G343 ENGINE Caterpillar


Testing And Adjusting

Usage:

Problem Solving

Index

1. Engine Fails to Start
2. Misfiring
3. Stalls at Low Speed
4. Erratic Engine Operation
5. Lack of Power
6. Excessive Vibration
7. Valve Train Clicking Noise
8. Oil in Coolant
9. Mechanical Knock
10. Excessive Gas Consumption
11. Loud Valve Train Noise
12. Excessive Valve Lash
13. Valve Rotator or Spring Retainer Free
14. Slobber
15. Valve Lash Close-up
16. Premature Engine Wear
17. Coolant in Engine Lubricating Oil
18. Low Engine Oil Pressure
19. High Lubricating Oil Consumption
20. Abnormal Engine Coolant Temperature
21. Starting Motor Fails to Crank
22. Alternator or Generator Fails to Charge
23. Alternator or Generator Charging Rate Low or Unsteady
24. Atlernator or Generator Charging Rate Excessive
25. Noisy Alternator or Generator
26. Short Spark Plug Life
27. Pre-Ignition
28. Surging
29. Detonation
30. Gas Supply Line Safety Shut-off Valve Fails to Close
31. Instrument Panel Gauge Switches Fail to Stop Engine
32. Instrument Panel Gauge Switches Prevent Engine Start
33. Overspeed Contactor Switch Fails to Signal Shutoff
34. Overspeed Contactor Switch Signals Shutoff at Low Speed

Gas, Air Induction And Exhaust Systems

Restriction Of Air Inlet And Exhaust

Engine horsepower and efficiency will be reduced if either the air inlet or exhaust system becomes restricted.

The air cleaner should not restrict air flow more than 30 in. (762 mm) of water difference in pressure.

Exhaust back pressure (pressure difference measured between the turbocharger outlet elbow tap and ambient air) should be no more than 15 in. (381 mm) of water. Back pressure for naturally aspirated engines, should be no more than 25 in. (635 mm) of water, measured between exhaust outlet and ambient air.

Crankcase Pressure

Crankcase pressure (difference from ambient) above 3 in. (76,2 mm) of water is excessive and can be a result of combustion gas leaking past broken or damaged pistons and/or piston rings. This condition will usually be accompanied by irregular engine operation and excess fumes from crankcase breather opening. This condition can cause the breather element to become restricted in an unusually short time. In addition, excessive pressure can cause engine oil to leak past gaskets and seals that would function properly under normal conditions.

Compression

Irregular (rough) engine operation can be caused by improperly adjusted or leaky valves. Operate the engine at RPM which makes the malfunction most pronounced. A non-firing or low compression cylinder can be located by removing spark plug wires one at a time. Continue this until a removed wire makes little or no difference in the engine operation. This same test can also indicate faulty spark plugs so further checking of the cylinder is necessary.

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

The following procedure provides a more complete check of the sealing ability of the individual valves without removing the cylinder head:

1. Remove the spark plug with 1P7424 Spark Plug Socket leaving the spark plug adapter in place.

2. Adapt an air hose to the spark plug adapter. This can be done with either a threaded fitting or by holding a rubber adapter in place.

3. Rotate the crankshaft until the piston in the suspected cylinder is at top center (TC) on the compression stroke. In this position the valves of the cylinder are closed.

4. Force air into the cylinder and then check for escaping air. Air escaping from the exhaust opening indicates exhaust valve leakage. Air escaping from the air cleaner inlet indicates inlet valve leakage. If air escapes from the crankcase breather during this test, the piston, rings and/or liner can be at fault.

On turbocharged engines, it may be necessary to remove inlet and outlet connections on both sides of turbocharger to notice leakage.

Performance Evaluation-Turbocharged Engines

When an engine is suspected of lacking power, it is sometimes desirable to make a quick instrument check to determine the approximate horsepower.

The 4S6553 Instrument Group provides a means to make this quick check. This group contains an instantaneous reading tachometer and a gauge for reading inlet manifold pressure. Instructions FEO36044 included with this group, explain the testing procedure.


