Testing And Adjusting

Usage:

Introduction

NOTE: For Specifications with illustrations, make reference to Specifications For 3516 Generator Set Engines, SENR5132. If the Specifications in SENR5132 are not the same as in the Systems Operation, Testing And Adjusting, look at the printing date on the back cover of each book. Use the Specifications given in the book with the latest date.

Troubleshooting

Troubleshooting can be difficult. On the following pages there is a list of possible problems. To make a repair to a problem, make reference to the cause and correction.

This list of problems, causes and corrections, will only give an indication of where a possible problem can be, and what repairs are needed. Normally, more or other repair work is needed beyond the recommendation in the list.

Remember that a problem is not normally caused only by one part, but by the relation of one part with other parts. This list can not give all possible problems and corrections. The service personnel must find the problem and its source, then make the necessary repairs.

Troubleshooting Problem List

1. Engine Crankshaft Will Not Turn When Start Switch Is On.

2. Engine Will Not Start. Governor Terminal Shaft Does Not Move.

3. Engine Will Not Start. Governor Terminal Shaft Moves.

4. Engine Overspeeds On Start.

5. Engine Speed Does Not Have Stability.

6. Engine Misfiring Or Running Rough.

7. Engine Stall At Low RPM.

8. Not Enough Power.

9. Too Much Vibration.

10. Loud Combustion Noise.

11. Valve Train Noise (Clicking).

12. Oil In Cooling System.

13. Fuel In Cooling System.

14. Mechanical Noise (Knock) In Engine.

15. Fuel Consumption Too High.

16. Loud Valve Train Noise.

17. Too Much Valve Lash.

18. Valve Rotocoil Or Spring Lock Is Free.

19. Oil At The Exhaust.

20. Little Or No Valve Lash.

21. Engine Has Early Wear.

22. Coolant In Lubrication Oil.

23. Too Much Black Or Gray Smoke.

24. Too Much White Or Blue Smoke.

25. Engine Has Low Oil Pressure.

26. Engine Uses Too Much Lubrication Oil.

27. Engine Coolant Is Too Hot.

28. Alternator Gives No Charge.

29. Alternator Charge Rate Is Low Or Not Regular.

30. Alternator Charge Too High.

31. Alternator Has Noise.

32. Exhaust Temperature Too High.

33. Air Starter Motor Does Not Turn.

34. Air Starter Motor Turns Slowly Or Has A Loss Of Power.

35. Air Starter Motor Pinion Does Not Engage With The Flywheel.

36. Air Starter Motor Runs, Pinion Engages But Does Not Turn The Flywheel.

37. Air Starter Motor Pinion Does Not Engage Correctly With The Flywheel.

38. Electric Starter Motor Does Not Turn.

Troubleshooting Problems

Problem 1: Engine Crankshaft Will Not Turn When Start Switch Is On

Probable Cause:

1. Problem With Air Starter Motor

Make reference to Problem 33.

2. Problem With Electric Starter Motor

Make reference to Problem 38.

3. Problem With Engine Protective System

Make reference to Electric Protective System, SENR2984 or SENR2985, or make reference to Hydra Mechanical Protective System, SENR3078.

4. Inside Problem Prevents Engine Crankshaft From Turning

If the crankshaft can not be turned after disconnecting the driven equipment, remove the fuel injectors and check for fluid in the cylinders while turning the crankshaft. If fluid in the cylinders is not the problem, the engine must be disassembled to check for other inside problems. Some of these inside problems are bearing seizure, piston seizure, or valves making contact with the pistons.

Problem 2: Engine Will Not Start - Governor Terminal Shaft Does Not Move To Open Injector Racks

Probable Cause:

1. Too Much Binding In Control Linkage

Engine can start cold, but with hot oil, governor does not develop enough oil pressure to move linkage. Check linkage effort and correct.

2. No Signal To Actuator Solenoid

Make reference to 2301 Electric Governor, SENR2928.

3. Low Oil Pressure In Actuator

The actuator oil pump relief valve may be stuck open or leaking. Correct by governor disassembly and cleaning.

Problem 3: Engine Will Not Start - Governor Terminal Shaft Opens At Least Half Way Or More At Cranking As Observed By Outboard Shaft Rotation

Probable Cause:

1. Slow Cranking Speed

Make reference to Problem 29.

2. Low Quality Fuel Or Water In Fuel

Remove fuel from the tank, lines and fuel manifolds. Install new fuel filters and put a good grade of clean fuel in the fuel tank. Use priming pump to fill system with fuel and to remove air.

3. No Fuel To Injectors

Check fuel level in fuel tank and fill if necessary. Use priming pump to remove any air from the fuel system.

Install new fuel filters if necessary. Blocked or broken fuel lines should be cleaned or replaced. Check the fuel transfer pump for damage or wear and make replacements as needed.

Governor linkage not connected to internal rack linkage (such as improper assembly during overhaul). Make sure governor linkage is correctly engaged.

4. Fuel Pressure Is Low

At starting rpm, the minimum fuel pressure from fuel transfer pump must be 20 kPa (3 psi). If fuel pressure is less than 20 kPa (3 psi) change the fuel filters. Look for air in the fuel system. If fuel pressure is still low, check the fuel bypass valve and the fuel transfer pump for correct operation.

5. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

Problem 4: Engine Overspeeds On Start

Probable Cause:

1. Fuel Control Linkage

Improper assembly after overhaul, linkage not free, bound up in fuel-on position, governor output lever not connected to rack fork lever. Make repairs or replacements as needed.

2. Governor Or Actuator Problem

Make reference to 2301 Electric Governor, SENR2928.

Problem 5: Engine Speed Does Not Have Stability

Probable Cause:

1. Engine Misfiring

Make reference to Problem 6.

2. Linkage Is Binding, Or Worn With Flat Spots And High Clearances

Inspect and repair or replace linkage as needed.

3. Governor Problem

Make reference to 2301 Electric Governor, SENR2928.

Problem 6: Engine Misfiring Or Running Rough

Probable Cause:

1. Fuel Pressure Is Low

Make sure there is fuel in the fuel tank. Look for leaks or bad bends in the fuel line between fuel tank and fuel transfer pump. Look for air in the fuel system, sticking, binding or defective fuel bypass valve. Check fuel pressure. The outlet pressure of the fuel transfer pump must be a minimum of 415 kPa (60 psi) at full load speed. The pressure in both fuel manifolds must be 415 to 450 kPa (60 to 65 psi). If fuel pressure is lower than the above pressure, install new filters. If fuel pressure is still low, check the fuel transfer pump and fuel pressure regulator valve at the fuel manifold.

2. Air In Fuel System

Find the air leak in the fuel system and correct it. If air is in the fuel system, it will generally get in on the suction side of the fuel transfer pump.

3. Leak Or Break In Fuel Line Between Fuel Manifold And Cylinder Head

Install a new fuel line.

4. Defect In Fuel Injector(s)

Temperature of an exhaust manifold port, when the engine runs at low idle speed, can be an indication of the condition of a fuel injector. Low temperature at an exhaust manifold port is an indication of no fuel to the cylinder. This can possibly be an indication of an injector with a defect. Extra high temperature at an exhaust manifold port can be an indication of too much fuel to the cylinder, also caused by an injector with a defect.

5. Wrong Valve Lash

Make adjustment according to Subject, Valve Lash.

6. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

7. Bent Or Broken Push Rod

Replacement of push rod is necessary.

8. Fuel has "Cloud Point" Higher Than Atmospheric Temperature ("Cloud Point" = Temperature Which Makes Wax Form in Fuel)

Drain the fuel tank, lines and fuel manifolds. Change the fuel filter. Fill the tank with fuel which has the correct "cloud point", and remove the air from the system with the priming pump. In some installations it may be necessary to use the fuel heaters to insure proper fuel flow and to prevent filter blockage from fuel wax. The fuel temperature at which flow is reduced and filter blockage occurs is usually dependent upon the amount of wax in the fuel (its cloud point).

Problem 7: Engine Stall At Low RPM

Probable Cause:

1. Fuel Pressure Is Low

2. Idle RPM Too Low

Make adjustment to governor so idle rpm is the same as given in the Fuel Setting And Related Information Fiche.

3. Engine Accessories

Check engine accessories for damage and make repair or replacement. If necessary, disconnect the accessories and test the engine.

4. Defect In Fuel Injector(s)

Make Reference to Problem 6.

Problem 8: Not Enough Power

Probable Cause:

1. Dirty Fuel Filters

Install new fuel filters.

2. Low Quality Fuel Or Water In Fuel

Remove the fuel from the fuel tank. Install new fuel filters. Put a good grade of clean fuel in the fuel tank.

3. Fuel Viscosity Is Low

Measure the API fuel gravity. Refer to Special Instruction, GMG00977.

4. Fuel Temperature Is High

Excess fuel flow temperature should be 65.6 to 82.2°C (160 to 180°F). If excess fuel flow temperature exceeds 82.2°C (180°F), the use of a fuel cooler is recommended to prevent excessive engine power loss and to maintain an acceptable injector life.

5. Fuel Pressure Is Low

6. Defect In Fuel Injector

Make Reference to Problem 6.

7. Leaks In Air Inlet System

Check the pressure in the air inlet manifold. Look for restrictions in the air cleaner.

8. Actuator And Fuel Control Linkage

Make sure actuator is moving fuel control linkage against fuel setting stop. Make adjustment to get full travel of linkage. Install new parts for those that have damage or defects. If control linkage is not against stop and engine runs below rated speed under load, check high idle and adjust if necessary.

9. Wrong Valve Lash

Make adjustment according to subject, Valve Lash.

10. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

11. Fuel Setting Incorrect

Make an adjustment of the fuel setting. See Fuel Setting and Related Information Fiche for the correct fuel setting and Fuel Setting Procedure in Testing And Adjusting section.

12. Defect In Aftercooler

Check temperature of inlet and outlet coolant supply. Remove any external or internal restrictions.

13. Turbocharger Has Carbon Deposits Or Other Causes Of Friction

Make inspection and repair of turbocharger as necessary.

Problem 9: Too Much Vibration

Probable Cause:

1. Vibration Damper Loose

Check vibration damper for damage. Tighten bolts. If vibration damper bolt holes have damage or wear, replace with new parts.

2. Vibration Damper Has A Defect

Install a new vibration damper.

3. Engine Supports Are Loose, Wrong Or Have A Defect

Tighten all mounting bolts. Install new components if necessary.

4. Driven Equipment Is Not In Alignment Or Is Out Of Balance

Check alignment and balance, correct if needed.

5. Misfiring Or Running Rough

Make Reference to Problem 6.

