Komatsu PC130-7, Shop Manual, Page: 339 / 342

PC130-7
20-623
TROUBLESHOOTING
Confirm recent repair history
Operated for long period
Check items
Questions
Degree of use of machine
Troubleshooting
Replace Replace Replace Replace Correct Replace Correct Replace Correct Replace Replace Replace
Remedy
When valve clearance is checked, it is found to be outside
standard value
Gradually occurred
Suddenly occurred
Blue under light load
Black
Metal particles are found in oil filter
Blow-by gas is excessive
Noise of interference is heard from around turbocharger
Engine pickup is poor and combustion is abnormal
Seal on injection pump has come off
Abnormal noise is loud when accelerating engine
Clanging sound is heard from around cylinder head
Leakage of air between turbocharger and cylinder head, loose clamp
Vibrating noise is heard from around muffler
When exhaust manifold is touched immediately after starting
engine, temperature of some cylinders is low
Remove cylinder head cover and inspect directly
When muffler is removed, abnormal noise disappears
Injection pump test shows that injection amount is incorrect
Fan is deformed, belt is loose
When compression pressure is measured, it is found to be low
When turbocharger is rotated by hand, it is found to be heavy
Remove gear cover and inspect directly
Speed does not change when operation of certain cylinders is
stopped
When control rack is pushed, it is found to be heavy, or does
not return
Condition of abnormal
noise
Non-specified fuel is being used
Engine oil must be added more frequently
Color of exhaust gas
Missing, seized bushing Sei
z
ed turbocharger
, interference
Excessiv
e
wear of piston ring, cylinder (liner less engine)
Clogged, seized injection no
zzle
Defective injection pump (rack, plunger seized)
Defective injection p
ump (excessive in
jection)
Deformed fan, fan belt interference D
efective adjustment of valve clearance
Broken
dynamic
valve syste
m
(valve,
roc
k
er
lever, etc.)
Improp
er gear tra
in backlash
L
eakag
e of air b
etween turb
ocharg
er and
cylinder hea
d
Defect insi
de m
uff
ler (
dividing board out of po
sition
)
Causes
S-15 Abnormal noise is made
a
Judge if the noise is an internal noise or an external
noise.
General causes why abnormal noise is made
• Abnormality due to defective parts
• Abnormal combustion
• Air sucked in from intake system
S-15
(1)