4S6553 INSTRUMENT GROUP
1-Lid. 2-4S6997 Manifold Pressure Gauge. 3-Pressure tap fitting. 4-4S6992 Differential Pressure Gauges. 5-4S6991 Tachometer. 6-Zero adjustment screws. 7-8M2743 Gauge.

Satisfactory evaluation from the instruments and test procedure is dependent upon the engine operating adjustments being correct.

By checking inlet manifold pressure, and comparing that pressure with the RACK SETTING INFORMATION, determination can be made if an engine is operating efficiently. This test should be used if engine horsepower seems to be too low, yet no specific symptom of engine trouble is apparent.

Line Pressure Regulator

A line pressure regulator is required if the engine is turbocharged, or if the fuel supply pressure is exceptionally high.


CHECKING LINE PRESSURE REGULATOR ADJUSTMENT (Schematic Diagram for Turbocharged Engine)
A-Pressure differential. 1-Bottom port. 2-Adjustment screw. 3-Gas supply at carburetor. 4-Water manometer. 5-Valve.

1. Line pressure regulator adjustment can be checked with either the 4S6553 Instrument Group or a water manometer while engine is running.

2. Attach one end of a water manometer (4) to the gas supply at carburetor (3). On turbocharged engines, attach the other end of the manometer to the bottom port (1) of the line pressure regulator as shown, to measure the pressure differential (A). On naturally aspirated engines, attach the manometer only at (3) and leave the other end open to the atmosphere.

3. Remove the cap and turn screw (2) until the value (A) is within the specified range. Natural Gas: 5 1/2 in. (139,7 mm); Propane: 1 in. negative (2,54 mm).

NOTE: The valve (5) should be closed before the engine is stopped. This will prevent the manometer fluid from being drawn into the inlet of the carburetor (3).

Cylinder Head

Use a 1P5559 Wrench to remove and install the spark plug adapters. Coat bore in head and seal with liquid soap. Coat threads with 9M3710 Anti-Seize Compound.

Camshaft Installation

1. Extreme caution should be exercised to be sure that all the camshaft followers are adjusted to provide maximum clearance before installation of the camshafts.

2. Rotate the crankshaft until No. 1 cylinder is at top center on the compression stroke.

3. Position the camshaft phasing gear timing marks (1) together and in a horizontal plane as shown.


CAMSHAFT PHASING GEARS
1-Timing marks.

4. Install the camshaft assembly.

5. Install the cam driveshaft with the blind spline on top.

6. Adjust the valve clearance.

Valve Clearance Setting

Refer to Lubrication and Maintenance Procedures for details of valve clearance adjustment.

Pressure Differential Regulator

The regulator has two .25 in. (6,4 mm) spacers (3) for altitude adjustment. Both spacers should be used for operation up to 1500 feet (457,2 m) altitude. Remove one for operating between 1500 and 4000 feet (457,2-1219,2 m). A slight amount of adjustment can be made by adding or removing shims (9). The regulator assembly bolts should be sealed at assembly.


REGULATOR
1-Measurements for testing regulator. 2-Pressure sensing port connection. 3-Spacers. 4-Bypass valve. 5-Breather location. 6-Bypass passage. 7-Turbine housing. 8-Diaphragm. 9-Shims.

To test the regulator with both spacers (3) in place, and atmospheric pressure in spring compartment, apply 30.18 PSI (211,5 kg/cm2) to pressure chamber through connection (2). Measurement at (1) should be less than 2.893 in. (73,48 mm). A second pressure setting of 7.74 PSI (0,5 kg/cm2) should result in a measurement at (1) of 2.893-2.983 in. (73,48-75,77 mm).

NOTE: Information in Form FEO34610 shows equipment for testing and adjusting this regulator.

Carburetor

Carburetor and governor linkage adjustments are covered in the topic GOVERNOR.

Turn the power mixture adjustment to center between "R" (rich) and "L" (lean). Make fuel mixture adjustments by changing the gas pressure from the line pressure regulator.


CARBURETOR ADJUSTMENTS (Carburetor removed for better illustration)
1-Idle adjustment screw. 2-Throttle stop screw.

Turn idle adjustment screw (1) four full turns open (from the closed position).

Turn throttle stop screw (2), to obtain desired idle speed. Recommended low idle is 465-485 RPM. (1200-1250 RPM when used with an electric set).