Problem 10: Loud Combustion Noise

Probable Cause:

1. Low Quality Fuel

Remove the fuel from the fuel tank. Install new fuel filters. Put a good grade of clean fuel in the fuel tank.

2. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

3. Defect In Fuel Injector(s)

Make Reference to Problem 6.

4. Improper Valve Train Operation

Make reference to Problem 16, 17 and 18.

Problem 11: Valve Train Noise

Probable Cause:

1. Damage To Valve Spring(s), Locks, Or Broken Or Worn Valve Lifter

Install new parts where necessary. Broken locks can cause the valve to get into the cylinder. This will cause much damage.

2. Not Enough Lubrication

Check lubrication in valve compartment. There must be a strong flow of oil at engine high rpm, but only a small flow of oil at low rpm. Oil passages must be clean, especially those that send oil to the cylinder head.

3. Too Much Valve Lash

Make adjustment according to the subject, Valve Lash.

4. Damage To Valve(s)

Make a replacement of the valve(s) and make an adjustment as necessary.

5. Injector Plunger Stuck - Push Rod Out Of Position

Repair as needed.

6. Damaged Camshaft Lobe Or Valve Lifter

Make reference to Problem 16.

Problem 12: Oil In Cooling System

Probable Cause:

1. Defect In Core Of Engine Oil Cooler

Inspect each cooler and make a replacement or repair defective oil cooler.

2. Failure Of Cylinder Head Gasket Or Water Seals

Check cylinder liner projection. Install a new cylinder head gasket and new water seals in the spacer plate. Tighten the bolts that hold the cylinder head according to the Specifications.

Problem 13: Fuel In Cooling System

Probable Cause:

1. Internal Defect In Cylinder Head

Remove valve cover. Remove fuel supply and fuel return line from cylinder head. Cap fuel return connector and apply 700 kPa (100 psi) maximum air pressure to fuel supply connector. Check for fuel leakage around injector. If leakage is present, it will be necessary to remove injector and install a new O-ring seal.

Problem 14: Mechanical Noise (Knock) In Engine

Probable Cause:

1. Failure Of Bearing For Connecting Rod

Inspect the bearings for the connecting rods and the bearing surfaces (journals) on the crankshaft. Install new parts where necessary.

2. Damaged Gears

Install new parts where necessary.

3. Damaged Crankshaft

Make replacement of the crankshaft.

4. Defect In Accessory Equipment

Repair or install new components.

5. Damaged Camshaft Lobe

Make reference to Problem 16.

Problem 15: Fuel Consumption Too High

Probable Cause:

1. Fuel System Leaks

Tighten or make replacement of parts at points of leakage.

2. Fuel And Combustion Noise (Knock)

Make Reference to Problem 6 and Problem 10.

3. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

4. Defect In Fuel Injector(s)

Make Reference to Problem 6.

Problem 16: Loud Valve Train Noise

Probable Cause:

1. Damage To Valve Spring(s)

Make replacement of parts with damage.

2. Damage To Camshaft

Make replacement of parts with damage. Clean engine thoroughly. If replacement of camshaft is made, new valve lifters are also necessary.

3. Damage To Valve Lifter

Clean engine thoroughly. Make a replacement of the damaged valve lifters. Inspect camshaft lobes for damage. Look for valves that do not move freely. Make an adjustment to valve lash according to the subject, Valve Lash.

Problem 17: Too Much Valve Lash

Probable Cause:

1. Not Enough Lubrication

Check lubrication in valve compartment. There must be a strong flow of oil at engine high rpm, but only a small flow at low rpm. Oil passages must be clean, especially those sending oil to the cylinder head.

2. Rocker Arm Worn At Face That Makes Contact With Bridge

If there is too much wear, install new parts or rocker arms. Make adjustment of valve lash according to subject, Valve Lash.

3. Bridges For Valves Worn/Incorrect Adjustment

Make an adjustment or replacement as necessary.

4. End Of Valve Stem Worn

If there is too much wear, install new valves. Make adjustment to valve lash according to subject, Valve Lash.

5. Worn Push Rods

If there is too much wear, install new push rods. Make adjustment of valve lash according to subject, Valve Lash.

6. Broken Or Worn Valve Lifters

Install new valve lifters. Check camshaft for wear. Check for free movement of valves or bent valve stem. Clean engine thoroughly. Make adjustment of valve lash according to subject, Valve Lash.

7. Worn Lobes On Camshaft

Check valve lash. Check for free movement of valves or bent valve stems. Install a new camshaft. Install new valve lifters. Make adjustment of valve lash according to subject, Valve Lash.

8. Loose Or Broken Rocker Shaft Retaining Bolt

Repair or replace as necessary.

Problem 18: Valve Rotocoil Or Spring Lock Is Free

Probable Cause:

1. Cracked Inlet Valve Rotocoil

Check for causes for engine overspeed.

2. Broken Locks

Broken locks can cause the valve to slide into the cylinder. This will cause much damage.

3. Broken Valve Spring(s)

Install new valve spring(s)

4. Broken Valve

Replace valve and other damaged parts.

Problem 19: Oil At The Exhaust

Probable Cause:

1. Failure Of Seal Rings In Turbocharger

Check inlet manifold for oil and make repairs to the turbocharger if necessary.

2. Too Much Oil In The Valve Compartment

Be sure that the dowel is installed in the left bolt hole of the rocker shaft.

3. Worn Valve Guides

Reconditioning of the cylinder head is needed.

4. Worn Piston Rings

Inspect and install new parts as needed.

5. Cracked Or Broken Cast Iron Band In Piston

Check for high crankcase pressure [over 102 mm (3 in) of water].

Problem 20: Little Or No Valve Lash

Probable Cause:

1. Worn Valve Seat Or Face Of Valve

Reconditioning of cylinder head is needed. Make adjustment of valve lash according to the subject, Valve Lash.

Problem 21: Engine Has Early Wear

Probable Cause:

1. Dirt In Lubrication Oil

Remove dirty lubrication oil. Install new filters. Put clean oil in the engine. Check oil filter bypass valve for a weak or broken spring.

2. Air Inlet Leaks

Inspect all gaskets and connections. Make repairs if leaks are found.

3. High Horsepower

Incorrect governor torque rise mechanism schedule. Replace governor.

4. Fuel Leakage Into Lubrication Oil

This will cause high fuel consumption and low engine oil pressure. This condition may also increase the oil level in the crankcase. Make repairs if leaks are found. Install new parts where needed.

Problem 22: Coolant In Lubrication Oil

Probable Cause:

1. Failure Of Any Of The Oil Cooler Cores

Install a new core for the defective oil cooler. Drain crankcase and refill with clean lubricant. Install new oil filters.

2. Failure Of Cylinder Head-Gasket Or Water Seals

Check cylinder liner projection. Install a new cylinder head gasket and new water seals in the spacer plate. Tighten the bolts that hold the cylinder head according to the Specifications.

3. Crack Or Defect In Cylinder Head

Install a new cylinder head.

4. Crack Or Defect In Cylinder Block

Install a new cylinder block.

5. Failure Of Liner Seals

Replace seals.

6. Cracked Or Broken Cylinder Liner

Replace cylinder liner.

Problem 23: Too Much Black Or Gray Smoke

Probable Cause:

1. Not Enough Air For Combustion

Check air cleaner for restrictions. Check for failed turbocharger. Check for inlet air leakage. Check for exhaust leakage between cylinder head and turbocharger.

2. Defective Fuel Injectors

Install new fuel injectors.

3. Wrong Fuel Injection Timing

Make adjustments to timing. See subject, Fuel Timing.

Problem 24: Too Much White Or Blue Smoke

Probable Cause:

1. Too Much Lubrication Oil In Engine

Remove extra oil. Find where extra oil comes from. Put correct amount of oil in engine.

2. Engine Misfires Or Runs Rough

Make Reference to Problem 6.

3. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

4. Worn Valve Guides

Reconditioning of cylinder head is needed.

5. Worn Piston Rings

Install new piston rings.

6. Failure Of Turbocharger Oil Seal

Check inlet manifold for oil and repair turbocharger if necessary.

7. Cold Inlet Air

Use ether starting aid or block heater.

Problem 25: Engine Has Low Oil Pressure

Probable Cause:

1. Oil Level Low

Add oil if needed.

2. Dirty Oil Filters Or Oil Cooler(s)

Check the operation of bypass valve for the filter. Install new oil filters if needed. Clean or install new oil cooler core(s). Remove dirty oil from engine. Put clean oil in engine.

3. Diesel Fuel In Lubrication Oil

Find the place where diesel fuel gets into the lubrication oil. Make repairs as needed. Remove the lubrication oil that has diesel fuel in it. Install new oil filters. Put clean oil in the engine.

4. Too Much Clearance Between Rocker Arm Shaft And Rocker Arms

Check lubrication in valve compartments. Install new parts as necessary.

5. Oil Pump Suction Pipe Has A Defect

Replacement of pipe is needed.

6. Oil Pressure Relief Valve Does Not Close

Clean valve and housing. Install new parts as necessary.

7. Oil Pump Has A Defect

Repair or replace oil pump.

8. Too Much Clearance Between Crankshaft And Crankshaft Bearings

Inspect the bearings and make replacement as necessary.

9. Too Much Clearance Between Camshaft And Camshaft Bearings

Install new camshaft and camshaft bearings if necessary.

10. Defect In Oil Pressure Gauge

Install new gauge.

Problem 26: Engine Uses Too Much Lubrication Oil

Probable Cause:

1. Too Much Lubrication Oil In Engine

Remove extra oil. Find where extra oil comes from. Put correct amount of oil in engine.

2. Oil Leaks

Find all oil leaks. Make repairs as needed. Check for dirty crankcase breather(s).

3. Oil Temperature Is Too High

Check operation of oil cooler(s). Install new parts if necessary. Clean the core of the oil cooler(s).

4. Too Much Oil In The Valve Compartment

Be sure that the dowel is installed in the left bolt hole of the rocker shaft. This dowel is located between the rocker shaft and valve cover base.

5. Worn Valve Guides

Reconditioning of the cylinder head is needed.

6. Worn Piston Rings

Inspect and install new parts as needed.

7. Failure Of Seal Rings In Turbocharger

Check inlet manifold for oil and make repairs to the turbocharger if necessary.

Problem 27: Engine Coolant Is Too Hot

Probable Cause:

1. Restriction To Flow Of Coolant Through Core Tubes Of Radiator Or Heat Exchanger

Clean and flush radiator or heat exchanger.

2. Not Enough Coolant In System

Add coolant to cooling system. Check for leaks.

3. Pressure Relief Valve Has A Defect

Check operation of pressure relief valve. Install a new valve if necessary.

4. Combustion Gases In Coolant

Find where gases get into the cooling system. Make repairs as needed.

