheck the adjustment.

Checking and Adjusting Fuel Rack Setting

1. Remove plug (1) from governor housing.

PLUG LOCATION
1. Plug.

2. Position the 8S2305 Rack Positioning Group into the rack cap hole. Thread adapter (2) into the hole.

INSTALLING 8S2305 RACK POSITIONING GROUP
2. 8S2314 Adapter. 3. 8S2311 Rod Assembly.

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NOTICE

Do not overtighten the adapter or plug. The governor housing is made of aluminum and excessive tightening will strip the threads.

3. Thread the rod assembly (3) into the rack.

4. Disconnect external throttle linkage, and rotate governor control to its full travel limit in the 'increase power' direction. A 25 lb. in. (28.82 cm.kg) torque pull will assure full travel. Push the rod assembly (3) forward.

5. Set the dial indicator (4) to the following:

.220 in. (5.59 mm) for 4.1 in. (104.1 mm) and 4.5 in. (114.3 mm) stroke engines.

.270 in. (6.85 mm) for the 5.0 in. (127.0 mm) stroke engine.

CHECKING FUEL RACK SETTING
3. 8S2311 Rod Assembly. 4. 8S2283 Dial Indicator.

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NOTICE

The 8S2283 Dial Indicator is calibrated for this procedure. Do not use conventional indicators.

6. With the governor control held in its full travel limit, read the rack setting while pulling back on the rod assembly (3) with a 10 to 15 pound (4.5 to 6.8 kg) pull.

7. On governors without torque springs [5.0 in. (127.0 mm) stroke engine], the dial indicator reading is the rack setting value and should agree with the published specifications. See the RACK SETTING INFORMATION book. On governors with torque springs [4.1 and 4.5 in. (104.1 and 114.3 mm) stroke engines] the dial indicator reading is approximately .005 in. (0.13 mm) greater than the rated rack setting value.

8. If the fuel rack adjustment needs to be changed, remove the high idle adjustment screw cover (5).

HIGH IDLE ADJUSTMENT SCREW
5. Cover

NOTE: Be sure the 8S2305 Rack Positioning Group is correctly installed and the dial indicator is adjusted to the proper value as described in Steps 1 thru 5.

9. Move the governor control linkage to the FULL ON position. Secure the linkage in this position with tag wire.

10. Loosen the locknut on rack adjusting screw (6).

11. While pulling the rod assembly (3) and rack toward the shut-off position, turn the rack adjusting screw (6) to obtain the correct rack setting value on the dial indicator.

ADJUSTING FUEL RACK
3. 8S2311 Rod Assembly. 6. Rack adjusting screw.

12. Tighten the adjusting screw locknut and recheck the setting.

13. Remove the tag wire securing the governor control linkage in the full on position. Be sure the linkage operates smoothly.

14. Remove the 8S2305 Rack Positioning Group and install the cover. Reseal the governor.

Max-min Governor Linkage Adjustment

Correct initial setting of the max-min governor terminal lever is necessary to obtain full rack. With engine operating in low idle, adjust the lever (1) so the face that contacts the low idle adjusting screw (4) is parallel to the rear face of the governor. The lever assembly (2) is then installed at a 14° angle to the rear face of the governor.

TERMINAL-LEVER LOW IDLE
1. Governor terminal lever. 2. Lever assembly. 3. Triangle. The lever assembly angle can be checked using a triangle of the dimensions shown. 4. Low idle adjusting screw.

TERMINAL LEVER-FULL LOAD
5. Tapped hole. Insert a 1/4"-28 bolt here to hold lever in full load position. When measuring degree of rotation, use a triangle of dimensions shown.

With terminal lever correctly assembled and adjusted, a 32° operating range is required to insure full rack movement. To check, rotate lever assembly to full load position (just beyond the tapped hole in the governor cover). Measure the degree of rotation from low idle to full load.

Cylinder Head And Valves

Compression

Irregular (rough) engine operation can be caused by improperly adjusted or leaky valves. Operate the engine at the rpm that makes the malfunction most pronounced. A non-firing or low compression cylinder can be located by momentarily loosening and then retightening fuel lines, one at a time, at an injection pump. Continue this until a loosened fuel line makes little or no difference in engine operation. This same check can also indicate faulty fuel injection, so further checking of the cylinder is necessary.

