H-4 Engine Stalls When Traveling Or Engine Speed Drops Excessively - Komatsu WA250-6 Shop Manual

500 Troubleshooting of hydraulic and mechanical system (H-mode)

H-4 Engine stalls when traveling or engine speed drops excessively

H-4 Engine stalls when traveling or engine speed drops excessively
Ask the operator about the following:
Was there any problem before?
q
o
Dirt in HST pump, motor related equipment
Inspection before diagnosis
Is the any external oil leak found around the hydraulic piping, pump and
q
motor?
No.
Diagnosis
1 Engine stalls when traveling or engine speed drops excessively
2 Machine moves when the directional lever is at F or R and engine is at Lo
WA250, 250PZ-6
SEN03849-00
Cause
HST HST
pump motor 2
a b
E E
Remedy
X X
Q Q
Q
40-500
1
Others
c
E
X
Q
11