Komatsu PC130-7, Shop Manual

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PC130-7
20-609
TROUBLESHOOTING
Check items
Questions
Troubleshooting
Causes
Confirm recent repair history
Degree of use of machine
Replace Replace Replace Replace Replace Replace Replace Replace Replace Replace
Remedy
Exhaust smoke suddenly stops coming out (when starting again)
Fuel tank is found to be empty
There is leakage from fuel piping
Mud is stuck to fuel tank cap
Rust and water are found when fuel tank is drained
Inspect injection pump directly
When control rack is pushed, it is found to be heavy, or does
not return
Inspect feed pump directly
When fuel filter, strainer are inspected directly, they are found to be
clogged
When feed pump strainer is inspected directly, it is found
to be clogged
When fuel cap is inspected directly, it is found to be clogged
Cannot be moved by hand even when linkage of fuel cut
solenoid is disconnected
When starting switch is turned ON, linkage is not actuated
When fuel filter is drained, fuel does not come out
When engine is cranked with starting motor,
1) No fuel comes out even when fuel filter air bleed plug is
loosened
2) No fuel spurts out even when injection pump piping sleeve nut is
loosened
Broken injection pump drive shaft, key Defective injection pump (rack, plunger seized) Seized, broken feed pump piston Clogged fuel filter, strainer Clogged feed pump strainer Insufficient fuel in tank Clogged, leaking fuel piping Clogged air breather hole in fuel tank Defective fuel cut solenoid Improper fuel used
Replacement of filters has not been carried out according to Operation
Manual
Operated for long period
(2) Engine turns but no exhaust smoke comes out
(Fuel is not being injected)
General causes why engine turns but no exhaust smoke
comes out
• Supply of fuel impossible
• Supply of fuel is extremely small
• Improper selection of fuel (particularly in winter)
a
Standards for use of fuel
KIND OF
FLUID
AMBIENT TEMPRATURE
-4 14 32 50 68°F
-20 -10 0 10 20°C
Diesel fuel
ASTM D975 No.2
ASTM D975 No.1
S-2
(1)