Komatsu GD555-5 Operation & Maintenance Manual page 243

TROUBLESHOOTING
Problem
Engine does not start when starting
motor is turned
Exhaust gas is white or blue
Exhaust gas sometimes turns black
Combustion noise occasionally
makes breathing sound
Abnormal noise generated (fuel
system or mechanical system)
Engine does not stop
3 - 190
Main causes
Lack of fuel
Air in fuel system
Defective fuel supply pump or
nozzle
Starting motor cranks engine
sluggishly
Engine preheating pilot ramp does
not light up
Defective compression
Defective valve clearance
Clogged fuel filter
Battery disconnect switch is OFF
Burnout of the fuse in the engine
controller circuit
Too much oil in oil pan
Improper fuel
Clogged air cleaner element
Defective injector
Defective compression
Defective turbocharger
Engine water temperature too low
Defective nozzle
Defective fuel injection pump
Air in fuel line
Clogged fuel filter
Low-grade fuel being used
Overheating
Damage inside muffler
Excessive valve clearance
Air in fuel line
Defective timing
Defective nozzle
Abnormality in controller power
source system
OPERATION
Remedy
Add fuel. For details, see
CHECK BEFORE STARTING
( Repair place where air is
sucked in)
( Replace pump or nozzle)
See ELECTRICAL SYSTEM
See ELECTRICAL SYSTEM
( Adjust clearance)
Replace filter
Turn switch ON
( Check, repair wiring)
Reduce oil to specified level
For details, see CHECK
BEFORE STARTING
Change to specified fuel
Clean or replace. For details,
see WHEN REQUIRED
( Replace injector)
( See "Defective compression"
above)
( Wash or replace turbocharger)
( Check, replace thermostat)
( Replace nozzle)
( Replace pump)
( Repair location of air entry)
Replace fuel filter
Change to specified fuel
See "Engine water
temperature gauge is in red
range top"
Replace muffler
( Adjust clearance)
Bleed air
( Check, adjust)
( Repair, replace)
( Check, repair wiring)