ARMY TM 9-2815-252-24
AIR FORCE TO 38G1-92-2
Remove camshaft, refer to paragraph 3-29.1.
Remove crankcase door, refer to paragraph 3-20.2.1.
Oil pump does not need to be removed.
Remove oil pressure relief valve and strainer, refer to paragraph 3-21.1.
Remove pistons and connecting rods, refer to paragraph 3-30.1.
Using a suitable puller, remove crankshaft pinion gear (8, FIGURE 3-40). Remove key (9) from crankshaft (10).
Use two flywheel bolts in end of crankshaft and a bar to hold crankshaft.
Remove main bearing housing, refer to paragraph 3-32.1.
Gently withdraw crankshaft (10) through flywheel end of crankcase.
Remove two capscrews (11) securing center bearing upper housing (12) to lower housing (13). Remove both
housings (2 and 13) and bearings (14).
If necessary, remove two dowel pins (15) from lower housing (13).
Remove thrust bearings (16) from gear end of crankshaft (10).
3-33.2. Inspect and Measure.
Inspect all bearings for scoring or wear.
If connecting rod big end has been disassembled because of failure of bearing, oil passages in crankshaft must
be examined for obstruction and fragments of metal.
Replace thrust bearings if they are damaged or worn.
Check center bearing clearance using bearing gage (PLASTIGAGEPR1) as follows:
Place a piece of correct size bearing gage approximately 0.25 in. (6.35 mm) off center across full width of
one bearing shell.
Install bearing and torque bolts.
Ensure crankshaft Is not turned when bearing gage is In place, and all traces of It must be
removed before final assembly of bearings to prevent damage to crankshaft and bearings.
Remove bearing shell. Compare width of bearing gage against scale printed on bearing gage container.
Compare with values found in TABLE 3-7.
Using appropriate measuring devices, check components listed in TABLE 3-7 for wear. Replace components
that exceed maximum clearance.
Check crankshaft end play as follows:
Set a dial indicator so that actuating plunger makes contact with flywheel end face of crankshaft.
Push crankshaft firmly towards gear end of engine and zero indicator.
Push crankshaft firmly towards flywheel end of engine and check end play. This should be 0.0071 to
0.0149 in. (0.18 to 0.38 mm). End play is maintained by installing a single 0.0149 or 0.0197 in. (0.38 or
0.50 mm) aluminum shim behind bearing housing flange.