5. Water Temperature Regulators (Thermostats) Or Temperature Gauge Has A Defect

Check water temperature regulators for correct operation. Check temperature gauge operation. Install new parts as necessary.

6. Radiator Core Fins Clogged

Clean radiator core.

7. Jacket Water Pump Has A Defect

Make repairs to the jacket water pump as necessary.

8. Aftercooler Pump Has A Defect

Make repairs to the aftercooler pump as necessary.

9. Too Much Load On The System

Make a reduction to the load.

10. Wrong Fuel Injection Timing

Make adjustment to timing. See subject, Fuel Timing.

Problem 28: Alternator Gives No Charge

Probable Cause:

1. Loose Drive Belts For Alternator

Make an adjustment to put the correct tension on the drive belts.

2. Charging Or Ground Return Circuit Or Battery Connections Have A Defect

Inspect all cables and connections. Clean and tighten all connections. Make replacements of parts with defect.

3. Rotor (Field Coil) Has A Defect

Install a new rotor.

Problem 29: Alternator Charge Rate Is Low Or Not Regular

Probable Cause:

1. Loose Drive Belts For Alternator

Make an adjustment to put the correct tension on the drive belts.

2. Charging Or Ground Return Circuit Or Battery Connection Have A Defect

Inspect all cables and connections. Clean and tighten all connections. Make replacement of parts with defects.

3. Alternator Regulator Has A Defect

If a replacement of the regulator is needed, the alternator must be disassembled.

4. Rectifier Diodes Have A Defect

Make a replacement of rectifier diode that has a defect.

5. Rotor (Field Coil) Has A Defect

Install a new rotor.

Problem 30: Alternator Charge Too High

Probable Cause:

1. Alternator Or Alternator Regulator Has Loose Connections

Tighten all connections to alternator or alternator regulator.

2. Alternator Regulator Has A Defect

If a replacement of the regulator is needed, the alternator must be disassembled.

Problem 31: Alternator Has Noise

Probable Cause:

1. Drive Belts For Alternator Are Worn Or Have A Defect

Install new drive belts for the alternator.

2. Loose Alternator Drive Pulley

Check groove in pulley for key that holds pulley in place. If groove is worn, install a new pulley. Tighten pulley nut according to Specifications.

3. Drive Belts And Drive Pulley For Alternator Are Not In Alignment

Make an adjustment to put drive belt and drive pulley in correct alignment.

4. Worn Alternator Bearings

Install new bearings in the alternator.

Problem 32: Exhaust Temperature Is Too High

Probable Cause:

1. Air Inlet System Has A Leak

Check pressure in the air inlet manifold. Look for restrictions at the air cleaner. Correct and leaks.

2. Exhaust System Has A Leak

Find cause of exhaust leak. Make repairs as necessary.

3. Air Inlet Or Exhaust System Has A Restriction

Replace air cleaner element as needed. Make repairs to exhaust system as needed.

4. Wrong Fuel Injection Timing

Make an adjustment to the timing. See subject, Fuel Timing.

Problem 33: Air Starter Motor Does Not Turn

Probable Cause:

1. Battery Has Low Or No Output

Check condition of battery. Check alternator charging output. Charge battery or make replacement as necessary.

2. Air Tank Has Little Or No Air Pressure

Charge air system from an outside source.

3. Wiring Or Key Start Switch Has Defect

Make repair or replacement of air start control valve.

4. Air Start Control Valve Has A Defect

Make repair or replacement of air start control valve.

5. Air Relay Valve Has A Defect

Make repair or replacement of air relay valve.

6. Air Starter Motor Has A Defect

Make repair or replacement of air starter motor.

Problem 34: Air Starter Motor Turns Slowly Or Has A Loss Of Power

Probable Cause:

1. Low Supply Air Pressure

Check system for air leaks. Check air compressor and its governor for correct operation. This governor is set to add air when system air reaches a minimum of 660 kPa (95 psi) and shutoff at a minimum of 800 kPa (115 psi).

2. Pressure Regulator Adjustment Not Correct

Make an adjustment to the air pressure regulator.

3. Lubricator Not Working Correctly

Check the lubricator, inlet air hose, fitting and fuel supply hose to make sure they are vacuum tight and free of leaks. Make sure fuel is available at the lubricator. Clean and tighten all fittings.

4. Worn Motor Parts

Disassemble the motor and make an inspection of the parts. A guide for determining worn parts that can not be use again is as follows:

a. Install a set of new vanes if any vane is cracked, damaged or worn to the extent that its width is 32 mm (1.25 in) at either end.

b. Replace rotor bearings if any roughness or looseness is apparent in the bearings.

c. Replace rotor if the body has deep scoring that can not be removed with the use of emery cloth.

d. Replace cylinder if there are any cracks or deep scoring.

e. Clean up end plate scoring with emery cloth placed on a flat surface.

5. Air Leakage

Check the motor for worn seals. Plug the exhaust. Apply 205 kPa (30 psi) air to the inlet and put the unit in nonflammable fluid for 30 seconds. If bubbles appear, make replacement of the motor seals.

Problem 35: Air Starter Motor Pinion Does Not Engage With The Flywheel

Probable Cause:

1. Broken Clutch Jaws Or Other Parts

Make a replacement of the parts.

Problem 36: Air Starter Motor Runs, Pinion Engages But Does Not Turn The Flywheel

Probable Cause:

1. Broken Shafts, Gears (Flywheel Teeth) Or Clutch Jaws

Make replacement of the parts.

Problem 37: Air Starter Motor Pinion Does Not Engage Correctly Engage With The Flywheel

Probable Cause:

1. Dry Pinion Shaft

Remove the drive pinion and put clean grease on the drive shaft splines and drive pinion.

Problem 38: Electric Starter Motor Does Not Turn

Probable Cause:

1. Battery Has Low Output

Check condition of battery. Charge battery or make replacement as necessary.

2. Wiring Or Switch Has Defect

Make repairs or replacement as necessary.

3. Starter Motor Solenoid Has Defect

Install a new solenoid.

4. Starter Motor Has Defect

Make repair or replacement of starter motor.

Fuel System

Either too much fuel or not enough fuel for combustion can be the cause of a problem in the fuel system.

Many times work is done on the fuel system when the problem is really 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 defective fuel injector, but it can also be caused by one or more of the reasons that follow:

a. Not enough air for good combustion.

b. An overload at high altitude.

c. Oil leakage into combustion chamber.

d. Not enough compression.

Fuel System Inspection

A problem with the components that send fuel to the engine can cause low fuel pressure. This can decrease engine performance.

1. 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 new main fuel filters. Clean the primary fuel filter.

4. Inspect the fuel pressure relief valve in the fuel transfer pump to see that there is no restriction to good operation.

Checking Engine Cylinders Separately

Refer to Measurement Of Exhaust Temperature in this manual for procedure to check exhaust manifold port temperatures.

Fuel Injector Testing

Testing of the injectors must be done off the engine. Use 1U6661 Injector Pop Tester Group (or 6V4022 Injector Pop Tester Group), and a 1U6664 Injector Holding Block, to test the injectors. For the 6V4022 Injector Pop Tester Group, refer to Special Instruction, SEHS7788. For the 1U6661 Injector Pop Tester Group, refer to Special Instruction, SEHS8867.

Fuel Pressure

The 1U5470 Engine Pressure Group can be used to check engine fuel pressures.

1U5470 Engine Pressure Group

This tool group has a gauge to read pressure in the fuel manifolds. Special Instruction, SEHS8524 is with the tool group and gives information for its use.

The fuel pressure regulating valve keeps the pressure in fuel manifolds (1) between 415 and 450 kPa (60 to 65 psi). To check the fuel manifold pressure, disconnect one of the fuel lines (2) and install a tee between the line and manifold. Connect the 1U5470 Engine Pressure Group to the tee and operate the engine.

Fuel Manifold And Lines (Typical Example)
(1) Fuel manifold. (2) Fuel supply line to cylinder head.

Fuel Priming Pump And Fuel Filter
(3) Fuel priming pump. (4) Fuel filter pop-up indicator (filter differential pressure). (5) Fuel filter housing.

The outlet pressure of the fuel transfer pump can be checked at the location of fuel filter pop-up indicator (4) on the fuel priming pump (3).

Engine Rotation

SAE standard engine crankshaft rotation is counterclockwise as seen from the flywheel end of the engine.

Finding Top Center Position For No. 1 Piston

Timing Bolt Location (Typical Illustration)
(1) Cover. (2) Timing bolt. (3) Plug in timing bolt hole.

1. Remove cover (1) and the timing hole plug (3) from the right front side of the flywheel housing.

2. Put timing bolt (2) [long bolt that holds cover (1) on the flywheel housing] through the timing hole in the flywheel housing. Use the 9S9082 Engine Turning Tool (4) and 1/2 inch drive ratchet wrench to turn the engine flywheel in the direction of normal engine rotation until the timing bolt engages with the threaded hole in the flywheel.

NOTE: If the flywheel is turned beyond the point that the timing bolt engages in the threaded hole, the flywheel must be turned opposite normal engine rotation approximately 30 degrees. Then turn the flywheel in the direction of normal engine rotation until the timing bolt engages with the threaded hole. The reason for this procedure is to make sure the play is removed from the gears when the No. 1 piston is put on top center.

3. Remove the valve cover for the No. 1 cylinder head.

Timing Bolt Installation (Typical Illustration)
(2) Timing bolt. (4) 9S9082 Engine Turning Tool.

4. The intake and exhaust valves for the No. 1 cylinder are fully closed if No. 1 piston is on the compression stroke and the rocker arms can be moved by hand. If the rocker arms can not be moved and the valves are slightly open, the No. 1 piston is on the exhaust stroke. Make reference to charts for Crankshaft Positions For Fuel Timing And Valve Lash Setting to find the correct cylinder(s) to be checked/adjusted for the stroke position of the crankshaft when the timing bolt has been installed in the flywheel.

NOTE: When the actual stroke position is identified, and the other stroke position is needed, it is necessary to remove the timing bolt from the flywheel and turn the flywheel 360 degrees in the direction of normal engine rotation.

Cylinder And Valve Location

Camshaft Timing

Timing Check

1. Remove rear camshaft cover (3) from both sides of the engine.

Location Of Timing Pins (Typical Example)
(1) Timing hole. (2) Timing pin. (3) Cover.

2. Make reference to Finding Top Center Position For No. 1 Piston.

NOTE: Since both rear camshaft covers have to be removed to check the timing, it is not necessary to remove No. 1 valve cover to find the compression stroke when timing bolt is installed in flywheel.

