Komatsu PC308USLC-3E0 Operation & Maintenance Manual page 147

OPERATION
Engine Warm Up
NOTICE
Do not accelerate the engine suddenly until the warm-up operation has
been completed.
Do not run the engine at low idling or high idling under no load for more
than 20 minutes. This will have an adverse effect on the environment,
and will also have an adverse effect on the internal structure of the
engine. If it is necessary to run the engine at idling for more than 20
minutes, apply a load from time to time or run at a mid-range speed.
After the engine starts, do not start operating the machine immediately. First, carry out the following operations and
checks.
1. This machine is equipped with an automatic engine warm-up system, so if the engine water temperature is
below 30 °C after the engine is started, the engine warm-up operation starts automatically. When the engine
automatic warm-up operation starts, the engine speed is maintained at a speed higher than the normal low idling
speed.
If the engine water temperature goes above 30 °C or if the warm-up operation has been continued for more than
10 minutes, the automatic warm-up operation is cancelled and the engine speed drops to the normal low idling
speed.
2. Check that engine water temperature monitor (1) displays
green.
If it displays white, use the procedure in Step 3 to carry out
additional warm up of the engine until the monitor displays
green.
3. Turn fuel control dial (2) to a point midway between low idling
(MIN) and full speed (MAX), run the engine at a mid-range
speed, and run under no load until engine water temperature
monitor (1) displays green.
If the engine water temperature monitor displays green, the engine warm-up operation is completed.
After checking that the engine water temperature monitor displays green, carry out the warming-up operation for the
hydraulic equipment.
MACHINE OPERATIONS AND CONTROLS
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