TM 5-3810-307-24-1-2
SYMPTOM
PROBABLE CAUSE
CORRECTIVE ACTION
a. Internal gasket leakage.
a. Replace head assembly and
4. Air getting into coolant
gasket/seal kit.
system (or coolant in air
system).
b. Internal casting porosity.
b. Replace air compressor.
5. Excessive blow-by.
a. Worn piston rings.
a. Replace piston assembly.
b. Worn or scored cylinder
b. Replace air compressor.
head bore.
c. Debris in piston ring sealing
c. Disassemble and clean.
area.
6. Excessive noise.
a. Internal relief valve cycling.
a. Correct fault in the crane's air
system.
b. Excessive piston ring wear.
b. Replace piston assembly.
c. Carbon buildup on head and
c. Disassemble and clean.
piston.
d. Piston pin worn.
d. Replace piston assembly.
e. Connecting rod worn.
e. Replace connecting rod
assembly.
f.
Loose connecting rod cap
f. Replace connecting rod
bolts.
assembly.
g.
Front or rear crankshaft
g. Replace crankshaft bearings.
bearing worn.
h.
Internal relief valve leakage.
h. Replace head assembly.
i.
Excessive crankshaft journal
i. Replace air compressor.
or throw pin wear.
a. Correct fault in the crane's air
7. Excessive oil consumption.
a.
Excessive duty cycle or
system.
excessively high pressure
operation.
b.
Worn piston rings.
b. Replace piston assembly.
c.
Restricted air intake
c. Replace head assembly.
passage.
d.
Worn or scored cylinder
d. Replace air compressor.
head bore.
8. External oil leak.
a.
Head gasket leakage.
a. Remove head and replace
gasket/seal kit.
b. Bottom cover leakage.
b. Replace sump plug (part of
gasket/seal kit).
c. Internal casting porosity.
c. Replace air compressor.
I-4 Change-1