Komatsu 37BF50111, Operation & Maintenance Manual

Page: 151 / 244

TROUBLESHOOTING
149
3.15.4.3 ENGINE
TROUBLE CAUSE REMEDY
Oil pressure warning light remains on
even with engine at high speed
• Oil level in oil pan too low.
• Oil filter clogged.
• Oil unsuitable for the season. • Top up..
• Change filter.
• Change.
Steam comes out of radiator breather pi-
pe:
Engine coolant temperature indicator re-
aches overheating red range:
• Fluid level low, fluid leakages.
• Fan belt slackened.
• Mud or limestone accumulated in
cooling system.
• Radiator fins damaged or closed.
• Faulty thermostat.
• Radiator cap loose or broken.
Working at considerable altitude.
• Top up, repair.
• Check belt tension.
• Change fluid and clean cooling
system.
• Repair or clean.
(•) Change.
• Tighten cap or change unit.
Engine coolant temperature indicator
always at the end of right scale • Faulty instrument. (•) Change.
Engine coolant temperature indicator
always at the end of left scale:
• Faulty thermostat.
• Faulty instrument. (•) Change.
(•) Change.
Engine does not start with starter run-
ning:
• No fuel.
• Air in fuel system.
• Compression defect (valves with
wrong clearance).
• Refuel.
• Bleed system.
(•) Adjust valve clearance.
Exhaust gases white or light blue:
• Too much oil in oil pan.
• Unsuitable fuel. • Correct oil level.
• Change with fuel in compliance with
standards.
Exhaust gases occasionally tend to be
black:
• Air cleaner clogged.
• Faulty injectors.
• Faulty compression. • Clean or change.
(•) Change.
(•) Adjust valve clearance.
Combustion noise occasionally resem-
bles a blow: • Faulty injectors. (•) Change.
Abnormal noises (during combustion or
in mechanical parts):
• Fuel with low cetane rating.
• Overheating.
• Exhaust silencer inside damaged.
• Excessive valve clearance.
• Change with fuel in compliance with
standards.
• See «defects of temperature indica-
tor».
(•) Change.
(•) Adjust valve clearance.