Komatsu WA480-8, Operation & Maintenance Manual

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TURBOCHARGER PROTECTION FUNCTION
The turbo protect function protects the turbocharger by keeping the engine speed at approximately 1000 rpm or
less immediately after the engine is started.
When the turbo protect function and automatic warm-up function operate at the same time, the turbo protect
function is given priority.
• While the turbo protect function is operating, increase of the engine speed is restricted even if the accelera-
tor pedal is depressed.
• When the turbo protect function is canceled, the engine speed becomes the speed according to the de-
pressed level of the accelerator pedal.
• The relationship between the actuating time of the turbo protect function and the temperature of the engine
coolant is as shown in the table.
Coolant temperature
( °C)
Turbo protect time (sec.)
Min. 10 0
10 to -30 Variable between 0 and 20
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:
1100 rpm) is performed automatically and stopped when the
engine coolant temperature increases to 60 °C or higher. (En-
gine speed 825 rpm)
(X): Engine speed ( rpm)
(Y): Coolant temperature ( °C)
METHOD FOR OPERATIONS AND CHECKS AFTER STARTING ENGINE
k k
WARNING
• 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.
OPERATION MACHINE OPERATIONS AND CONTROLS
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