Komatsu PW98MR-10 Operation & Maintenance Manual page 303

OPERATION
Problem
Steam spurts out from top of radiator
(pressure valve).
Indicator of engine coolant tempera-
ture gauge is in red range.
Starting motor rotates but engine
does not start.
Exhaust gas color is white or bluish.
Exhaust gas turns black from time to
time.
Main causes
Lowered coolant level, leakage of
coolant
Loose fan belt
Dirt or scale accumulated in cooling
system
Clogged radiator fins or damaged fin
Defective thermostat
Loosened radiator filler cap (in high
altitude operation)
Defective monitor
Lowered coolant level, leakage of
coolant
Loose fan belt
Dirt or scale accumulated in cooling
system
Clogged radiator fins or damaged fin
Defective thermostat
Loosened radiator filler cap (in high
altitude operation)
Defective monitor
Lack of fuel
Air in fuel system
Defective fuel injection pump or de-
fective nozzle
Starting motor turns engine sluggish-
ly.
Preheating pilot lamp does not light
up.
Defective compression
(Defective valve clearance)
Excessive oil in oil pan
Improper fuel
Clogged air cleaner element
Defective nozzle
Defective compression
Defective turbocharger
WENAM00061
TROUBLES AND ACTIONS
Remedy
Check, add coolant, repair. See
CHECKS BEFORE STARTING.
Check fan belt tension, replace. (*)
Change coolant, flush inside of cool-
ing system. See WHEN REQUIRED.
Clean or repair. See EVERY 500
HOURS MAINTENANCE.
Replace thermostat. (*)
Tighten cap or replace packing.
Replace monitor. (*)
Check, add coolant, repair. See
CHECKS BEFORE STARTING.
Check fan belt tension, replace. (*)
Change coolant, flush inside of cool-
ing system. See WHEN REQUIRED.
Clean or repair. See EVERY 500
HOURS MAINTENANCE.
Replace thermostat. (*)
Tighten cap or replace packing.
Replace monitor. (*)
Add fuel. See CHECKS BEFORE
STARTING.
Repair place where air is sucked in.
See EVERY 500 HOURS MAINTE-
NANCE.
Replace pump or nozzle. (*)
See PHENOMENA AND ACTIONS
FOR ELECTRICAL SYSTEM.
See PHENOMENA AND ACTIONS
FOR ELECTRICAL SYSTEM.
Adjust valve clearance. (*)
Set oil to specified level. See
CHECKS BEFORE STARTING.
Replace with specified fuel.
Clean or replace. See WHEN RE-
QUIRED.
Replace nozzle. (*)
See the above section on defective
compression. (*)
Clean or replace turbocharger. (*)
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