Komatsu D375A-8, Operation & Maintenance Manual

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Problem Main causes Remedy
Engine coolant temperature caution
lamp lights up. Engine coolant is insufficient, coolant
leaks. Check, add coolant, repair by refer-
ring to CHECKS BEFORE START-
ING.
Fan speed is low. Check and repair fan motor hydraulic
circuit.
Dirt or scale accumulated in cooling
system Change coolant, flush inside of cool-
ing system by referring to WHEN RE-
QUIRED.
Clogged radiator fins or damaged fin Clean or repair by referring to WHEN
REQUIRED.
Thermostat has a trouble. Replace thermostat. (*)
Loose radiator filler cap (in high alti-
tude operation) Tighten the cap or replace packing.
Defective monitor Replace monitor. (*)
Starting motor operates but engine
does not start. Fuel is insufficient. Add fuel by referring to CHECKS BE-
FORE STARTING.
Air is mixed in fuel system. Repair the part where air is sucked in.
Defective fuel injection pump or de-
fective nozzle Replace pump or nozzle. (*)
Starting motor is incapable of crank-
ing engine smoothly. See “PHENOMENA AND ACTIONS
FOR ELECTRICAL SYSTEM”.
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.
Improper fuel is used. Replace with specified fuel.
Exhaust gas sometimes becomes
black. Clogged air cleaner element Clean or replace by referring to
WHEN REQUIRED.
Defective nozzle Replace nozzle. (*)
Compression is improper. See "Compression is improper"
above. (*)
Defective turbocharger Clean or replace turbocharger. (*)
Combustion sound sometimes fluctu-
ates. Defective nozzle Replace nozzle. (*)
Unusual noise is generated.
(Combustion or mechanical) Low grade fuel being used Replace with specified fuel.
Overheating See “Engine coolant temperature
caution lamp lights up” shown above.
Valve clearance is excessive. Adjust valve clearance. (*)
TROUBLES AND ACTIONS OPERATION
3-250