3. With timing bolt installed in flywheel, look at rear of camshaft to see if timing groove (slot) is visible on the camshaft. If it is visible, No. 1 piston is on the compression stroke. If it is not visible, feel the backside of the camshaft for the groove. If the groove is at the back of the camshaft, the flywheel will have to be turned 360 degrees to put No. 1 piston on the compression stroke.

Installation Of Timing Pins (Typical Example)
(2) Timing pin. (4) Camshaft (L.H.).

4. With timing bolt installed in flywheel with No. 1 piston now on compression stroke, remove timing pins (2) from their storage positions.

5. Install timing pins (2) through holes (1) in the engine block and into the groove (slot) in camshaft (4) on each side of the engine. For the engine to be timed correctly, the timing pins must fit into the groove of each camshaft.

6. If timing pins (2) do not engage in the grooves of both camshafts, the engine is not in time, and one or both camshafts must be adjusted.

7. Both camshafts are adjusted the same way. See subject, Timing Adjustment for the procedure to put the camshafts in time with the crankshaft.

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NOTICE

If a camshaft is out of time more than 18 degrees (approximately 1/2 the diameter of timing pin out of groove), the valves can make contact with the pistons. This will cause damage that will make engine repair necessary.

Timing Adjustment

NOTE: Before any timing adjustments are made, the timing must be checked first to see if adjustment is necessary. See subject, Timing Check for this procedure.

After Timing Check procedure is complete, timing bolt will be engaged in flywheel with No. 1 piston at top center (TC) position.

Loosen Rocker Shafts (Typical Example)
(1) Bolt. (2) Rocker shaft.

1. Remove all valve covers on the same side of the engine that camshaft needs adjustment. Now loosen bolts (1) [that hold all rocker shafts (2) to valve cover bases] until all rocker arms are free from the injectors and the valves.

NOTE: The above procedure must be done before camshaft drive gear (3) is pulled off the camshaft taper.

2. Remove the cover(s) from the flywheel housing.

Camshaft Drive Gears (Typical Example)
(3) Drive gear. (4) Plate. (5) Bolt.

3. Install the 6V3010 Puller Group, two 8S9089 Bolts and two 5P1076 Washers. Loosen drive gears (3) from the taper on the camshafts. Remove the tooling and the gears.

4. Remove timing pin(s) (6) from the storage position (under the rear camshaft covers) on each side of the engine.

Camshaft Timing Pin Installed (Typical Example)
(6) Timing pin.

5. Turn the camshafts until timing pins (6) can be installed through the engine block and into the grooves (slots) in the camshafts.

6. Install camshaft drive gears (3) as follows:

a. Put camshaft drive gears (3) in position on the camshafts.

b. Use hand pressure to turn and hold camshaft drive gears in the opposite direction of rotation. This removes all gear clearance (backlash) between camshaft drive gears (3) and the idler gears.

c. Install plate (4) to hold camshaft drive gears (3) to each camshaft.

d. Tighten the bolts in steps to a torque of 360 ± 40 N·m (270 ± 30 lb ft).

e. Hit the face of the plate, then tighten the bolts to a torque of 360 ± 40 N·m (270 ± 30 lb ft).

f. Again hit the face of the plate and again tighten the bolts to a torque of 360 ± 40 N·m (270 ± 30 lb ft).

NOTE: If necessary, do step 6f until the bolts hold torque (cannot be moved) to make sure the drive gears are in full contact with the taper on the camshafts.

7. Install the gaskets and covers on the flywheel housing.

8. Remove timing pins (6) from the camshafts. Install timing pins (6) in their storage positions. Install cover(s) (7) over the camshafts and timing pins.

Storage Position For Timing Pins (Typical Example)
(6) Timing pin. (7) Cover.

9. Remove the timing bolt from the flywheel housing. Install the 5M6213 Plug in the flywheel housing timing hole. Remove the engine turning pinion and install the cover and gasket.

10. Make sure the rocker arms are engaged correctly with the push rods, and tighten the bolts to hold all of the rocker shafts in position.

11. Make adjustments to the valves and fuel timing. See Valve Lash Setting and Fuel Timing for the correct procedures.

Start Up Procedure

Use this procedure when an engine is started for the first time after work is done on the fuel system or governor.

1. Disconnect the air inlet system from the turbochargers.

2. Have a person in position near each turbocharger air inlet with a piece of steel plate large enough to completely cover the turbocharger air inlet.

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Be careful when plate is put against air inlet opening. Due to excessive suction, the plate can be pulled quickly against air inlet openings. To avoid crushed fingers, do not put fingers between plate and air inlet opening.

3. Start the engine. If the engine starts to run too fast or runs out of control, immediately put the steel plates against the turbocharger air inlets. This will stop the air supply to the engine, and the engine will stop.

Crankshaft Positions For Fuel Timing And Valve Lash Setting

Cylinder And Valve Location

Fuel Timing

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NOTICE

The camshafts must be correctly timed with the crankshaft before an adjustment of fuel timing is made. The timing pins must be removed from the camshafts before the crankshaft is turned or damage to the cylinder block will be the result.

NOTE: See chart Crankshaft Positions For Fuel Timing And Valve Lash Setting and put the engine in time. With the two crankshaft positions given in the chart, all of the injectors can be checked or adjusted. This will make sure the pushrod lifters are off the lobes and on the base circles of the camshafts.

NOTE: See the Fuel Setting And Related Information Fiche for the correct fuel timing dimension to use.

NOTE: Two dial indicators, each with their own procedure, are available to set fuel timing. Checking or setting fuel timing with the 1U8869 Digital Dial Indicator is the preferred method.

Procedure A (1U8869 Digital Dial Indicator) - Preferred Method

1U8869 Digital Dial Indicator

1. The digital dial indicator needs to be programmed to read actual timing dimensions. Since the 6V3117 Gauge in the timing and fuel setting tool group is 87.00 mm, the digital dial indicator is to be programmed for 87.00 mm. The following steps show how to program the indicator to read 87.00 mm.

a. Turn the indicator ON by pushing the "on/off" button.

b. Push the "in/mm" button so the display shows mm.

c. A negative (-) sign should be in the display window under REV. If that space is blank, push the +/- button so the display shows (-). When this is done, plunger movement into the indicator will show on the display as negative movement, and plunger movement out of the indicator as positive movement.

d. Push and hold the preset button down until there is a flashing (P) in the upper right corner of the display, and then release the button.

e. Push and hold the preset button down until the flashing (P) disappears, and a flashing indicator bar is seen in the lower left corner of the display, and then release. Momentarily pushing the preset button will cause a minus sign to appear or disappear above the flashing indicator. Use the preset button so that this position is blank.

f. Push and hold the preset button down until flashing indicator begins flashing under the first number position (fourth position to the left of the decimal), then release. Momentarily pushing the preset will cause the display number in that position to change. Use the preset until this position reads zero (0).

g. Use the preset button to move the flashing indicator and change the display numbers until the display shows 0087.00 mm. Push and hold the preset button until the flashing (P) is shown in the upper right corner of the display, and then release. Momentarily push the preset button so the flashing (P) and the zeros to the left of 87.00 mm disappear.

h. The indicator can now be turned off if desired. The indicator will retain the preset number in memory (only one preset number is retained). To recall the preset number, repeat Steps 1a through 1d.

2. Install a 5P4160 Contact Point, 19 mm (.75 in) long, in the indicator stem.

3. Install the indicator in the 6V7881 Timing Fixture. Leave the collet loose.

Adjustment Of Fuel Timing Tools
(1) 1U8869 Digital Dial Indicator. (2) 6V7881 Timing Fixture. (3) 6V3117 Gauge.

4. Place the fixture and indicator on the 6V3117 Gauge with the extension rod of the bracket on the step of the gauge. Position the indicator in the bracket so the indicator plunger has adequate travel and tighten the collet.

5. Repeat Steps 1a through 1d.

6. Momentarily push the "preset" button on the digital dial indicator to stop the P in the upper right hand corner from flashing. The display should show 87.00 mm. Place the 1U8869 Digital Dial Indicator and the 6V7881 Timing Fixture in position on the injector to be checked. Make sure the magnetic base of the timing fixture is on the top surface of follower (4) and the extension rod is on the top surface of injector shoulder (5).

NOTE: To insure an accurate fuel timing dimension, make sure the top surfaces of the follower (4) and shoulder (5) are clean and dry.

Fuel Timing Tools In Position
(1) 1U8869 Digital Dial Indicator. (2) 6V7881 Timing Fixture. (4) Injector follower. (5) Shoulder on injector body.

7. The digital dial indicator should now read the actual fuel timing dimension of the injector being checked.

8. If the dial indicator reads the correct fuel timing dimension, as determined from the Fuel Setting And Related Information Fiche for the engine being checked, then no adjustment is necessary. Proceed to Step 12.

9. If the dial indicator does not read the correct and/or desired fuel timing dimension, as determined from the Fuel Setting And Related Information Fiche for the engine being checked, do Steps 10 through 13.

10. With the 1U8869 Digital Dial Indicator and the 6V7881 Timing Fixture in position on the injector to be adjusted, loosen the push rod adjustment screw locknut for the injector to be adjusted.

11. Turn the adjustment screw until the desired fuel timing dimension is read on the digital dial indicator.

NOTE: Turning the adjustment screw clockwise (CW) will lower the fuel timing dimension (advance timing). Turning the adjustment screw counterclockwise (CCW) will increase the fuel timing dimension.

Tighten the adjustment screw locknut to a torque of 70 ± 15 N·m (50 ± 11 lb ft) and check adjustment again. If necessary, repeat procedure until the adjustment is correct.

12. Remove the timing bolt from the flywheel when the fuel timing check is completed.

13. Rotate engine, repin flywheel, and repeat procedure for other half.

Procedure B (6V3075 Dial Indicator) - Alternate Method

NOTE: See the Fuel Setting And Related Information Fiche for the correct fuel timing dimension to use.

Adjustment Of Fuel Timing Tools
(1) 6V3075 Dial Indicator. (2) 6V7881 Timing Fixture. (3) 6V3117 Gauge.

1. Install the 8S3675 Contact Point on the dial indicator stem.

2. Install 6V3075 Dial Indicator (1) in the collet of 6V7881 Timing Fixture (2).

3. Put the dial indicator and timing fixture on 6V3117 Gauge (3). The magnetic base of the timing fixture should be placed on the top surface of the gauge and the extension rod on the bottom step.

4. Move the dial indicator in the collet until all three needles indicate zero. Do not tighten collet. At this point the dial indicator has been zeroed to a standard fuel timing dimension of 87.00 mm using the gauge (gauge height is 87.00 mm).

5. Subract 87.00 mm (gauge dimension) from the desired fuel timing dimension (obtained from the Fuel Setting And Related Information Fiche).

Example 1: Desired fuel timing dimension is 87.50 mm.

