Komatsu PC130-7, Shop Manual

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PC130-7
20-611
TROUBLESHOOTING
Confirm recent repair history
Operated for long period
Check items
Questions
Degree of use of machine
Troubleshooting
Clean Clean Clean Correct Replace Replace Replace Adjust Clean Correct Replace
Remedy
Noise of interference is heard from around turbocharger
Non-specified fuel is being used
Engine oil must be added more frequently
Rust and water are found when fuel tank is drained
Dust indicator lamp is red
Replacement of filters has not been carried out according to
Operation Manual
Color of exhaust gas
Blue under light load
Black
Clanging sound is heard from around cylinder head
Mud is stuck to fuel tank cap
There is hunting from engine (rotation is irregular)
When exhaust manifold is touched immediately after starting
engine, temperature of some cylinders is low
When fuel filter, strainer are inspected directly, they are
found to be clogged
When air cleaner element is inspected directly, it is found to
be clogged
Blow-by gas is excessive
There is leakage from fuel piping
High idling speed under no load is normal, but speed
suddenly drops when load is applied
When feed pump is operated, operation is too light or too heavy
When fuel tank cap is inspected directly, it is found to be clogged
When valve clearance is checked directly, it is found to be
outside standard value
When turbocharger is rotated by hand, it is found to be heavy
When compression pressure is measured, it is found to be low
When control rack is pushed, it is found to be heavy, or does not return
Speed does not change when operation of certain cylinders
is stopped
When feed pump strainer is inspected directly, it is found to be
clogged
Engine pick-up suddenly became poor
Worn piston rin
g, cy
linder
liner
Sei
zed injection p
ump plunger
Clogged fuel fi
lter, strainer
Clogged fee
d pump strainer
Cl
ogged
air c
leaner e
lement
Seized turbochar
ger, interference
Clogged, leak
ing fuel pipin
g
Defective contact of valve and
valve seat
Clogged injection nozzle,
defective spray
Clogged air breather ho
le in fuel tank cap
Improper valve clearance
Causes
S-3 Engine does not pick-up smoothly
(Follow-up is poor)
General causes why engine does not pick up smoothly
•
Insufficient intake of air
• Insufficient supply of fuel
• Improper condition of fuel injction
• Improper fuel used
S-3
(1)