The preceding test is merely a quick means of locating the source of cylinder compression loss. Removal of the head and visual inspection of the valves and valve seats is necessary to check for minor valve defects that do not have much effect on engine operation. This is usually done during general engine reconditioning.

Checking Valve Lash Adjustment

Check valve lash adjustment within the first 3020 miles and every 24,000 miles thereafter. Check valve lash adjustment every six months regardless of miles.

To check and adjust valve lash, use the following procedure:

1. Remove the valve covers.

2. Rotate the crankshaft CLOCKWISE (as viewed from the front of the engine) until No.1 piston is at top center on the compression stroke. The TDC-1 mark on the damper should align with the timing pointer.

3. Adjust the intake and exhaust valve lash for cylinders No.1 and No.2. Loosen locknut (1) and adjust valve lash with adjusting screw (2).

4. After adjustment is complete, hold adjusting screw (2) and tighten locknut (1) to 24 ± 5 lb. ft. (3.3 ± 0.7 mkg). Recheck the adjustment.

5. Rotate the crankshaft 180° CLOCKWISE (as viewed from the front of the engine). The VS mark on the damper should align with the timing pointer. Adjust the intake and exhaust valve lash for cylinders No.7 and No.3.

NOTE: Engines that do not have the VS mark stamped on the damper or pulley should be marked with chalk 180° from the TDC-1 mark.

ADJUSTING VALVE LASH
1. Locknut. 2. Adjusting screw.

6. Rotate the crankshaft 180° CLOCKWISE (as viewed from the front of the engine). The TDC-1 mark on the damper should align with the timing pointer. Adjust the intake and exhaust valve lash for cylinders No.4 and No.5

TIGHTENING LOCKNUT

7. Rotate the crankshaft 180° CLOCKWISE (as viewed from the front of the engine). the VS mark on the damper should align with the timing pointer. Adjust the intake and exhaust valve lash for cylinders No.6 and No.8.

CYLINDER AND VALVE LOCATION

Frequent need for valve lash adjustment may indicate unusual wear elsewhere in the engine, and should be investigated and corrected to prevent more serious engine damage.

Insufficient lash, if not corrected, may cause rapid wear of the camshaft and cam followers. Rapid valve lash closeup may indicate valve seat recession. Causes of valve seat recession include defective fuel nozzles, continuous operation in a lug condition, partially blocked air inlet or dirty air filters, high rack setting, or engine misapplication.

Excessive lash will cause undue stress throughout the valve train. If not corrected, excessive lash may result in broken valve stems, push rods, or spring retainers. Rapid valve lash increase may indicate camshaft and cam follower wear, rocker arm anvil wear, bent pushrods, lash adjusting screw backing out (locknut not tightened) or breakage of the socket on the upper end of the push rod.

Rapid wear of the camshaft and cam followers is usually a sign of oil contamination, and repair should include an investigation for fuel dilution or dirt in the lubricating oil.

Procedure For Measuring Camshaft Lobes

To measure height (B) of camshaft lobes, use the following procedures:

1. Measure base circle (C) of one exhaust and one intake lobe. Record each dimension.

2. Add lobe lift dimension (A) to each base circle measurement. The lobe lift dimension (A) is .3071 in. (7.800 mm) for the exhaust lobe and .3077 in. (7.816 mm) for the intake lobe.

3. The minimum height of lobe (B) is .025 in. (0.64 mm) less than the dimension found in Step 2.

Example of finding the height of a lobe:

CAMSHAFT LOBE
A. Lobe lift. B. Lobe height. C. Base circle.

Cooling System

The cooling system is pressurized, pump inlet-regulated, and equipped with a shunt line.

Pressurizing the cooling system permits safe operation at coolant temperature higher than the normal boiling point and reduces the possibility of air or steam pockets forming in the coolant passages. Pump inlet-regulation makes it possible to maintain positive temperature control. The shunt line prevents cavitation by maintaining a positive, static head of water at the pump inlet at all times.

Many times, overheating of the engine is caused by failure to make simple systematic inspections. Visual inspections should be made before instrumentation testing.

Visual Inspection

1. Check coolant level.

2. Inspect for leaks in the system.

3. Inspect the radiator fins. Be certain the air flow through the radiator is not restricted by trash or bent radiator fins.

