ARMY TM 9-2815-255-24
AIR FORCE TO 38G1-95-2
MARINE CORPS TM 2815-24/4
Replacement bearing caps are supplied with bearing bore unfinished.
Inspect piston cooling orifices as follows:
Inspect each cooling orifice to make sure it is not plugged or damaged.
Use a soft wire and compressed air to clean orifice. Replace, if condition is questionable.
A piston cooling orifice failure could cause damage to pistons, piston pins, rod pin bushings,
and liners. If a piston cooling orifice Is left out of block during assembly, low or no oil pressure
Install all the orifices and tighten to 84 in-lbs (10 Nm).
If crankshaft is to be reground, use following recommended guidelines.
Crankshaft grinding should be done only by experienced personnel on equipment capable of
maintaining crankshaft size and finish specifications.
If undersize bearings are used, check bearing clearance after bearing caps have been tightened
to specified torque. If undersize bearings are too tight and clearance Is not within specifications,
Journal and bearing will be wiped clean of all oil. This would result in premature wear of parts.
When grinding crankshaft, also grind fillet radii to specifications. This is necessary to prevent
stress risers in fillet areas during grinding.
NOTE In addition to standard size main and connecting rod bearings, 0.002, 0.010, 0.020, and
0.030 inch (0.05, 0.25, 0.51, and 0.76 mm) undersize bearings are available.
The 0.002 inch (0.05 mm) undersize bearings are used normally to compensate for slight even
wear on crankshafts. Regrinding is usually unnecessary when this size bearing is used.