Cooling System

The engine has a pressurized cooling system. Pressurizing the cooling system serves two purposes. First, it permits safe operation at coolant temperature higher than the normal boiling point; thereby, providing a margin of cooling for those intermittent peak loads. Secondly, it prevents cavitation in the water pump and reduces the possibility of air or steam pockets forming in the coolant passages.

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

Visual Inspection

1. Check coolant level.

2. Inspect for leaks in the system.

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

4. Check fan belts.

5. Check for damaged fan blades.

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

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

Testing Cooling System

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

Temperature Gauge

2F7112 Thermometer or9S9102 Thermister Group.6B5072 and 8B2664 Bushings.

If overheating and loss of coolant is a problem, a pressure loss in the system could be the cause. If an overheating condition is indicated on the temperature gauge and loss of coolant is not evident, check the accuracy of the temperature gauge. Make this check by installing a 2F7112 Thermometer, using 8B2664 and 6B5072 Bushings, into the temperature regulator housing. The 9S9102 Thermister Group can be used in place of the thermometer.


THERMOMETER INSTALLED


NOTICE

Use CAUTION when working around an engine if it is running.


Start the engine. Partially cover the radiator or reduce flow of water to reduce cooling. The instrument panel temperature gauge contacts should be adjusted so the indicator just touches the contact at 210° F (99° C).


INSTRUMENT PANEL WATER TEMPERATURE GAUGE
1-Adjustment screw.

Pressure Cap

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

Water Temperature Regulator

The opening temperature of the regulator (bench test in atmospheric pressure) is approximately 165 ± 1° F (74 ± 1° C). The regulator should be fully opened at approx. 185°F (85°C).

Governor

Governor Adjustments


NOTICE

- Only competent personnel should attempt to adjust the low and high idle RPM. The low and high idle RPM settings for this engine are listed in the RACK SETTING INFORMATION.


Engine RPM should be checked with a 9M478 Electrical High Tension Tachometer or 4S6553 Engine Test Kit.

High Idle Adjustment

9M478 Electrical High Tension Tachometer or4S6553 Engine Test Kit.

High idle RPM can be adjusted by removing the cover (1) at the rear of the governor, and turning the high idle adjusting screw (3). Turning adjusting screw in a clockwise direction will decrease the idle RPM. The retainer hole in the cover (1) is shaped to prevent the screw from turning, after the adjustment has been made.


GOVERNOR ADJUSTMENTS
1-Cover. 2-Retainer hole. 3-High idle adjusting screw.

After setting the idle RPM, move the governor control lever to change the engine RPM. Return it to the idle position and recheck the idle RPM. Repeat the adjustment procedure until the specified idle RPM is obtained.

Low idle speed adjustment is made at the carburetor.

Linkage Adjustment

1P2385 Protractor Tool.

The linkage should be properly adjusted before any governor adjustments are made. Use of 1P2385 Protractor Tool is recommended.


LINKAGE ADJUSTMENT Dimensions in inches (mm)
1-Cross shaft levers. 2-Carburetor lever. 3-Linkage rods. 4-Governor lever.

Check to be sure the carburetor throttle plate shaft lever (2) is secured to the shaft at the angle shown from vertical when the throttle plate is closed. The lever should be pinned in position with a 2/0 x 1 taper pin.

Adjust the length of linkage rods (3) so the angles at carburetor lever (2) and governor lever (4) are maintained and the cross shaft levers (1) make the angles from horizontal as shown.

NOTE: Governor lever in shutoff position and throttle plate closed.

Illustrated here are three basic usages of the 1P2385 Protractor Tool.

First-Vertical housing face-to-lever angle.Second-Horizontal or level-to-lever angle.Third-Lever-to-lever angle.


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

Solid State Ignition

Test the solid state magneto in the same manner as any other magneto, by the intensity of the spark at the spark plug. When testing, remember that the magneto output is effected by the condition of the instrument panel components-magnetic switch, stop switch, oil pressure gauge and water temperature gauge. An overspeed shutoff contactor, and/or gas line solenoid valve connected with the magneto could cause an indication of magneto malfunction.

