2-4. ENGINE TROUBLESHOOTING (CONT)
TEST OR INSPECTION
13. DIFFERENCE BETWEEN TWO OR MORE CYLINDER COMPRESSION VALUES MORE THAN 25 PSIG
WHEN PERFORMING CYLINDER COMPRESSION TEST (PAGE 3-12).
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, go to step 2 be-
Step 2. Remove cylinder heads (page 3-45).
Check for carbon deposits on cylinder head and piston crown.
a. If carbon deposits are present, remove from cylinder head and
valve heads using power driven wire brush.
Dry cleaning solvent P-D-680 used to clean parts is toxic and flammable.
Wear protective goggles and gloves and use only in a well ventilated
area. Avoid contact with skin, eyes and clothes and donut breathe
Do not use near open flame or excessive heat and don-t smoke
when using it. Failure to do so could cause serious injury. If you be-
come dizzy while using cleaning solvent, get fresh air and medical
attention immediately. If contact with skin or clothes is made, flush
with large amounts of water.
If contact with eyes is made, wash eyes
with water and get medical aid immediately.
Remove residue using cleaning solvent P-D-680 and clean cloths.
Compressed air used for cleaning purpose will not exceed 30 psi. Use
only with effective chip guarding and personal protective equipment
(goggles/shield, gloves, etc). Failure to do so could cause serious
injury to eyes and possible blindness.
If you hurt your eyes or if a
foreign object is blown into your eyes, seek medical attention
Remove carbon from piston crown in same manner as above. Use
compressed air to remove residue from cylinders.