Subtract 87.00 mm from the desired fuel timing dimension (87.50 mm).

87.50 mm - 87.00 mm = + .50 mm

In this case move the dial indicator downward until the indicator reads a positive .50 mm. Then lock the collet.

Example 2: Desired fuel timing dimension is 86.20 mm.

Subtract 87.00 mm from the desired fuel timing dimension (86.20 mm).

86.20 mm - 87.00 mm = - .80 mm

In this case move the dial indicator upward until the indicator reads a negative .80 mm. Then lock the collet.

NOTE: Positive indicator setting. Moving the indicator downward moves the large needle clockwise (CW) or in the positive direction (increase in fuel timing dimension from 87.00 mm).

NOTE: Negative indicator setting. Moving the indicator upward moves the large needle counterclockwise (CCW) or in the negative direction (decrease in fuel timing dimension from 87.00 mm).

6. Make sure the top surfaces of injector follower (4) and shoulder (5) are clean and dry.

Fuel Timing Tools In Position
(1) 6N3075 Dial Indicator. (2) 6V7881 Timing Fixture. (4) Injector follower. (5) Shoulder on injector body.

7. Put 6V3075 Dial Indicator (1) and 6V7881 Timing Fixture (2) in position on the injector to be checked. Make sure the magnetic base of the timing fixture is on the top surface of follower (4) and the extension rod is on the top surface of injector shoulder (5).

8. The dial indicator pointers must indicate 0.00 ± 0.20 mm.

9. If the dial indicator pointers indicate zero, or are within the tolerance given in Step 8, no adjustment is necessary. Proceed to Step 13.

10. If the dial indicator pointers do not indicate 0.00 ± 0.20 mm, do Steps 11 through 13.

11. Loosen the push rod adjustment screw locknut for the injector to be adjusted.

12. Turn the adjustment screw until zero is read on the dial indicator.

NOTE: If the dial indicator reading is greater than 0.00 ± 0.20 mm, then the timing is too far advanced. Turn the adjustment screw counterclockwise (CCW).

NOTE: If the dial indicator reading is less than 0.00 ± 0.20 mm, then the timing is too far retarded. Turn the adjustment screw clockwise (CW).

Tighten the adjustment screw locknut to a torque of 70 ± 15 N·m (50 ± 11 lb ft) and check adjustment again. If necessary, repeat procedure until the adjustment is correct.

Adjustment Of Fuel Timing (Typical Example)

13. Rotate engine, repin flywheel and repeat procedure for other half.

Injector Synchronization

Injector synchronization is the setting of all injector racks to a reference position so each injector gives the same amount of fuel to each cylinder. This is done by setting each injector rack to the same position while the control linkage is in a fixed position (called the synchronizing position). The procedure for adjustment of injector synchronization is as follows:

Location Of Fuel Setting Cover And Synchronizing Pin (Typical Example)
(1) Plug. (2) Synchronizing pin. (3) Cover.

1. The top bolt that holds cover (3) in position is synchronizing pin (2). Remove synchronizing pin (2) and plug (1) from the front drive housing. DO NOT destroy seal or remove cover (3).

2. Remove the washer from synchronizing pin (2) and install it into the threaded hole where plug (1) was removed. Tighten synchronizing pin (2).

Synchronizing Position (Governor Fastener Cover Removed Only For Illustration) (Typical Example)
(2) Synchronizing pin. (4) Fuel stop lever.

3. Turn the governor or actuator terminal shaft to the fuel "ON" position until the flat face of fuel stop lever (4) contacts synchronizing pin (2). This is the synchronizing position or zero reference point. Hold the control linkage in this position when the injectors are adjusted.

4. Remove the valve covers.

Location For Gauge And Control Rod Adjustment (Rocker Shaft Removed for Illustration) (Typical Example)
(5) 8T2684 Rack Synchronizing Gauge [12.7 mm (.50 in)]. (6) Control rod.

5. With the fuel stop lever against the synchronizing pin, put 8T2684 Rack Synchronizing Gauge (5) on the round part of the injector rack between the injector body and the end of the rack. Use a screwdriver and make an adjustment of control rod (6). Turn the screw on control rod (6) one "click" at a time until rack synchronizing gauge (5) just fits between the injector body and the shoulder at the end of the rack. Remove the screwdriver from control rod (6) so no pressure is on the linkage while the setting is checked with rack synchronizing gauge (5). Any pressure on the linkage with the screwdriver will not give a correct indication when the setting is checked with the rack synchronizing gauge. To make sure the linkage is free and giving the correct setting, move (flip) the linkage and check the setting again. Put the box end of a 9/16 or 5/8 inch combination wrench over the nut and bolt that holds control rod (6) and the bellcrank together. Pull up on the control rod two or three times; then check the setting again.

Gauge In Position On Injector Rack (Rocker Shaft Removed for Illustration) (Typical Example)
(5) 8T2684 Rack Synchronizing Gauge [12.7 mm (.50 in)]. (7) Fuel injector rack.

6. Use rack synchronizing gauge (5) and, if necessary, make the adjustment to the other injectors. When all adjustments have been made, release the actuator terminal shaft.

Adjustment Of Fuel Control Rod (Typical Example)
(5) 8T2684 Rack Synchronizing Gauge.

7. Install the valve covers.

8. Make a check of the fuel setting and make adjustments if necessary. See the subject Fuel Setting for this procedure.

Fuel Setting

Refer to Special Instruction, SEHS9278 for instructions on the use of the 4C8753 Extended Collet.

Fuel Setting Check

Fuel setting is the adjustment of the fuel setting screw to a specified position. The fuel setting screw limits the power output of the engine by setting the maximum travel of all the injector racks.

Synchronization And Fuel Setting Tools
(1) 8T2684 Rack Synchronizing Gauge. (2) 6V3075 Dial Indicator (metric). (3) 4C8753 Extended Collet. (4) 5P7263 Contact Point, 76.2 mm (3.00 in) long.

Before the fuel setting is checked, the injectors must be correctly synchronized. See the subject, Injector Synchronization. After the injectors are synchronized correctly, leave the synchronizing pin in place for the procedure that follows.

1. Put 6V3075 Dial Indicator (2) with 5P7263 Contact Point (4) in 4C8753 Extended Collet (3). Remove the plug from the right side of fuel setting cover (8).

Install Dial Indicator (Typical Example)
(2) 6V3075 Dial Indicator with 5P7263 Contact Point attached. (3) 4C8753 Extended Collet.

2. Move the governor or actuator terminal shaft in the fuel "ON" direction until the flat face of fuel stop lever (6) contacts synchronizing pin (5). Hold the linkage in this position.

Dial Indicator In Position (Cover Removed Only for Photo Illustration) (Typical Example)
(2) 6V3075 Dial Indicator. (4) 5P7263 Contact Point, 76.2 mm (3.00 in) long. (5) Synchronizing pin. (6) Fuel stop lever.

3. Install the dial indicator and collet (3) in the threaded hole as shown. When the contact point seats against fuel stop lever (6), slide the dial indicator in or out until the indicator reads zero. Now tighten collet (3) just enough to hold indicator at this position.

Checking Fuel Setting (Typical Example)
(2) 6V3075 Dial Indicator (metric). (5) Synchronizing pin. (8) Fuel setting cover.

4. Turn synchronizing pin (5) back out a minimum of 25 mm (1 in) (or remove it completely), and then slowly move the governor or actuator terminal shaft in the fuel "ON" direction until the flat face of the fuel stop lever is against the end of the fuel setting screw. With the linkage held in this position, the dial indicator reading will be the present fuel setting.

NOTE: See Fuel Setting And Related Information Fiche for the correct fuel setting.

5. If fuel setting is correct, remove the dial indicator and synchronizing pin (5). Install the two plugs, and install pin (5) back into cover (8).

6. If fuel setting needs adjustment, go on to Fuel Setting Adjustment.

Fuel Setting Adjustment

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NOTICE

A mechanic with governor and fuel setting training is the ONLY one to make adjustments to the engine fuel setting.

1. Cut the seal wire and remove fuel setting cover (8) and the gasket. Loosen locknut (7) and (with fuel stop lever still held against end of the fuel setting screw) turn the fuel setting screw in or out until the correct reading is on the dial indicator.

Adjustment Of The Fuel Setting Screw (Typical Example)

2. Now tighten locknut (7). Be sure that the fuel setting screw does not turn when the locknut (7) is tightened. Release the fuel linkage and again move linkage all the way in the fuel "ON" direction. Check the dial indicator reading again to be sure that fuel setting is still correct.

3. Remove the dial indicator and synchronizing pin (5), then install the two plugs.

Install Cover (Typical Example)
(7) Locknut. (8) Fuel setting cover.

4. Put fuel setting cover (8) and gasket in position over the fuel setting screw and install bolt and synchronizing pin (5) in cover. Install a new seal wire.

Engine Speed Measurement

6V3121 Multitach Group

The 6V3121 Multitach 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, SEHS7807 is with the 6V3121 Multitach Group and gives instructions for the test procedure.

Air Inlet And Exhaust System

Restriction Of Air Inlet And Exhaust

There will be a reduction of horsepower and efficiency of the engine if there is a restriction in the air inlet or exhaust system.

Air flow through the air cleaner must not have a restriction (negative pressure difference measurement between atmospheric air and air that has gone through air cleaner) of more than 762 mm (30 in) of water.

Back pressure from the exhaust (pressure difference measurement between exhaust at outlet elbow and atmospheric air) must not be more than 686 mm (27 in) of water.

Measurement Of Pressure In Inlet Manifold

The efficiency of an engine can be checked by making a comparison of the pressure in the inlet manifold with the specifications given in the Fuel Setting and Related Information Fiche. This test is used when there is a decrease of horsepower from the engine, yet there is no real sign of a problem with the engine.

The correct pressure for the inlet manifold is given in the Fuel Setting and Related Information Fiche. Development of this information is done with these conditions:

a. 737 mm (29 in) of mercury barometric pressure (dry).

b. 29°C (85°F) outside air temperature.

c. 35 API rated fuel.

Any change from these conditions can change the pressure in the inlet manifold. Outside air that has higher temperature and lower barometric pressure than given above will cause a lower horsepower and a lower inlet manifold pressure measurement than given in the Fiche. Outside air that has a lower temperature and a higher barometric pressure will cause higher horsepower and a higher inlet manifold pressure measurement.

A difference in fuel rating will also change horsepower and the pressure in the inlet manifold. If the fuel is rated about 35 API, pressure in the inlet manifold can be less than given in the Fiche. If the fuel is rated below 35 API, the pressure in the inlet manifold can be more than given in the Fiche. BE SURE THAT THE AIR INLET OR EXHAUST DOES NOT HAVE A RESTRICTION WHEN MAKING A CHECK OF PRESSURE IN THE INLET MANIFOLD.

