Komatsu H75051 Operation & Maintenance Manual page 307

OPERATION
Problem
Oil pressure is low.
Movement of cylinder is irregular.
Lock of exterior parts
The grille lock is too stiff to open.
PHENOMENA AND ACTIONS FOR ENGINE RELATED PARTS
• For the remedies indicated with (*) in the remedy column, always contact your Komatsu distributor.
• In cases of problems or causes which are not listed below, ask your Komatsu distributor for repairs.
Problem
Engine oil pressure caution lamp
lights up.
Steam spurts out from top of radiator
(pressure valve).
Indicator of engine coolant tempera-
ture gauge is in red range
Engine coolant temperature caution
lamp lights up.
Main causes
Pump sucks air due to the lack of oil
in the hydraulic tank
Lack of oil in the hydraulic tank
Sand is inside the sliding portion of
the lock.
Main causes
Lowered oil level in engine oil pan
(sucking in air)
Improper oil is used. (Viscosity is im-
proper.)
Clogged oil filter cartridge
Oil leakage due to improper connec-
tion or breakage of oil pipe or pipe
joint
Defective engine oil pressure sensor
Defective monitor
Lowered coolant level, leakage of
coolant
Defective fan pump or motor
Accumulation of dirt or scale in cool-
ing system
Clogged radiator fins or damaged fin
Defective thermostat
Defective sealing of thermostat
Loose radiator filler cap
(In high altitude operation)
Defective coolant temperature gauge
Defective coolant level sensor
Defective monitor
TROUBLES AND ACTIONS
Remedy
Add oil by referring to EVERY 100
HOURS MAINTENANCE. And then,
bleed air by referring to EVERY 2000
HOURS MAINTENANCE.
Add oil to specified level by referring
to EVERY 100 HOURS MAINTE-
NANCE.
Clean it with air blow or water.
(Do not use oil or grease. They may
attract the sand.)
Remedy
Set oil to specified level. See
CHECKS BEFORE STARTING.
Replace oil. See USE OF FUEL,
METHOD FOR USING FUEL, COOL-
ANT AND LUBRICANTS ACCORD-
ING TO AMBIENT TEMPERATURE.
Replace cartridge. See EVERY 500
HOURS MAINTENANCE.
Check, repair. (*)
Replace sensor. (*)
Replace monitor. (*)
Check, add coolant, or repair. See
WHEN REQUIRED.
Check, repair. (*)
Check, add coolant, or repair. See
WHEN REQUIRED.
Clean or repair them. See WHEN
REQUIRED.
Replace thermostat. (*)
Replace thermostat seal. (*)
Tighten cap or replace packing.
Replace coolant temperature gauge.
(*)
Replace sensor.
Replace. (*)
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