TM 5-4320-302-14
Table 6-1. General Support Maintenance Troubleshooting - Continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 2.
Check for scored cylinders or pistons. Inspect cylinders (para 6-8). Inspect pistons (6-16).
Repair or replace faulty cylinder head assembly (para 6-8) and piston (para 6-16).
Step 3.
Check for loose piston pin circlips. Inspect piston pin circlips (para 6-16).
Replace a loose piston pin circiip (para 6-16).
Step 4.
Check for piston and connecting rod alinement. Inspect pistons (para 6-16) and connecting rods
(para 6-17). Check crankshaft thrust surfaces for wear or grooving (para 6-18).
Replace a faulty piston (para 6-16) or connecting rod (para 6-17). If necessary, replace
crankshaft (6-18).
3.
ENGINE PRODUCES EXCESSIVE CRANKCASE PRESSURE
Step 1.
Check for worn piston rings, a hole or crack in a piston crown, or excessive exhaust back pressure.
Replace worn or damaged parts (para 6-16).
4.
ENGINE HAS LOW OIL PRESSURE
Step 1.
Check for clogged lube oil cooler. Inspect lube oil cooler (para 5-14).
Replace a clogged or otherwise faulty lube oil cooler (para 5-14).
Step 2.
Check for partially clogged oil suction pipe inlet screen. Inspect oil suction pipe inlet screen (para 6-
11).
Replace an oil suction pipe that is damaged or cannot be cleaned adequately (para 6-11).
Step 3.
Check for air leak in oil suction pipe. Inspect oil suction pipe (para 6-11).
Replace a faulty oil suction pipe (para 6-11).
Step 4.
Check for worn or damaged lube oil pump. Inspect lube oil pump (para 6-11).
Repair or replace a faulty lube oil pump (para 6-11).
Step 5.
Check for excessive wear on crankshaft main bearing journals or bearings.
Inspect crankshaft (para 6-18). Inspect main bearings (para 6-18).
Replace faulty crankshaft or main bearings, if necessary (para 6-18).
6-3