To check the inlet manifold pressure, remove the 1/2-14-NPTF pipe plug (A). Connect the 1U5470 Engine Pressure Group to this opening in the inlet manifold.

Pressure Test Location (Typical Example)
(A) Pipe plug.

This tool group has a gauge to read pressure in the inlet manifold. Special Instruction, SEHS8524 is with the tool group and gives instruction for its use.

1U5470 Engine Pressure Group

Measurement Of Exhaust Temperature

Use the 1U8865 Infrared Thermometer Group to check exhaust temperature. The Operator's Manual, NEHS0510, for the 1U8865 Infrared Thermometer gives complete operating and maintenance instructions for this tool.

Individual cylinder head exhaust temperatures can be checked using the 4C6090 Temperature Selector Group, 6V9130 Temperature Adapter Group and the 6V7070 or 6V7800 Digital Multimeters. Refer to Operating Manual, NEHS0537 for complete operating instructions for the 4C6090 Temperature Selector Group.

Thermocouple Location
(1) Thermocouple.

Crankcase (Crankshaft Compartment) Pressure

Pistons or rings that have damage can be the cause of too much pressure in the crankcase. This condition will cause the engine to run rough. There will also be more than the normal amount of fumes coming from the crankcase breather. This crankcase pressure can also cause the element for the crankcase breather to have a restriction in a very short time. It can also be the cause of oil leakage at gaskets and seals that would not normally have leakage.

Compression

An engine that runs rough can have a leak at the valves, or have valves that need adjustment. Removal of the head and inspection of the valves and valve seats is necessary to find those small defects that do not normally cause a problem. Repair of these problems is normally done when reconditioning the engine.

Cylinder Heads

The cylinder heads have valve seat inserts, valve guides and bridge dowels that can be removed when they are worn or have damage. Replacement of these components can be made with the tools that follow.

Valves

Valve removal and installation is easier with use of the 1P3527 Valve Spring Compressor Assembly.

Valve Seat Inserts

To remove and install valve seat inserts, use the 6V4805 Valve Seat Extractor Group. For Installation, lower the temperature of the insert before it is installed in the head.

Valve Guides

Tools needed to remove and install valve guides are the 5P1729 Bushing and 7M3975 Driver. The counterbore in the driver bushing installs the guide to the correct height. Use a 1P7451 Valve Guide Honing Group to make a finished bore in the valve guide after installation of the guide in the head. Special Instruction, SMHS7526 gives an explanation for this procedure. Grind the valves after the new valve guides are installed.

Checking Valve Guide Bores

Use the 5P3536 Valve Guide Gauge Group to check the bore of the valve guides. Special Instruction, GMG02562 gives complete and detailed instructions for use of the 5P3536 Valve Guide Gauge Group.

5P3536 Valve Guide Gauge Group

Bridge Dowels

Use a 5P0944 Dowel Puller Group with a 5P0942 Extractor to remove the bridge dowels. Install a new bridge dowel with a 6V4009 Dowel Driver. This dowel driver installs the bridge dowel to the correct height.

Bridge Adjustment

When the cylinder head is disassembled, keep the bridges with their respective valves. To make an adjustment to the bridges, use the procedure that follows:

NOTE: The bridges can be adjusted without removal of the rocker arms and shafts. Valves must be fully closed when adjustment is made. To find when valves are fully closed, see subject, Finding Top Center Position For No. 1 Piston and chart Crankshaft Positions For Fuel Timing And Valve Lash Setting.

1. Put engine oil on bridge dowel (4) in the cylinder head and in the bore in bridge (2).

2. Install bridge (2) with adjustment screw (5) toward the exhaust manifold.

Bridge Installation (Typical Example)
(1) Top contact surface. (2) Bridge. (3) Valve stem. (4) Bridge dowel.

3. Loosen the locknut for adjustment screw (5) and loosen the adjustment screw several turns.

4. Put a force of 5 to 45 N (1 to 10 lb) by hand straight down on top contact surface (1) of bridge (2).

5. Turn adjustment screw (5) clockwise until it just makes contact with valve stem (3). Then turn the adjustment screw 20 to 30 degrees more in a clockwise direction to make the bridge straight on the dowel, and to make compensation for the clearance in the threads of the adjustment screw.

Bridge Adjustment (Typical Example)
(5) Adjustment screw.

6. Hold adjustment screw (5) in this position and tighten the locknut to 30 ± 4 N·m (22 ± 3 lb ft).

Tighten Locknut

7. Put engine oil on top contact surface (1) where the rocker arm makes contact with the bridge.

Crankshaft Positions For Fuel Timing And Valve Lash Setting

Cylinder And Valve Location

Valve Lash

Valve lash is measured between the rocker arm and the bridge for the valves. All clearance measurements and adjustments must be made with the engine stopped, and with the valves FULLY CLOSED.

Valve Lash Check

When the valve lash is checked, adjustment is NOT NECESSARY if the measurement is in the range given in the chart for Valve Lash Check: Engine Stopped.

If the measurement is not within this range, or if the service meter indication is at the specified interval, adjustment is necessary. See the subject, Valve Lash Adjustment.

Valve Lash Adjustment

Use one of the two procedures (Procedure A: Feeler Gauge or Procedure B: 4C8241 Valve Lash Setting Gauge) that follows for adjustment of the valves:

Procedure A: Feeler Gauge

1. Put No. 1 piston at top center (TC) position. Make reference to Finding Top Center Position For No. 1 Piston.

2. With No. 1 piston at top center position of the correct stroke, adjustment can be made to the valves as shown in the chart Crankshaft Positions For Fuel Injector Timing Dimension And Valve Lash Setting.

NOTE: Before any actual adjustments are made, tap (hit lightly) each rocker arm (at top of adjustment screw) with a soft hammer to be sure that the lifter roller is seated against the camshaft base circle.

3. Loosen the locknut for the push rod adjustment screw. If there is not enough clearance for feeler gauge between rocker arm and bridge contact surface, turn the adjustment screw counterclockwise to increase the valve lash.

4. Put a feeler gauge of the correct dimension between the rocker arm and bridge contact surface. Turn the adjustment screw clockwise until the valve lash is set to the specifications in the chart Valve Lash Setting: Engine Stopped.

Valve Lash Adjustment (Typical Example)

5. After each adjustment, tighten the nut for the adjustment screw to a torque of 70 ± 15 N·m (50 ± 11 lb ft) and check the adjustment again.

Tighten Adjustment Screw Locknut (Typical Example)

6. Remove the timing bolt and turn the flywheel 360 degrees in the direction of engine rotation. This will put No. 1 piston at top center (TC) position on the opposite stroke. Install the timing bolt in the flywheel.

7. With No. 1 piston at top center position of the opposite stroke, adjustment can be made to the remainder of the valves as shown in the chart Crankshaft Positions For Fuel Injector Timing Dimension And Valve Lash Setting.

8. Repeat Steps 3, 4 and 5 for these valve adjustments.

9. Remove the timing bolt from the flywheel when all valve lash have been adjusted.

Procedure B: 4C8241 Valve Lash Setting Gauge

1. Put No. 1 piston at top center (TC) position. Make reference to Finding Top Center Position For No. 1 Piston.

4C8241 Valve Lash Setting Gauge
(1) 4C8246 Dial Indicator. (2) 4C8242 Gauge Base Assembly.

Install 4C8241 Valve Lash Setting Gauge

3. Install 4C8241 Valve Lash Setting Gauge between the rocker arm and the bridge contact surface. Zero dial indicator (1).

Checking Valve Lash

4. Position a pry bar to apply upward pressure to the front of the rocker assembly as shown. Record valve lash reading.

Adjust Valve Lash

5. Loosen the locknut on the push rod adjustment screw. Turn the adjustment screw until the valve lash is set to specifications. After each adjustment, tighten the nut for the adjustment screw to a torque of 70 ± 15 N·m (50 ± 11 lb ft) and check the adjustment again.

7. With No. 1 piston at top center position of the opposite stroke, adjustment can be made to the remainder of the valves as shown in the chart Crankshaft Positions For Fuel Timing And Valve Lash Setting.

8. Repeat Steps 3, 4 and 5 for these valve adjustments.

9. Remove the timing bolt from the flywheel when the lash for all the valves has been adjusted.

Lubrication System

One of the problems in the list that follows will generally be an indication of a problem in the lubrication system for the engine.

Too Much Oil Consumption

Oil Pressure Is Low

Oil Pressure Is High

Too Much Bearing Wear

Increased Oil Temperature

Too Much Oil Consumption

Oil Leakage on Outside of Engine

Check for leakage at the seals at each end of the crankshaft. Look for leakage at the oil pan gasket and all lubrication system connections. Check to see if oil comes out of the crankcase breather. This can be caused by combustion gas leakage around the pistons. A dirty crankcase breather will cause high pressure in the crankcase, and this will cause gasket and seal leakage.

Oil Leakage Into Combustion Area of Cylinders

Oil leakage into the combustion area of the cylinders can be the cause of blue smoke. There are four possible ways for oil leakage into the combustion area of the cylinders:

1. Oil leakage between worn valve guides and valve stems.

2. Worn or damaged piston rings, or dirty oil return holes in the piston.

3. Compression ring and/or intermediate ring not installed correctly.

4. Oil leakage past the seal rings in the impeller end of the turbocharger shaft.

Too much oil consumption can also be the result if oil with the wrong viscosity is used. Oil with a thin viscosity can be caused by fuel leakage into the crankcase, or by increased engine temperature.

Measuring Engine Oil Pressure

An oil pressure gauge that has a defect can give an indication of low or high oil pressure.

1U5470 Engine Pressure Group

The 1U5470 Engine Pressure Group can be used to measure the pressure in the system. This tool group has a gauge to read pressure in the oil manifold. Special Instruction, SEHS8524 is with the tool group and gives instructions for its use.

Oil Gallery Plug (Typical Example)
(1) Plug.

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Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

Oil pressure to the camshaft and main bearings should be checked on each side of the cylinder block at oil gallery plug (1). With the engine at operating temperature, minimum oil pressure at full load rpm should be approximately 280 kPa (40 psi), and minimum oil pressure at low idle rpm should be approximately 140 kPa (20 psi).

Oil Pressure Is Low

Crankcase Oil Level

Check the level of the oil in the crankcase. Add oil if needed. It is possible for the oil level to be too far below the oil pump supply tube. This will cause the oil pump not to have the ability to supply enough lubrication to the engine components.

