Komatsu 75001, Shop Manual

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SEN03849-00
WA250, 250PZ-6 40-500
15
500 Troubleshooting of hydraulic and mechanical system (H-mode)
H-8 Steering wheel shakes or jerks
H-8 Steering wheel shakes or jerks
1
H-9 Machine deviates naturally to one side when traveling
1
Causes: Defective steering
q
Defective operation of safety valve
q
Oil leakage inside steering cylinder
q
Variation in tire inflation pressure
Checks before troubleshooting
q
Is the hydraulic oil level correct? Is the type of oil correct?
q
Is there any play in the center hinge pin bearing or steering cylinder pin or
bushing?
q
Is there any variation in the tire inflation pressure?
q
Is the steering wheel play correct?
Check for abnormalities
q
Operate at a safe place and check how the steering wheel shakes and under
what conditions.
a In cases where the steering wheel is heavy but does not shake, go to “H-7 The
steering wheel is heavy”.
Cause
Valves Cylinder Valves
a b c d
De
fec
t i
n
si
de O
rbi
t-
ro
ll
D
e
fe
ct
iv
e
2
-w
a
y
r
e
st
ri
ct
o
r v
a
lv
e
De
fe
ct
i
n
si
de st
e
e
ri
ng cyl
inder
(
insi
de sur
fa
c
e of
cyl
inder
,
pi
st
on seal
,
n
u
t,
b
o
lt
)
D
e
fe
ct
iv
e
c
u
sh
io
n
va
lv
e
No.
Remedy
Diagnosis
E
X X
E
X
E
X
1 Chassis shakes when traveling on rough road surface
Q Q Q
2 Shakes when steering is suddenly turned during operation or travel
Q Q Q
3 Chassis shakes when accelerating during travel operations
Q Q Q
4 Chassis shakes when engine is started
Q
5 Excessive shock when steering wheel is turned back
Q