H-7 The Steering Wheel Is Heavy - Komatsu WA250-6 Shop Manual

SEN03849-00

H-7 The steering wheel is heavy

Ask the operator about the following:
Did the problem suddenly start?
q
o
Breakage of steering related equipment
Was there previously any symptom, such as heavy steering?
q
o Internal wear of steering related equipment, defective
seal
Inspection before diagnosis
Are the oil level in the hydraulic tank and the oil type appropri-
q
ate?
Is there any abnormality in
q
Is the any external oil leak found around the hydraulic piping,
q
valve and cylinder?
Is there any gouging of center hinge pin bearing and steering
q
cylinder pin, bushing?
Is the tire inflation pressure correct?
q
Check for abnormalities
Measure operating effort of steering wheel and time taken to
q
turn steering, and check standard judgement value table to
see if there is any abnormality.
No.
Diagnosis
1 Steering wheel is heavy when turned in both directions (left and right)
2 Steering wheel is heavy when turned in one direction (left and right)
Steering wheel is heavy particularly when engine is running at low
3
speed
4 Lift arm lifting speed is slow when engine is running at full speed
5 Steering wheel is heavy and there is jerking
6 Hydraulic oil overheats
7 Oil pressure of steering circuit is low or there is no pressure
8 Pressure rises in return piping of steering cylinder
14
40-500
500 Troubleshooting of hydraulic and mechanical system (H-mode)
, steering column linkage?
Orbit-roll
H-7 The steering wheel is heavy
Hydraulic
Valve
pump
a b
E E
Remedy
X X
Q Q
Q
Q Q
Q
Q
Q
1
Cause
Others
c d e f
E E E E E
X X X X X
A C C
Q Q Q
Q
Q Q
Q
Q
Q Q Q
Q
Q
WA250, 250PZ-6