Oil Pump Does Not Work Correctly

The inlet screen of the supply tube for the oil pump can have a restriction. This will cause cavitation (low pressure bubbles suddenly made in liquids by mechanical forces) and a loss of oil pressure. Air leakage in the supply side of the oil pump will also cause cavitation and loss of oil pressure. If the bypass valve for the oil pump is held in the open (unseated) position, the lubrication system can not get to maximum pressure. Oil pump gears that have too much wear will cause a reduction in oil pressure.

Oil Filter Bypass Valve

If the bypass valve for the oil filter is held in the open position (unseated) because the oil filter has a restriction, a reduction in oil pressure can result. To correct this problem, remove and clean the bypass valve and bypass valve bore. Install new Caterpillar oil filters.

Too Much Clearance at Engine Bearings or Open Lubrication System (Broken or Disconnected Oil Line or Passage)

Components that are worn and have too much bearing clearance can cause oil pressure to be low. Low oil pressure can also be caused by an oil line or oil passage that is open, broken or disconnected.

Piston Cooling Jets

When engine is operated, cooling jets direct oil toward the bottom of the piston to cool the piston and also provide lubrication for the piston pin. If a jet is broken, plugged or installed wrong, seizure of the piston will be caused in a very short time.

Oil Pressure Is High

Oil pressure will be high if the bypass valve for the oil pump can not move from the closed position.

Too Much Bearing Wear

When some components of the engine show bearing wear in a short time, the cause can be a restriction in an oil passage.

If the gauge for oil pressure shows enough oil pressure, but a component is worn because it can not get enough lubrication, look at the passage for oil supply to the component. A restriction in a supply passage will not let enough lubrication get to a component, and this will cause early wear.

Increased Oil Temperature

Look for a restriction in the oil passages of the oil cooler. If the oil cooler has a restriction, the oil temperature will be higher than normal when the engine is operated. The oil pressure of the engine will not get low just because the oil cooler has a restriction.

Also check the oil cooler bypass valve to see if it is held in the open position (unseated). This condition will let the oil through the valve instead of the oil cooler, and oil temperature will increase.

Gauges For Oil Pressure

An oil pressure gauge or a sender that has a defect can give an indication of low or high oil pressure.

The 1U5470 Engine Pressure Group can be used to make a comparison with instrument panel gauges.

Cooling System

This engine has a pressure type cooling system. A pressure type cooling system gives two advantages. The first advantage is that the cooling system can have safe operation at a temperature that is higher than the normal boiling (steam) point of water. The second advantage is that this type system prevents cavitation (low pressure bubbles suddenly made in liquids by mechanical forces) in the water pump. With this type system, it is more difficult for an air or steam pocket to be made in the cooling system.

Visual Inspection Of The Cooling System

The cause for increased engine temperature is generally because regular inspections of the cooling system were not made. Make a visual inspection of the cooling system before a test is made with test equipment.

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DO NOT loosen the filler cap or pressure cap on a hot engine. Steam or hot coolant can cause severe burns.

1. Check coolant level in the cooling system.

2. Look for leaks in the system.

3. Look for air or combustion gas in the cooling system.

Testing The Cooling System

Remember that temperature and pressure work together. When a diagnosis is made of a cooling system problem, temperature and pressure must both be checked. Cooling system pressure will have an effect on cooling system temperatures. For an example, look at the chart to see the effect of pressure and height above sea level on the boiling (steam) point of water.

Boiling Point Of Water

Test Tools for Cooling System

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Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

8T0470 Thermistor Thermometer Group

The 8T0470 Thermistor Thermometer Group is used in the diagnosis of overheating (engine hotter than normal) or overcooling (engine cooler than normal) problems. This group can be used to check temperatures in several different parts of the cooling system. The testing procedure is in Special Instruction, SEHS8446.

Water Temperature Gauge Test

Test Location
(1) Plug.

Check the accuracy of the water temperature gauge if either of the conditions that follow are found:

1. The gauge reads normal, but the engine is too hot and a loss of coolant is found.

2. The gauge shows that the engine is hot, but no loss of coolant can be found.

Remove plug (1) [1/2 inch Std Pipe Thread] and install the 8T0470 Thermistor Thermometer Group or the 2F7112 Thermometer and 6B5072 Bushing. A temperature gauge of known accuracy can also be used to make this check.

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Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.

Start the engine and run it until the temperature reaches the desired range according to the test thermometer. If necessary cause a restriction of the coolant flow. The reading on the gauge for water temperature should agree with test thermometer within the tolerance range of the gauge.

Water Temperature Regulator Test

1. Remove the regulator from the engine.

2. Heat water in a pan until the temperature is 92°C (197°F). Move the water around in the pan to make it all the same temperature.

3. Hang the regulator in the pan of water. The regulator must be below the surface of the water and it must be away from the sides and bottom of the pan.

4. Keep the water at the correct temperature for ten minutes.

5. After ten minutes, remove the regulator and immediately measure the distance the regulator has opened. The distance must be a minimum of 9.53 mm (.375 in).

6. If the distance is less than 9.53 mm (.375 in), make a replacement of the regulator.

Basic Block

Connecting Rod Bearings

The connecting rod bearings fit tightly in the bore in the rod. If bearing joints or backs are worn (fretted), check bore size. This can be an indication of wear because of a loose fit.

Connecting rod bearings are available with 0.63 mm (.025 in) and 1.27 mm (.050 in) smaller inside diameter than the original size bearings. These bearings are for crankshafts that have been ground (made smaller than original size).

Main Bearings

Main bearings are available with a larger outside diameter than the original size bearings. These bearings are for cylinder blocks that have had the bore for the main bearings "bored" (made larger than the original size). The size available is 0.63 mm (.025 in) larger outside diameter than the original size bearings.

Cylinder Block

The bore in the block for main bearings can be checked with the main bearing caps installed without bearings. Tighten the nuts that hold the caps to the torque shown in the Specifications section. Alignment error in the bores must not be more than 0.08 mm (.003 in). Special Instruction, SMHS7606 gives instructions for the use of 1P4000 Line Boring Tool Group for alignment of the main bearing bores. The 1P3537 Dial Bore Gauge Group can be used to check the size of the bores. Special Instruction, GMG00981 is with the group.

1P3537 Dial Bore Gauge Group

Projection Of Cylinder Liners

Check liner projection above the spacer plate as follows:

1. Make sure the top surface of the cylinder block, the liner bores, spacer plates and liner flanges are clean and dry.

2. Install a new gasket and spacer plate (5) on the cylinder block.

3. Install the cylinder liners in the cylinder block without seals or bands.

Measuring Liner Height Projection
(1) 3H0465 Plate. (2) Dial indicator. (3) 1P2402 Gauge Body. (4) 0S1575 Bolt. (5) Spacer plate. (6) 8B7548 Puller Assembly (Crossbar).

4. Hold the spacer plate and liner in position as follows:

a. Install four bolts (4) and washers around each cylinder liner as shown. Tighten the bolts evenly to a torque of 95 N·m (70 lb ft).

b. Install crossbar (6), plates (1) and the two 8F6123 Bolts. Be sure the crossbar is in position at the center of the liner and the liner surface is clean. Tighten the bolts evenly to a torque of 70 N·m (50 lb ft)

c. Check the distance from the bottom edge of crossbar (6) to the top edge of the spacer plate. The distance on each end of the crossbar must be the same.

5. Use 8T0455 Liner Projection Tool Group to measure liner projection.

6. To zero dial indicator (2), use the back of 1P5507 Gauge with dial indicator (2) mounted in 1P2402 Gauge Body (3).

7. Liner projection must be 0.059 to 0.199 mm (.0023 to .0078 in). Make the measurement to the outer flange of the liner, not the inner ring. The maximum difference between high and low measurements made at four places around each liner is 0.05 mm (.002 in).

NOTE: If liner projection changes from point to point around the liner, turn the liner to a new position within the bore. If still not within specifications, move liner to a different bore.

NOTE: When liner projection is correct, put a temporary mark on the liner and spacer plate so when the seals and band are installed, the liner can be installed in the correct position.

Flywheel And Flywheel Housing

Face Run Out (axial eccentricity) of the Flywheel Housing

8T5096 Dial Indicator Group Installed (Typical Example)

If any method other than given here is used, always remember bearing clearance must be removed to get correct measurements.

1. Fasten a dial indicator to the flywheel so the anvil of the indicator will touch the face of the flywheel housing.

2. Put a force on the crankshaft toward the rear before the indicator is read at each point.

Checking Face Runout Of The Flywheel Housing

3. With dial indicator set at "0" (zero) at location (A), turn the flywheel and read the indicator at locations (B), (C) and (D).

4. The difference between lower and higher measurements taken at all four points must not be more than 0.30 mm (.012 in), which is the maximum permissible face run out (axial eccentricity) of the flywheel housing.

Bore Runout (radial eccentricity) of the Flywheel Housing

1. Fasten the dial indicator as shown so the anvil of the indicator will touch the bore of the flywheel housing.

2. With the dial indicator in position at (C), adjust the dial indicator to "0" (zero). Push the crankshaft up against the top of the bearing. Write the measurement for bearing clearance on line 1 in column (C) in the Chart For Dial Indicator Measurements.

8T5096 Dial Indicator Group Installed

NOTE: Write the dial indicator measurements with their positive (+) and negative (-) notation (signs). This notation is necessary for making the calculations in the chart correctly.

3. Divide the measurement from Step 2 by 2. Write this number on line 1 in columns (B) & (D).

4. Turn the flywheel to put the dial indicator at (A). Adjust the dial indicator to "0" (zero).

5. Turn the flywheel counterclockwise to put the dial indicator at (B). Write the measurements in the chart.

Checking Bore Runout Of The Flywheel Housing

6. Turn the flywheel counterclockwise to put the dial indicator at (C). Write the measurement in the chart.

7. Turn the flywheel counterclockwise to put the dial indicator at (D). Write the measurement in the chart.

8. Add lines I & II by columns.

9. Subtract the smaller number from the larger number in line III in columns (B) & (D). The result is the horizontal eccentricity (out of round). Line III, column (C) is the vertical eccentricity.

10. On the graph for total eccentricity, find the point of intersection of the lines for vertical eccentricity and horizontal eccentricity.

11. If the point of intersection is in the range marked "Acceptable", the bore is in alignment. If the point of intersection is in the range marked "Not Acceptable", the flywheel housing must be changed.

Graph For Total Eccentricity

Face Runout (axial eccentricity) of the Flywheel.

1. Install the dial indicator as shown. Always put a force on the crankshaft in the same direction before the indicator is read so the crankshaft end clearance (movement) is always removed.

Checking Face Runout Of The Flywheel

2. Set the dial indicator to read "0" (zero).

3. Turn the flywheel and read the indicator every 90 degrees.

4. The difference between the lower and higher measurements taken at all four points must not be more than 0.15 mm (.006 in), which is the maximum permissible face runout (axial eccentricity) of the flywheel.