4. Check fan belts.

5. Check for damaged fan blades.

6. Observe if there is any air or combustion gas in the cooling system.

7. Check to see that the pressure cap sealing surfaces are clean.

Testing Cooling System

Remember that temperature and pressure go hand-in-hand and neither one can be tested logically without considering the other. For example, the effect of pressurization and altitude on the boiling point of water is shown in the chart.

Cooling System Test Tools

9S9102 Thermistor Thermometer Group9S7373 Air Meter Group1P5500 Portable Phototach Group9S8140 Cooling System Pressurizing Pump Group

To test the cooling system if heating and loss of coolant is a problem use the testing tools.

The 9S9102 Thermistor Thermometer Group is used in the diagnosis of heating problems. The testing procedure is in Special Instruction (GMG00450).

9S9102 THERMISTOR THERMOMETER GROUP

The 9S7373 Air Meter Group is used to check the air flow through the radiator core. The testing procedure is in Special Instruction (GMG00203).

9S7373 AIR METER GROUP

The 1P5500 Portable Phototach Group is used to check the fan speed. The testing procedure is in Special Instruction (GMG00819).

1P5500 PORTABLE PHOTOTACH GROUP

The 9S8140 Cooling System Pressurizing Pump Group is used to test pressure caps and pressure relief valves, and to pressure check the cooling system for leaks.

9S8140 COOLING SYSTEM PRESSURIZING PUMP GROUP

Temperature Gauge

9S9102 Thermistor Thermometer Group

If overheating and loss of coolant is a problem, a pressure loss in the system could be the cause. If an overheating condition is indicated on the temperature gauge and loss of coolant is not evident, check the accuracy of the temperature gauge. Make this check by connecting the 9S9102 Thermistor Thermometer Group to the front cover.

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Take special care when working around an engine if it is running.

9S9102 THERMISTOR THERMOMETER GROUP INSTALLED

Start the engine. Cover the radiator to reduce air flow and cooling. The instrument panel temperature gauge should register a comparable temperature to that indicated by the 9S9102 Thermistor Thermometer Group.

Pressure Cap

If the pressure check indicates that the system is unable to hold pressure, the source of the pressure leak must be determined. One of the causes of cooling system pressure loss can be a faulty pressure cap seal. Inspect the pressure cap carefully for possible damage to the seal or sealing surfaces. The build-up of deposits on the cap, seal and filler neck should be removed.

Water Temperature Regulator (Thermostat)

The opening temperature of thermostats (bench test in atmospheric pressure) should be as listed in the following charts.

1. Remove the thermostats from the front cover.

2. Suspend the thermostats and a thermometer in a pan of water.

3. Apply heat to the pan and stir the water to maintain uniformity.

4. Observe the opening temperature of the thermostats.

If a thermostat does not operate correctly, install a new thermostat.

Water Pump Pressure Check

9S8138 Pressure Gauge3B7722 Bushing

The pressure at the water pump outlet determines if the shunt system and water pump are operating properly. To check the pump pressure install the pressure gauge (2) in the front cover as shown. The pressure should be a minimum of 15 psi (1.05 kg/cm²) at 2800 rpm on all engines.

GAUGE INSTALLED
1. 3B7722 Bushing. 2. 9S8138 Pressure Gauge.

If pump pressure does not meet the minimum pressure: First, check the vent tube between the radiator top tank and the expansion tank; it should have an inside diameter of approximately .19 in. (4.8 mm). Second, check to see that the shunt line has a minimum inside diameter of .75 in. (19.1 mm).

Inspect Rebuilt Water Pumps

Individual parts for the water pump are not serviced. However, some firms may be rebuilding these pumps, using a different impeller, or one which they have machined on the seal face or on the vanes.

Unless the same impeller or one identical to it is used and positioned on the shaft within the specifications, a rebuilt pump may not produce sufficient water flow for adequate cooling. If the rebuilder used an impeller design different from the original equipment pump, he should be asked to guarantee that his rebuilt pump output meets new pump requirements.