Timing Magneto To Engine

1. Remove the timing pointer cover from the flywheel housing.

2. Rotate crankshaft in direction of engine rotation until No. 1 piston is coming up on compression stroke.

3. Continue rotating crankshaft until desired timing mark appears directly under flywheel pointer. See Chart of Instructions for Timing Magneto for various conditions such as gas used and compression ratio.

NOTE: After top center (ATC) timing, with engine stopped, is required under some conditions. When earlier flywheels without ATC calibrations are encountered, mark the flywheel .998 in. (27,34 mm) on outside diameter of flywheel for each 5°.


FLYWHEEL TIMING MARKS (Viewed from right side of engine)
1-Flywheel pointer. 2-Calibrations after top center (ATC). 3-Calibrations before top center (BTC).

4. Position the magneto drive slots in proper position for timing. The drive coupling can be pulled out, then positioned and pushed into engagement.

5. With magneto off the engine, remove timing bolt (4) and rotate magneto drive until yellow mark (drilled hole) on pulser gear appears in center of opening.


DRIVE TANG AND DRIVE SLOT POSITIONS (Viewed from the rear of the engine. Drive slot approximately 60° from vertical, drive tang at 30° from magneto center line.)

6. Install the magneto. The drive tang and slot should engage.


SOLID STATE MAGNETO
4-Timing bolt.

7. Make final timing adjustment by rotating the magneto at the drive housing mounting and with the use of a timing light when the engine is running at rated speed.

Ignition Transformer

The transformer posts are indicated as positive (+) and negative (-). Transformers for all cylinders have positive (+) posts connected to the magneto plug connector with a wire connected at the connector marked G.

Firing Order

The firing order is 1-5-3-6-2-4. The wiring diagram shows the connection of each transformer to the pin connector at the magneto.

Spark Plugs And Adapters

1P5559 Wrench.1P1790 Firing Indicator.1P7424 Spark Plug Socket

If the spark plug adapter is incorrectly seated, water leakage or detonation and pre-ignition can occur. Adapters are installed and removed with use of an 1P5559 Wrench.

Spark plug firing voltage will vary with the spark plug condition and engine load. A new spark plug in an idling engine will take from 3,000 to 6,000 volts to fire. At full load, this voltage will increase to 8,000 to 10,000 volts. When the spark plug is worn to the regap time interval, the firing voltage will be over 10,000 volts. Running the plugs past regap time, will cause firing voltage to go even higher. When the spark plug requirements exceed this value, that spark plug begins to fire erratically.

Spark plug gap should be maintained at .013 to .015 in. (0,335-0,385 mm). The use of 1P1790 Firing Indicator can assist in solving ignition problems. Follow the instructions included with the tool.

Install spark plug adapters to a torque of 70 ± 5 lb. ft. (9,7 ± 0,7 mkg). Spark plugs should be installed to a torque of 18 lb. ft. (2,5 mkg). Spark plugs are removed and installed with 1P7424 Spark Plug Socket.

Gauge Contact Point Adjustment

The oil pressure gauge contact should be adjusted to shut down the engine at 8 PSI (0,56 kg cm2) oil pressure. Water temperature gauge contact should be adjusted to shut down the engine at 210° F (99° C).

Both gauges adjust in the same manner. Position the adjusting screw so the indicator just touches it at the required value.


WATER TEMPERATURE GAUGE
1-Adjustment screw.

Starting And Charging Systems

Most of the electrical system testing can be performed on the engine. The wiring insulation must be in satisfactory condition, the wire and cable connections both clean and tight and the battery fully charged. An "on-engine" test that indicates a defective component usually requires component removal for further testing.

The wire size, color and recommended length is provided in the topic WIRING DIAGRAM.

Battery

9S1990 BATTERY CHARGER TESTER.

The storage battery circuit represents a continuous, although variable, electrical load to the charging unit. If the circuit, positive or negative is opened or broken while the charging unit is charging, the loss of the battery load will result in the charging voltage rising to unsafe levels.

High voltage will damage the charging unit and regulator and may damage other electrical components or instruments.

NEVER DISCONNECT ANY CHARGING UNIT CIRCUIT OR BATTERY CIRCUIT CABLE FROM BATTERY WHEN THE CHARGING UNIT IS PRODUCING A CHARGE.

