Komatsu PC138USLC Operation & Maintenance Manual page 192

OPERATION OPERATION
8. Check that battery charge monitor (4), engine oil pressure
monitor (5), and engine oil level monitor (6) are off.
Turbo protect function
The turbo protect function is a function to protect the turbocharger by keeping the engine speed at less than 1100
rpm immediately after the engine is started.
When the turbo protect function is actuated, the engine speed is held at less than 1100 rpm, regardless of the
position of the fuel control dial.
When the turbo protect function is actuated, the engine speed is held at less than 1100 rpm, even if the fuel control
dial is operated.
When the turbo protect function is canceled, the engine speed is set to the speed for the position of the fuel control
dial.
The relationship between the length of time of actuating the
turbo protect function and the temperature of the engine coolant
is as shown in the table.
MACHINE OPERATIONS AND CONTROLS MACHINE OPERATIONS AND CONTROLS
Coolant Turbo protect
temperature
Above 10 ° C (50 ° F)
10 to -30 ° C
Change 0 to 20
(50 to -22 ° F)
below -30 ° C (22 ° F)
time (sec.)
0
20
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