Komatsu D31EX-21, Operation & Maintenance Manual, Page: 132 / 256

OPERATION
OPERATION
3-80
3. Insert the key into starting switch (2) and turn it to the
HEAT position. Engine preheating pilot lamp (3) will light
up.
Keep it at the HEAT position for the specified preheating
time.
The preheating times are as shown below.
If the preheating time is too long or too short, the engine will not start easily. Observe the correct preheating time.
4. When the preheating is completed, turn the key in starting
switch (2) to the START position to start the engine.
5. When the engine starts, release the key in starting switch
(2). The key will return automatically to the ON position.
6. When the engine rotation stabilizes, return to the low idle position of fuel control lever (1) and then carry out
the warming-up operation.
Ambient temperature Preheat time
Abave 0°C -
0°C to -10°C Approx. 20 seconds
-10°C to -20°C Approx. 30 seconds