A load test should be made on a battery that discharges very rapidly when in use. To do this apply a resistance of (for 6 volt-two times and for 12 volt-three times) the ampere/hour rating of the battery across the battery main terminals. Allow the resistance to discharge the battery for 15 seconds and immediately test the battery voltage. A 6 volt battery in good condition will test 4.5 volts; a 12 volt battery in good condition will test 9 volts.

The instructions included with the 9S1990 Battery Charger Tester covers completely the battery testing subject.

Charging System

The condition and state of charge of the battery at each regular inspection will indicate if the charging system is operating efficiently. An adjustment is necessary when the battery is always in a low state of charge or an excessive amount of water must be added to the battery (more than one ounce of water per cell per week or per every 50 service hours).

Charging units and voltage regulators should be tested on the engine when possible, using wiring and accessories that are a permanent part of the system. Bench testing will provide the technician with an operational test of the charging unit or voltage regulator. Pre-repair testing will advise the depth of needed repairs. Final testing will prove the units are restored to their original operating efficiency.

Before starting the on-engine test the charging system and battery must be checked as stated in the following steps to eliminate possible difficulty.

1 Battery must be at least 75% (1.240 Sp. Gr.) full charged and properly secured in the carrier. The carrier must not place excessive physical strain on the battery.

2 Cables between the battery, starter and engine ground must be of recommended wire size. Wires and cables must be free of corrosion with cable supporting clamps to reduce strain on battery posts.

3 Leads, junctions, switches and panel instruments that are directly related to the charging circuit must be good enough to provide proper circuit control.

4 Inspect the crankshaft pulley, charging unit pulleys and drive belts to be sure they are free of grease and oil and are capable of driving the charging unit load.

Voltage Regulator Adjustment


Generator output adjustments are made by turning the spring tension adjustment screws of the generator regulator.

When a generator is either overcharging or is not charging enough, a generator regulator tester can be used to determine whether the voltage regulator control, or the current limiter control, or both, require adjustment. To obtain an accurate test, the regulator cover must not be removed and the regulator must be warmed to operating temperature.

The voltage regulator and the current limiter controls have a spring tension adjustment screw. To increase generator voltage or current, increase the spring tension on the respective control. Decrease spring tension to decrease generator output. After a regulator has been adjusted always test the generator output with the regulator cover installed.

Starting System

Use a D.C. voltmeter to locate starting system components which do not function.

Move starting control switch to energize the starter solenoid. Starter solenoid operation is audible as the starter motor pinion engages with the ring gear on the engine flywheel. The solenoid operation should also close the electric circuit to the motor. Attach one voltmeter lead to the solenoid terminal that is connected to the motor. Ground the other lead. Energize the starter solenoid and observe the voltmeter. A battery voltage reading indicates the malfunction is in the motor. It must be removed for further testing. No voltmeter reading indicates that the solenoid contacts do not close and the solenoid must be repaired or the starter pinion clearance should be adjusted to .36 in. (9,14 mm).

A starting motor solenoid that will not operate may not be receiving battery current. Attach one lead of the voltmeter to the solenoid battery cable connection. Ground the other lead. No voltmeter reading indicates a faulty circuit from the battery. A voltmeter reading indicates further testing is necessary.

Continue the test by attaching one voltmeter lead to the starting motor solenoid small wire terminal and the other lead to ground. Observe the voltmeter and energize the starter solenoid. A voltmeter reading indicates that the malfunction is in the solenoid. No voltmeter reading indicates the starter switch or wiring is the fault.

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

A starting motor that operates too slow can be overloaded by excessive mechanical friction within the engine being started. Slow starting motor operation can also be caused by shorts, loose connections and/or excessive dirt within the motor.

Pinion Clearance Adjustment (Delco-Remy)

Whenever the solenoid is installed, the pinion clearance should be adjusted. The adjustment should be made with the starting motor removed.


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

Bench test and adjust the pinion clearance at installation of solenoid as follows:

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

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

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

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


PINION CLEARANCE ADJUSTMENT
4-Shaft nut. 5-Pinion. 6-Pinion clearance.

