Komatsu Galeo PC138US-8 Shop Manual page 274

SEN02553-01
Turbocharger protection function
a See "Engine automatic warm-up function" for system circuit diagram.
When the engine is started at low temperatures and the engine speed is increased sharply, the turbo-
q
charger may be seized. Controlling the engine speed prevents this problem.
Duration of engine speed control depends on the coolant temperature.
q
Engine oil pressure: Max. 50 kPa {0.51 kg/cm
A: Start engine
B: Duration of turbocharger protection (approx. 0
– 20 sec)
C: Modulating time (approx. 1.5 sec)
D: 500 rpm
E: 1,100 rpm
F: 2,300 rpm (*1)
*1. Working mode: Mode P
Fuel control dial: Full rotation (MAX) position
Travel lever operated
16
Operational conditions
}
2
10 Structure, function and maintenance standard
o
Operating
Turbocharger protection
(See the following figure)
PC138US, USLC-8