Komatsu PC450-8 Operation & Maintenance Manual page 264

TROUBLES AND ACTIONS
Engine
q
( ): Always contact your Komatsu distributor when dealing with these items.
q
In cases of problems or causes which are not listed below, contact your Komatsu distributor for repairs.
Problem
Engine oil pressure monitor lights up
Steam spurts out from top of radiator
(pressure valve)
Radiator coolant level monitor lights
up
Engine does not start when starting
motor is turned
Exhaust gas is white or blue
Exhaust gas occasionally turns
black
Combustion noise occasionally
make breathing sound
3-198
Main causes
•Engine oil pan oil level is low (suck-
ing in air)
•Clogged oil filter cartridge
•Defective tightening of oil pipe, pipe
joint, oil leakage from damaged
point
•Defective engine oil pressure sen-
sor
•Defective monitor
•Coolant level low, leakage of water
•Loose fan belt
•Dirt or scale accumulated in cooling
system
•Clogged radiator fins or damaged
fins
•Defective thermostat
•Loose radiator filler cap (high-alti-
tude operations)
•Defective water level sensor
•Defective monitor
•Lack of fuel
•Air in fuel system
•Defective fuel injection pump or
defective nozzle
•Starting motor cranks engine slug-
gishly
•Engine pre-heating monitor does
not light up
•Defective compression
(Defective valve clearance)
•Too much oil in oil pan
•Improper fuel
•Clogged air cleaner element
•Defective nozzle
•Defective compression
•Defective turbocharger
•Defective nozzle
OPERATION
Remedy
•Add oil to specified level, see
CHECK BEFORE STARTING
•Replace cartridge, see EVERY
500 HOURS SERVICE
(•Check, repair)
(•Replace sensor)
(•Replace monitor)
•Check, add coolant, repair, see
CHECK BEFORE STARTING
•Check fan belt tension, adjust,
replace
•Change coolant, flush inside of
cooling system, see WHEN
REQUIRED
•Clean or repair, see EVERY 500
HOURS SERVICE
(•Replace thermostat)
•Tighten cap or replace packing
(•Replace sensor)
(•Replace monitor)
•Add fuel, see CHECK BEFORE
STARTING
•Repair place where air is sucked
in, see EVERY 500 HOURS
SERVICE
(•Replace pump or nozzle)
•See ELECTRICAL SYSTEM
•See ELECTRICAL SYSTEM
(•Adjust valve clearance)
•Set oil to specified level, see
CHECK BEFORE STARTING
•Change to specified fuel
•Clean or replace, see WHEN
REQUIRED
(•Replace nozzle)
(•See defective compression
above)
(•Clean or replace turbocharger)
(•Replace nozzle)
3