Bore Runout (radial eccentricity) of the Flywheel

1. Install the dial indicator (3) and make an adjustment of the universal attachment (4) so it makes contact as shown.

2. Set the dial indicator to read "0" (zero).

3. Turn the flywheel and read the indicator every 90 degrees.

4. The difference between the lower and higher measurements taken at all four points must not be more than 0.15 mm (.006 in), which is the maximum permissible bore runout (radial eccentricity) of the flywheel.

5. Runout (eccentricity) of the bore for the pilot bearing for the flywheel clutch, must not exceed 0.13 mm (.005 in).

Checking Bore Runout Of The Flywheel
(1) 7H1945 Holding Rod. (2) 7H1645 Holding Rod. (3) 7H1942 Indicator. (4) 7H1940 Universal Attachment.

Checking Flywheel Clutch Pilot Bearing Bore

Vibration Damper

Damage to or failure of the damper will increase vibrations and result in damage of the crankshaft.

If the damper is bent or damaged, or if the bolt holes in the damper are loose fitting, replace the damper. Replacement of the damper is also needed at the time of a crankshaft failure due to torsional forces.

Electrical System

Test Tools For Electrical System

Most of the tests of the electrical system can be done on the engine. The wiring insulation must be in good condition, the wire and cable connections must be clean and tight, and the battery must be fully charged. If the on-engine test shows a defect in a component, remove the component for more testing.

The service manual Testing And Adjusting Electrical Components, REG00636 has complete specifications and procedures for the components of the starting circuit and the charging circuit.

4C4911 Battery Load Tester

The 4C4911 Battery Load Tester is a portable unit in a metal case for use under field conditions and high temperatures. It can be used to load test all 6, 8 and 12V batteries. This tester has two heavy-duty load cables that can easily be fastened to the battery terminals. A load adjustment knob on the top permits the current being drawn from the battery to be adjusted to a maximum of 1000 amperes. The tester is cooled by an internal fan that is automatically activated when a load is applied.

The tester has a built in LCD digital voltmeter and amperage meter. The digital voltmeter accurately measures the battery voltage at the battery through tracer wires buried inside the load cables. The digital amperage meter accurately displays the current being drawn from the battery under test.

NOTE: Make reference to Operating Manual, SEHS9249 for more complete information for use of the 4C4911 Battery Load Tester.

6V7070 Heavy-Duty Digital Multimeter

The 6V7070 Heavy-Duty Digital Multimeter is a completely portable, hand held instrument with a digital display. This multimeter is built with extra protection against damage in field applications, and is equipped with seven functions and 29 ranges. The 6V7070 Multimeter has an instant ohms indicator that permits continuity checks for fast circuit inspection. It also can be used for troubleshooting small value capacitors.

The 6V7800 Regular-Duty Digital Multimeter (a low cost option to the Heavy-Duty Multimeter) is also available; however, the 6V7800 Multimeter does not have the 10A range or the instant ohms feature of the 6V7070 Multimeter.

NOTE: Make reference to Special Instruction, SEHS7734 for more complete information for use of the 6V7070 and 6V7800 Multimeters.

Battery

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Never disconnect any charging unit circuit or battery circuit cable from battery when the charging unit is operated. A spark can cause an explosion from the flammable vapor mixture of hydrogen and oxygen that is released from the electrolyte through the battery outlets. Injury to personnel can be the result.

Before any testing is done on the electrical system, the batteries should be checked for good connections and must be at least 75 percent (1.225 Sp Gr) fully charged.

The battery circuit is an electrical load on the charging unit. The load is variable because of the condition of the charge in the battery. Damage to the charging unit will result if the connections (either positive or negative) between the battery and charging unit are broken while the charging unit is in operation. This is because the battery load is lost and there is an increase in charging voltage. High voltage will damage, not only the charging unit, but also the regulator and other electrical components.

Use the 4C4911 Battery Load Tester to load test a battery that does not hold a charge when in use. Refer to Operating Manual, SEHS9249 for more detailed instructions on use of the 4C4911 Battery Load Tester. See Special Instruction, SEHS7633 for the correct procedure and specifications to use when testing batteries.

Charging System

The condition of charge in the battery at each regular inspection will show if the charging system operates correctly. An adjustment is necessary when the battery is constantly in a low condition of charge or a large amount of water is needed (more than one ounce of water per cell per week or per every 100 service hours).

When it is possible, make a test of the charging unit and voltage regulator on the engine, and use wiring and components that are a permanent part of the system. Off-engine (bench) testing will give a test of the charging unit and voltage regulator operation. This testing will give an indication of needed repair. After repairs are made, again make a test to give proof that the units are repaired to their original condition of operation.

To check for correct output of the alternator, see the Specifications module.

Before the start of on-engine testing, the charging system and battery must be checked as shown in the Steps that follow:

1. Battery must be at least 75 percent (1.225 Sp Gr) fully charged and held tightly in place. The battery holder must not put too much stress on the battery.

2. Cables between the battery, starter and engine ground must be the correct size. Wires and cables must be free of corrosion and have cable support clamps to prevent stress on battery connections (terminals).

3. Leads, junctions, switches, and panel instruments that have direct relation to the charging circuit must give correct circuit control.

4. Inspect the drive components for the charging unit to be sure they are free of grease and oil and have the ability to operate the charging unit.

Alternator Regulator

When an alternator is charging the battery too much or not enough, the charging rate of the alternator should be checked. Make reference to the Specifications module to find all testing specifications for the alternators and regulators.

Alternator
(1) Ground terminal. (2) Pulley nut.

No adjustment can be made to change the rate of charge on the alternator regulators. If rate of charge is not correct, a replacement of the regulator is necessary.

Alternator Pulley Nut Tightening

Tools To Tighten Alternator Pulley Nut
(1) 8T9293 Torque Wrench. (2) 8S1588 Adapter (1/2 inch female to 3/8 inch male). (3) 2P8267 Socket Assembly. (4) 8H8517 Combination Wrench (1 1/8 inch). (5) 8T5314 Socket.

Tighten nut that holds the pulley to a torque of 100 ± 7 N·m (75 ± 5 lb ft) with the tools shown.

Starting System

Use the multimeter in the DCV range to find starting system components which do not function.

Move the start control switch to activate the starter solenoid. Starter solenoid operation can be heard as the pinion of the starter motor is engaged with the ring gear on the engine flywheel.

If the solenoid for the starter motor will not operate, it is possible that the current from the battery did not get to the solenoid. Fasten one lead of the multimeter to the connection (terminal) for the battery cable on the solenoid. Put the other lead to a good ground. A zero reading is an indication that there is a broken circuit from the battery. More testing is necessary when there is a voltage reading on the multimeter.

The solenoid operation also closes the electric circuit to the motor. Connect one lead of the multimeter to the solenoid connection (terminal) that is fastened to the motor. Put the other lead to a good ground. Activate the starter solenoid and look at the multimeter. A reading of battery voltage shows the problem is in the motor. The motor must be removed for further testing. A zero reading on the multimeter shows that the solenoid contacts do not close. This is an indication of the need for repair to the solenoid or an adjustment to be made to the starter pinion clearance.

Make a test with one multimeter lead fastened to the connection (terminal) for the small wire at the solenoid and the other lead to the ground. Look at the multimeter and activate the starter solenoid. A voltage reading shows that the problem is in the solenoid. A zero reading is an indication that the problem is in the start switch or the wires for the start switch.

Fasten one multimeter lead to the start switch at the connection (terminal) for the wire from the battery. Fasten the other lead to a good ground. A zero reading indicates a broken circuit from the battery. Make a check of the circuit breaker and wiring. If there is a voltage reading, the problem is in the start switch or in the wires for the start switch.

A starter motor that operates too slow can have an overload because of too much friction in the engine being started. Slow operation of the starter motor can also be caused by a short circuit, loose connections and/or dirt in the motor.

To check for correct output of starter motors and starter solenoid, see the Specifications module.

Pinion Clearance Adjustment

When the solenoid is installed, make an adjustment of the pinion clearance. The adjustment can be made with the starter motor removed.

Typical Connection for Checking Pinion Clearance
(1) Connector from MOTOR terminal on solenoid to motor. (2) SW terminal (3) Ground terminal.

1. With the solenoid installed on the starter motor, remove connector (1).

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

3. Connect the other side of the battery to ground terminal (3).

4. Connect for a moment a wire from the solenoid connection (terminal) marked MOTOR to the ground connection (terminal). The pinion will shift to crank position and will stay there until the battery is disconnected.

Typical Pinion Clearance Adjustment
(4) Shaft nut. (5) Pinion. (6) Pinion clearance.

5. Push the pinion toward the commutator end to remove free movement.

6. Pinion clearance (6) must be 8.3 to 9.9 mm (.33 to .39 in).

7. To adjust pinion clearance, remove plug and turn nut (4).

8. After the adjustment is completed, install the plug over adjustment nut (4) and install connector (1) between the MOTOR terminal on the solenoid and the starter motor.

Air Starting System

Pressure Regulating Valve

Pressure Regulating Valve (Typical Illustration)
(1) Adjustment screw. (2) Regulator inlet. (3) Regulator outlet.

Use the procedure that follows to check and adjust the pressure regulating valve.

1. Drain the line to the pressure regulating valve or drain the air storage tank.

2. Disconnect the regulator from the starter control valve.

3. Connect an 8M2885 Pressure Gauge to the regulator outlet.

4. Put air pressure in the line or tank.

5. Check the pressure.

6. Adjust the pressure regulating valve to 690 to 1030 kPa (100 to 150 psi).

7. Remove the air pressure from the line or tank.

8. Remove the 8M2885 Pressure Gauge and connect the air pressure regulator to the line to the air starting motor.

Each engine application will have to be inspected to get the most acceptable starting results. Some of the factors that affect regulating valve pressure setting are: attachment loads pulled by engine during starting, ambient temperature conditions, oil viscosity, capacity of air reservoir and condition of engine (new or worn).

The advantages of setting the valve at the higher pressures are increased torque for starting motor and faster rotation of engine. The advantage of setting the valve at the lower pressures is longer time of engine rotation for a given reservoir capacity of supply air.

Lubrication

Always use an air line lubricator with these starters.

For temperatures above 0°C (32°F), use a good quality SAE 10 motor oil without detergent.

For temperature below 0°C (32°F), use diesel fuel.

To maintain the efficiency of the starting motor, flush it at regular intervals. Put approximately 0.5 liter (1 pt) of diesel fuel into the air inlet of the starting motor and operate the motor. This will remove the dirt, water and oil mixture (gummy coating) from the vanes of the motor.