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

6. Pinion clearance (6) should be .36 in. (9,14 mm).

7. Adjust clearance by removing plug and turning shaft nut (4).

Basic Block

Cylinder Liners

7M4321 Adapter Plate.7M3977 Piston Ring Compressor.7M3978 Piston Ring Expander.8B7548 Push Puller (crossbar only).Three 3H465 Plates (from 8B7548 Push Puller).Four 3/4" NC Bolts 3 in. (76,2 mm) long.Two 3/4" NC Bolts 7 in. (177,8 mm) long.Eight 7M7875 Head Bolt Washers.1P5510 Liner Projection Tool Group.

Check liner height projection as follows:

A. Make certain that the top plate and the cylinder liner flange are clean.

B. Use four 3/4" NC bolts 3 in. (76,2 mm) long, with two 7M7875 Washers (head bolt washers) on each bolt to secure the top plate to the cylinder block. Place two bolts with washers on each side of the cylinder liner. Tighten the bolts evenly to 50 lb. ft. (6,9 mkg).


SECURING TOP PLATE TO CYLINDER BLOCK

NOTE: To avoid moving bolts and washers as each liner is checked, install two bolts with washers on the side of each cylinder liner, along the entire length of the top plate. This requires fourteen bolts and twenty eight washers. Tighten all bolts evenly to 50 lb. ft. (6,9 mkg).

C. Invert a 3H465 Plate from an 8B7548 Push Puller, in the center of the 7M4321 Adapter Plate. Center the 8B7548 Crossbar in the inverted 3H465 Plate. Using two 3/4" NC bolts 7 in. (177,8 mm) long and two 3H465 Plates, secure the crossbar to the cylinder block as illustrated. Tighten the bolts evenly to 50 lb. ft. (6,9 mkg). Distance from bottom edge of crossbar, to top face of cylinder block top plate, must be the same on both sides of cylinder liner.

D. Zero the indicator using the backside of the 1P5507 Gauge with the dial indicator (1) mounted in the 1P2402 Block (2). Measure projection in four places as shown. Projection should not vary over .001 in. (0,025 mm). The average of these readings for each cylinder should not vary more than .002 in. (0,051 mm) with adjacent cylinders.


MEASURING LINER HEIGHT PROJECTION
1-Dial indicator. 2-1P2402 Block.

NOTE: Measure and check the following dimension when installing new parts. With all dimensions correct, proceed with the above listed Steps.

a. Top plate thickness .5150 ± .0005 in. (13,08 ± 0,12 mm).

b. Top plate gasket thickness, .008 ± .001 in. (0,20 ± 0,05 mm). (All surfaces must be clean and dry when installing gasket.)

c. Cylinder liner flange thickness, .5255-.5265 in. (13,35-13,37 mm).

Connecting Rods And Pistons

Use 7M3978 Piston Ring Expander to remove or install piston rings.

Use 7M3977 Piston Ring Compressor to install piston into cylinder block.

Torque-turn-tighten the connecting rod bolt nuts in the following Step sequence.

Viscous Type Vibration Damper

The viscous type vibration damper can be tested to determine if it is functioning properly. When the engine speed is reduced gradually from high idle to 2/3 of high idle, the timing gear train noise may be more noticeable at some speed within this range if the damper is faulty.

The following test will indicate the condition of the damper.

1. Attach hooks (1) in the mounting bolt holes. Clamp round rod (4) to the damper machined side and tighten nuts (6) to prevent shifting in handling.

NOTE: Use care in handling to avoid changing the rod location in respect to the original mounting on the damper.

2. Support damper (2) between angle irons (5) on blocks (8). Angle iron edges and rod should have smooth contact areas.

3. Place washers (3) on the light side to balance level (7). Record the number of washers.

4. Stand damper on edge for 8 to 24 hours so the internal solid cast iron core can settle to the low side. Mark 6 o'clock (bottom) and 12 o'clock (top) locations on the damper.

5. Repeat Steps 2 and 3.


CHECKING VIBRATION DAMPER (Typical Illustration)
1-Hook. 2-Damper. 3-Washers. 4-Round rod. 5-Angle irons. 6-Flat washers and nuts. 7-Level. 8-Blocks.

