TM 5-6115-584-34
NAVFAC P-8-622-34
TO-35C2-3-456-2
TM-0568C-34
Table 2-3. Troubleshooting (Cont)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
13. METALLIC KNOCKING, CLICKING, OR POUNDING FROM CRANKCASE OR CYLINDER BLOCK.
Step 1. Check for worn or loose connecting rod bearings (paragraph 7-10).
Replace bearings if necessary.
Step 2. Check for loose piston and connecting rod assembly (paragraph 7-10).
Repair or replace assembly.
14. LOW ENGINE COMPRESSION.
Step 1.
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Step 7.
NOTE
Normal cylinder pressure is between 350 and 450 psi depend-
ing upon engine condition. Maintenance should be considered
if pressure is below 325 psi or if there is a 15 percent or
more difference between cylinders.
Check for loose cylinder head (paragraph 7-9).
Properly tighten head.
Check for leaky head gasket (paragraph 7-9).
Replace gasket.
Check for broken valve spring (paragraph 7-9).
Replace broken springs.
Check for sticking valves (paragraph 7-9).
See sticking valve section below.
Check for leaking valves (paragraph 7-9).
Clean and, if necessary, regrind valves and valve seats.
Check for worn or sticking piston rings (paragraph 7-10).
Replace rings if necessary. Check condition of cylinder walls.
Check for worn cylinder walls and pistons (paragraphs 7-10 and 7-19).
Refinish cylinder walls. Repair or replace pistons.
15. STICKING VALVES.
Step 1. Check for dirty, scored, or gummy valve stems or guides (paragraph 7-9).
Clean stems and guides. If necessary, replace guides.
Step 2. Check for weak or broken springs (paragraph 7-9).
Replace springs.
2-9
