Komatsu PW118MR-11 Operation & Maintenance Manual page 326

TROUBLES AND ACTIONS
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.
3-254
Main causes
Lowered coolant level, leakage of
coolant
Loose fan belt
Dirt or scale accumulated in cooling
system
Clogged radiator fins or damaged fin Clean or repair, See MAINTENANCE
Defective thermostat
Loose radiator filler cap (in high alti-
tude 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 Clean or repair, See MAINTENANCE
Defective thermostat
Loose radiator filler cap (in high alti-
tude operation)
Defective monitor
Lack of fuel
Air in fuel system
Defective fuel injection pump or de-
fective nozzle
Starting motor cranks engine slug-
gishly.
Preheating pilot lamp does not light
up.
Defective compression
(Incorrect valve clearance)
Excessive oil in oil pan
Incorrect fuel
Clogged air cleaner element
Defective nozzle
Defective compression
Defective turbocharger
WENAM00130
Remedy
Check, add coolant, or repair. See
CHECKS BEFORE STARTING.
Check fan belt tension, replace. (*)
Change coolant, flush inside of cool-
ing system. See WHEN REQUIRED.
EVERY 500 HOURS .
Replace thermostat (*)
Tighten the cap or replace packing.
Replace monitor (*)
Check, add coolant, or repair. See
CHECKS BEFORE STARTING.
Check fan belt tension, replace (*)
Change coolant, flush inside of cool-
ing system. See Maintenance when
required.
EVERY 500 HOURS .
Replace thermostat (*)
Tighten the cap or replace packing.
Replace monitor (*)
Top-up fuel. See CHECKS BEFORE
STARTING.
Repair the point where air is sucked
in. See EVERY 500 HOURS MAIN-
TENANCE.
Change pump or nozzle (*)
See PHENOMENA AND ACTIONS
FOR ELECTRICAL SYSTEM.
See PHENOMENA AND ACTIONS
FOR ELECTRICAL SYSTEM.
Adjust valve clearance (*).
Add oil to the specified level. See
CHECKS BEFORE STARTING.
Replace with specified fuel.
Clean or repair. See WHEN RE-
QUIRED.
Replace nozzle (*)
See the above section on defective
compression. (*)
Clean or replace turbocharger. (*)
OPERATION