TOPIC 6. CRANKSHAFT AND CRANKSHAFT COMPONENTS

TM 10-3930-644-14&P

TOPIC 6. CRANKSHAFT AND CRANKSHAFT COMPONENTS

A. DESCRIPTION

14. Disconnect tube and hose from hydraulic pump

and reservoir. Remove capscrews and remove

The crankshaft translates the reciprocating motion of the

hydraulic pump. Remove pump drive gear and

connecting rods and pistons into a rotary motion. The

sleeve.

crankshaft is forged of a special heat treated steel and

15. Disconnect wires from water temperature

rifle drilled for pressure lubrication of the connecting rods

sender, oil pressure sender and neutral start

and main bearings. End thrust is controlled by flanges

switch.

on the center main bearing. The crankshaft timing gear

is meshed with the camshaft gear, and the camshaft

16. Ensure that all external connections to engine

gear, in turn, is meshed with the fan drive gear. The

have been disconnected.

crankshaft is sealed on each end by filler blocks with oil

17. Attach hoisting chain to engine, remove three

seals. The filler blocks are secured to front and rear of

motor

mount

capscrews,

disengage

the cylinder block. The main bearings are thin wall

transmission linkage, oil lines, and drive shaft at

shells held in place by precision machined bearing seats

universal joint.

and caps.

18. Remove engine and transmission assembly.

B. REMOVAL

19. Remove securing

bolts

and

transmission

assembly.

The following teardown procedure is recommended for

proper crankshaft removal.

20. Remove flywheel by first removing the six bolts

that attach the flywheel to the crankshaft. These

bolts are special and should not be mixed with

1. Drain radiator, cylinder block, and oil pan.

any others.

2. Remove upper and lower radiator hoses and

21. Carefully rotate the entire engine, so that the oil

clamps. Remove transmission cooling lines if

pan faces up.

(If cylinder head has been

applicable.

removed, take care not to damage any extended

3. Disconnect water by-pass tube.

valves.)

4. Remove fan blade and water pump.

22. Remove oil pan capscrews and oil pan (Figure 6-1).

5. Disconnect and label attaching wires to

23. Remove front and rear filler blocks. Refer to

alternator, and remove mounting capscrews;

TOPIC 14. FILLER BLOCKS AND OIL GUARD.

remove alternator.

24. Remove fan drive pulley, drive adapter and shaft

6. Remove distributor, cable support bracket, and

and gear from gear cover.

spark plug wiring.

25. Remove governor and timing gear cover. Refer

7. Remove spark plugs, and cap or tape exposed

to TOPIC 18 or TOPIC 19.

spark plug ports.

26. Remove capscrew and remove pump coupling

8. Disconnect and label attaching wires to starter

(Figure 6-3). Pull crank gear from crankshaft

motor. Remove capscrews and carefully pull

(Figure 6-3). The crankshaft gear, which is a

starter free of housing.

press fit on the shaft, requires a puller. Remove

key.

9. Remove starter motor.

27. Drop the Mil pump, by removing nut holding

10. Disconnect from carburetor the governor rod

pump to center main bearing cap.

assembly, linkage, fuel line, and air intake hose.

28. Remove connecting rod cap nuts and bearing caps.

11. Remove capscrews securing intake/ exhaust

manifold, and remove manifold with attached

29. Remove main bearing cap bolts and bearing caps.

carburetor as a complete assembly.

30. Carefully lift the crankshaft (Figure 6-2) from the

12. Remove linkage to governor assembly.

bearing mountings. Avoid nicking or bumping

the bearing surfaces while handling

13. Remove oil filter lines at engine.

R-104-1

3-15