Komatsu D475A-5E0 Operation & Maintenance Manual page 241

TROUBLESHOOTING
ENGINE
( ): Always contact your Komatsu distributor when dealing with these items.
In cases of problems or causes which are not listed below, ask your Komatsu distributor for repairs.
Problem
Engine oil pressure monitor
flashes when engine speed is
raised after completion of
warm-up
Steam is emitted from top part
of radiator (pressure valve)
Engine coolant temperature
monitor remains lit
Engine does not start when
starting motor is turned
Exhaust gas is white or blue
Exhaust gas occasionally turns
black
Combustion noise occasionally
makes breathing sound
Abnormal noise generated
(combustion or mechanical)
3 - 188
Main causes
Engine oil pan oil level is low
(sucking in air)
Clogged oil filter cartridge
Defective tightening of oil pipe
joint, oil leakage from damaged
part
Defective monitor panel
Coolant level low, leakage
Fan rotation speed is low
Dirt or scale accumulated in
cooling system
Clogged radiator fin or damaged
fin
Defective thermostat
Loose radiator filler cap (high
altitude operation)
Defective monitor panel
Lack of fuel
Air in fuel system
Defective fuel injection pump or
nozzle
Starting motor cranks engine
sluggishly
Defective valve clearance
Too much oil in oil pan
Improper fuel
Clogged air cleaner element
Defective nozzle
Defective compression
Defective turbocharger
Defective compression
Low grade fuel being used
Overheating
Damage inside muffler
Excessive valve clearance
Remedy
Add oil to specified level, see
CHECK BEFORE STARTING
Replace cartridge, see EVERY 500
HOURS SERVICE
( Check, repair)
( Replace)
Add coolant, repair, see CHECK
BEFORE STARTING
Check and repair hydraulic circuit of
fan motor
Change coolant, clean inside of
cooling system, see WHEN
REQUIRED
Clean or repair, see WHEN
REQUIRED
( Replace thermostat)
Tighten cap or replace packing
( Replace)
Add fuel, see CHECK BEFORE
STARTING
Repair place where air is sucked in
( Replace pump or nozzle)
See ELECTRICAL SYSTEM
( Adjust valve clearance)
Add oil to specified level, see
CHECK BEFORE STARTING
Change to specified fuel
Clean or replace, see WHEN
REQUIRED
( Replace nozzle)
( Adjust valve clearance)
( Clean or replace,turbocharger)
( Replace nozzle)
Change to specified fuel
See item "Engine coolant
temperature monitor remains lit"
( Replace muffler)
( Adjust valve clearance)
OPERATION