Komatsu D375A-8, Operation & Maintenance Manual

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METHOD FOR ENGINE WARM-UP OPERATION
NOTICE
• Do not perform the operations or operate the levers
sharply while the hydraulic oil is at low temperature.
Perform the warm-up operation until the hydraulic oil
temperature caution lamp is displayed in green. Per-
forming the warm-up operation properly will extend
the service life of the machine.
Do not suddenly accelerate the engine before the
warm-up operation is completed.
• Do not run the engine at low idle or high idle with no
load for more than 20 minutes. This will have an ad-
verse effect on the environment and also on the inter-
nal structure of the turbocharger and engine. If it is
necessary to run the engine at idle, apply a load from
time to time or run at a medium speed.
• If the engine oil pressure caution lamp on the machine
monitor (2) lights up and the buzzer sounds intermit-
tently, stop the engine and check it.
• This machine is equipped with an automatic engine warm-
up system, so if the engine coolant temperature is 30 °C or
lower after the engine is started, the engine warm-up oper-
ation starts automatically.
• When the engine automatic warm-up operation starts, the engine speed is maintained higher than the nor-
mal speed at low idle.
• If the engine coolant temperature goes 30 °C or higher or if the warm-up operation is continued for more
than 10 minutes, the automatic warm-up operation is canceled and the engine speed drops to the normal
speed at low idle.
Do not start operating the machine immediately after the engine starts. First, perform the following operations
and checks.
1.
Check that the engine coolant temperature gauge points
the correct temperature range (A) to (C).
2.
If it points the low temperature range (C) to (D), perform
the additional warm-up operation according to the step 3
until it points the correct temperature range (A) to (C).
3.
Turn the fuel control dial (1) to a position midway between
Low idle (MIN) and High idle (MAX).
4.
Run the engine at a medium speed, and then run it with no
load or with a light load until the engine coolant tempera-
ture gauge rises to point the correct temperature range (A)
to (C).
5.
Check for abnormal exhaust gas color, noise, or vibration.
If any problem is found, contact your Komatsu distributor.
If the engine coolant temperature gauge points the correct temperature range, the engine warm-up operation is
completed.
MACHINE OPERATIONS AND CONTROLS OPERATION
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