Komatsu PW118MR-11, Operation & Maintenance Manual

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