Komatsu PC130-7, Shop Manual

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20-618
PC130-7
TROUBLESHOOTING
Confirm recent repair history
Operated for long period
Check items
Questions
Degree of use of machine
Troubleshooting
Adjust Replace Replace Adjust Correct Correct Correct Adjust
Remedy
When exhaust manifold is touched immediately after starting engine,
temperature of some cylinders is low
Match mark on injection pump is misaligned
There is external leakage of fuel from engine
Engine oil level rises and smells of diesel fuel
Engine low idling and high idling speeds are high
Seal on injection pump has come off
There is irregular combustion
When engine speed is measured, low idling and high idling speeds
are found to be high
Remove head cover and inspect directly
Remove feed pump and inspect directly
When check is made using delivery method, injection timing is found
to be incorrect
Injection pump measurement shows that injection amount is excessive
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
Gradually increased
Suddenly increased
Black
White
More than for other machines of same
model
Condition of fuel
consumption
Exhaust smoke color
Defective injection pump plunger Defecti
ve nozzle ho
lder spray
Defecti
ve in
jection p
ump
(excessi
ve in
jection
)
Defective fuel injection timing External leakage from fuel piping, fuel filter Leakage of fuel inside head cover Defective oil seal inside feed pump (piston) Defective adjustment
of fue
l control linkage
Causes
S-10 Fuel consumption is excessive
General causes why fuel consumption is excessive
• Leakage of fuel
• Improper condition of fuel injection
• Excessive injection of fuel
S-10
(1)