Method For Operations And Checks After Starting Engine - Komatsu H75051 Operation & Maintenance Manual

MACHINE OPERATIONS AND CONTROLS
METHOD FOR OPERATING AUTOMATIC WARM-UP SYSTEM
When starting the engine, if the engine coolant temperature is
20 °C or less, the warming-up operation (engine speed:
1000 rpm) is performed automatically and stopped when the
engine coolant temperature increases to 30 °C or higher. (En-
gine speed 825 rpm)
(X): Engine speed ( rpm)
(Y): Coolant temperature ( °C)

METHOD FOR OPERATIONS AND CHECKS AFTER STARTING ENGINE

• If there has been any emergency stop, abnormal actuation, or other trouble, turn the starting switch
key to OFF position.
• If you cannot stop the engine by turning the starting switch to OFF position, use the engine shut-
down secondary switch to stop the engine.
• If the work equipment is operated without sufficient warming-up operation of the machine, response
of the work equipment to movement of the control lever will be slow, and the work equipment may
not respond as the operator desires. Be sure to perform the warm-up operation.
Particularly in a cold weather, be sure the warm-up operation is completed.
• If the machine is operated without sufficient warming-up operation, sensors may break because of
frozen DEF tank.
• Keep away from the exhaust pipe while the engine is running and immediately after stopping the
engine.
Keep combustible materials away from the exhaust pipe outlet.
METHOD FOR CHECKING STARTING CONDITION AND UNUSUAL NOISE OF
ENGINE
• When starting the engine, check that the engine causes no abnormal noise and that it starts up easily and
smoothly.
• Check that there is no abnormal noise when the engine is idling or when the engine speed rises slightly.
When there is an abnormal noise at the engine startup and if that condition continues, the engine may be dam-
aged. In that case, ask your Komatsu distributor to check the engine as soon as possible.
METHOD FOR CHECKING LOW-SPEED RUN AND ACCELERATION OF ENGINE
When stopping the machine during the normal traveling operation, check that the engine does not hunt or stop
suddenly.
When the accelerator pedal is depressed, check that the engine speed rises smoothly.
• Perform these checks in a safe place, watching out for danger in the surroundings.
• When the engine performs very badly at low idle and in the acceleration and if that condition continues, it
may damage the engine or confuse the operator's sense of driving or lower the braking efficiency, and as a
result lead to an unexpected accident. In that case, ask your Komatsu distributor to check the engine as
soon as possible.
REMARK
• The smell of the exhaust gas is different from that of the conventional diesel engine because of the exhaust
gas aftertreatment devices.
• White smoke may be discharged for a short time immediately after the engine is started or during the after-
treatment devices regeneration in the cold season, but this is not a failure.
3-178
k k
WARNING
OPERATION