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9803/
3280
Issue
1
Steer Unit Operation
- 4 Wheel Steer Machines
4 Wheel Steer Mode
- Right Turn, Unassisted
The illustration shows the circuit operation with the
engine stopped. Turning the steering wheel rotates
the inner spool
A
until the cross pin engages with
and rotates outer sleeve
B
, metering oil to the
stator
D
, and pumping it out to power track rod
rams
40
and
41
under manual pressure only.
As there is no supply from the pump, oil from one
side of the power track rod rams, supplemented by
exhaust oil if necessary, is used to feed the other
side via non-return valve
F
.
Component Key:
A
Inner Spool
B
Outer Spool
D
Stator
F
Non-Return Valve
X
Steer Mode Control Valve
40
Front Power Track Rod Ram
41
Rear Power Track Rod Ram
4 -
9
4 -
9
Cir
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