TM 5-3805-262-34
2-4. ENGINE TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
4. ENGINE MISFIRES (Cont).
Step 4. Perform engine compression check (page 3-12).
a. If compression check readings are low, go to step 5 below.
b. If compression check readings are high, go to step 7 below.
c. If compression check readings are normal, go to step 8 below.
Step 5. Put a small amount of oil in cylinder and repeat engine compression
check (page 3-12).
a. If compression check readings are now normal, replace piston
rings (page 4-42).
b. If compression check readings are still low, go to step 6 below.
Step 6. Check valve timing (page 3-8).
a. If valve timing is not okay as indicated by dial indicator hand
not indicating 0.053 inch, go to Malfunction 11, page 2-41.
b. If valve timing is okay as indicated by dial indicator hand in-
dicating 0.053 inch, compression leakage is either past valves
or a damaged cylinder head gasket. Remove cylinder head (page
3-45) associated with bad cylinder and check gasket. If cylinder
head gasket is okay, remove and replace valves (page 3-74).
Step 7. Remove muffler (refer to TM 5-3805-262-20).
Repeat engine compression check (page 3-12).
a. If compression check readings are normal, problem was restricted
muffler. Replace muffler (refer to TM 5-3805-262-20).
b. If compression check readings are still high, there are exces-
sive carbon deposits in engine. Remove cylinder head (page 3-45)
associated with bad cylinder and remove carbon deposits from
cylinder sleeves (page 4-43). If carbon deposits are not pre-
sent, use micrometer and check cylinder head height. Replace if
head height is less than 4.080 inches (page 3-45).
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