6. Stand damper on edge at 12 o'clock mark for 8 to 24 hours.

7. Repeat Steps 2 and 3.

8. If balance washers have to be shifted between 6 to 12 o'clock locations in Step 3, the damper is in good condition. If the washers are continuously required at the same location, either 6 o'clock or 12 o'clock, it indicates the damper needs replacing because the iron core is not free to move but has become "locked up".

Flywheel & Flywheel Housing

Heat ring gear to install. Do not exceed 600° F. (315° C.). Install ring gear so chamfered portion of gear teeth face the starter pinion when flywheel is installed.

Checking Flywheel Housing Face Runout

Make tool setup from parts of 8S2328 Dial Test Indicator Group.


CHECKING FLYWHEEL HOUSING FACE RUNOUT
A-Bottom. B-Right side. C-Top. D-Left side.

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

2. Pry the crankshaft to rear before taking readings at each point.

3. With dial indicator set at .000 in. (0,0 mm) at point (A), rotate crankshaft and take readings at points (B), (C) and (D).

4. The difference between the lowest and highest readings taken at all four points should not exceed .008 in. (0,203 mm), which is the maximum permissible flywheel housing face runout.

Checking Flywheel Housing Bore Runout

Make tool setup from parts of 8S2328 Dial Test Indicator Group.

1. Fasten the dial indicator to the crankshaft flange and adjust it to read .000 in. (0,0 mm) when the anvil is touching bore at point (1).

2. Pry the crankshaft in such a manner to remove crankshaft main bearing clearance when taking readings at each point.

3. Rotate crankshaft and take readings at points (2), (3) and (4).

4. The difference between the lowest and highest readings taken at all four points should not exceed .008 in. (0.203 mm), which is the maximum permissible flywheel housing bore runout.


CHECKING FLYWHEEL HOUSING BORE RUNOUT
1-Bottom. 2-Right side. 3-Top. 4-Left side.

NOTE: If any method other than described here is used, always consider bearing clearances to obtain correct readings.

Checking Flywheel Face Runout

Make tool setup from parts of 8S2328 Dial Test Indicator Group.

1. Mount a dial indicator as shown and pry the crankshaft in the same direction before taking all readings so the end clearance is always in the same direction.

2. Set the dial indicator (3) to read .000 in. (0,0 mm).

3. Turn the flywheel and take readings every 90°.

4. The difference between the lowest and highest readings taken at all four points should not exceed .006 in. (0,152 mm), which is the maximum permissible flywheel face runout.


CHECKING FLYWHEEL FACE RUNOUT
1-8S2329 Base and 8S2327 Post. 2-7H1945 Holding Rod. 3-7H1942 Indicator.

Checking Flywheel Bore Runout

Make tool setup from parts of 8S2328 Dial Test Indicator Group.


CHECKING FLYWHEEL BORE RUNOUT
1-7H1945 Holding Rod. 2-8S2329 Base and 8S2327 Post. 3-7H1940 Universal Attachment. 4-7H1942 Indicator.

1. Mount the dial indicator (4) and adjust it so the universal attachment (3) contacts the flywheel bore as shown.

2. Adjust the dial indicator to read .000 in. (0,0 mm) then take readings every 90° around the flywheel.

3. The difference between the lowest and highest readings taken at all four points should not exceed .006 in. (0,152 mm), which is the maximum permissible flywheel bore runout. Flywheel clutch pilot bearing bore run out should not exceed .005 in. (0,127 mm).


CHECKING FLYWHEEL CLUTCH PILOT BEARING BORE
1-7H1945 Holding Rod (7H1654 Holding Rod in addition for aluminum or large diameter housings). 2-8S2329 Base and 8S2327 Post. 3-7H1940 Universal Attachment. 4-7H1942 Indicator.

Crankshaft Seal

Installation of the crankshaft front and rear seals requires the 9S8873 Tool Group and 9S8866 Seal Pilot, 9S8876 Locator, 9S8864 Pusher Plate, 9S8858 Nut, and 9S8865 Pusher Plate.


INSTALLING CRANKSHAFT REAR SEAL Specific instructions for installation are part of the tool group.

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