Here is how to check a rebuilt pump:

1. Bearing end clearance should be .001 to .025 in. (0.03 to 0.64 mm).

2. The clearance (2) between the impeller face and the front cover is .005 to .045 in. (0.13 to 1.14 mm).

This clearance indicates the condition of the impeller and its location on the shaft. The bearing and front cover condition are also indicated. Check impeller clearance as follows:

IMPELLER CLEARANCE AND HEIGHT
1. Front cover. 2. Impeller clearance. 3. Impeller. 4. Impeller height [1.370 to 1.400 (34.80 to 35.60 mm)].

a. Place a small ball of clay or wax on two impeller vanes directly opposite each other.

b. Using a new gasket, install the pump and tighten the mounting bolts. Do not turn the pulley.

c. Push in on the pulley with a force of about 15 pounds (7 kg) to remove end clearance.

d. Remove pump and measure thickness of clay or wax compressed between the vanes and cover face. When the last bolts are removed, be careful not to disturb the clay or wax. The impeller clearance thickness should be .005 to .045 in. (0.13 to 1.14 mm).

REMOVING END CLEARANCE

Dynamometer Test Precaution

To avoid possible engine damage while testing on a dynamometer, the thermostats must be installed and the shunt line (2) connected as shown.

SHUNT LINE CONNECTED TO ENGINE
1. FT790 Cooling Tower Group. 2. Shunt line.

Electrical System

Use a DC voltmeter to locate starting system components that do not function.

Turn the starter switch to "Start." Starter motor solenoid is audible as the starter motor pinion engages the engine flywheel. The solenoid operation should also close the electric circuit to the motor.

Attach one voltmeter lead to the solenoid terminal that is connected to the motor. Ground the other lead. Turn the Starter Switch to "Start" and observe the voltmeter. A battery voltage reading indicates the malfunction is in the motor. No voltmeter reading indicates that the solenoid contacts do not close and the solenoid must be repaired. It could also indicate that starter pinion clearance needs adjustment.

A starting motor solenoid that will not operate may not be receiving battery current. Attach one voltmeter lead to the solenoid battery cable connection. Ground the other lead. No voltmeter reading indicates a defective solenoid switch.

Attach one voltmeter lead to the starter switch battery wire terminal and ground the other lead. A voltmeter reading indicates a defective switch.

A starting motor that operates too slowly can be overloaded by excessive mechanical friction within the engine. Slow starting motors can also be the result of shorts, loose connections, and/or excessive dirt within the motor.

Pinion Clearance Adjustment

Whenever the solenoid is installed, the pinion clearance should be adjusted. The adjustment should be made with the starting motor removed. Bench test and adjust the pinion clearance at installation of solenoid as follows:

1. Install the solenoid without connector from the MOTOR terminal on solenoid to the motor.

2. Connect a battery, of the same voltage as the solenoid, to the terminal (2).

CONNECTIONS FOR CHECKING PINION CLEARANCE
1. Connector from MOTOR terminal on solenoid to motor. 2. SW terminal. 3. Ground terminal.

3. Connect the other side of battery to ground terminal or to solenoid frame.

4. MOMENTARILY flash a jumper wire from the solenoid terminal marked MOTOR to the frame or ground terminal. The pinion will shift into cranking position and will remain there until the battery is disconnected.

5. Push pinion towards commutator end to eliminate free movement.

CIRCUIT FOR ADJUSTING PINION CLEARANCE
2. SW terminal. 3. Ground terminal. 4. Ground flashing point.

6. Pinion clearance should be .36 in. (9.1 mm).

7. Adjust clearance by removing plug and turning shaft nut.

PINION CLEARANCE ADJUSTMENT
5. Pinion. 6. Pinion clearance. 7. Shaft nut.

Allison Automatic Transmission

Linkage Adjustment

Adjust selector lever in the operators compartment and selector lever on transmission so stops in the shift tower match detents in transmission.

Adjust linkage between governor and transmission throttle valve so transmission upshift is approximately 50 rpm below engine full load speed. Check this adjustment anytime shifting feels erratic or the transmission is automatically upshifting or downshifting too soon.

NOTE: See Rack Setting Information for engine full load speed.

Hydraulic Retarder Linkage

Adjust as necessary so retarder valve travels a full 1/2 in. (12.7 mm) toward the rear, just before the retarder pedal hits the stop. When pedal is released, the retarder valve must travel 1/2 in. (12.7 mm) to the forward stop.

For information regarding transmission adjustment or repair, refer to Allison or Truck Manufacturer literature or personnel.