Toro Groundsmaster 360 Service Manual page 78

2 Wheel Steering (continued)
4 Wheel Steering
Right Turn
Left Turn
Hydraulic System: Hydraulic Flow Diagrams
is recommended for transporting the machine. The switch indicator light will be
illuminated when the machine is in the 2 wheel steering operation.
In this switch position, the steering control manifold solenoid valve is not
energized. The flow from the steering control valve in either steering direction is
directed only to the front steering cylinder. The rear steering cylinder remains in
the centered, straight forward position.
When the rear of the steering selector switch is pressed with the wheels directed
straight forward, the 4 wheel steering will be active. The switch indicator light will
not be illuminated when the 4 wheel steering is active.
In this switch position, the steering control manifold solenoid valve is energized.
The flow from the steering control valve in either steering direction is directed to
both the front and rear steering cylinders.
When a right turn is made with the engine running, the turning of the steering
wheel positions the steering control spool valve so that the gear pump flow is
directed through the bottom of the spool. The flow entering the steering control
valve at the P port goes through the spool, is routed through rotary meter and out
the control valve R port. This flow moves to the steer mode selector valve and
then to the rear steering cylinder to retract the cylinder and turn the rear wheels
in the direction for a right turn. The hydraulic fluid displaced from the retracting
rear cylinder is directed to the front steering cylinder to retract that cylinder and
turn the front wheels in the direction for a right turn. The rotary meter ensures
that the fluid flow to the steering cylinders is proportional to the amount of turning
on the steering wheel. The fluid leaving the front steering cylinder flows back
through the steer mode selector valve, steering control spool valve, and then
out of the steering control valve through the T port and is routed to the oil cooler
and transmission case.
The steering control valve returns to the N
completed.
When a left turn is made with the engine running, the turning of the steering
wheel positions the steering control spool valve so that the gear pump flow is
directed through the top of the spool. The flow entering the steering control valve
at the P port goes through the spool, is routed through rotary meter and out the
control valve L port. This flow moves to the steer mode selector valve and then
to the front steering cylinder to extend the cylinder and turn the front wheels in
the direction for a left turn. The hydraulic fluid displaced from the extending front
cylinder is directed to the rear steering cylinder to extend that cylinder and turn
the rear wheels in the direction for a left turn. The rotary meter ensures that the
fluid flow to the steering cylinders is proportional to the amount of turning on the
steering wheel. The fluid leaving the rear steering cylinder flows back through
the steering control spool valve and then out of the steering control valve through
the T port and is routed to the oil cooler and transmission case.
The steering control valve returns to the neutral position when turning is
completed.
EUTRAL
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position when turning is
Groundsmaster 360
16225SL Rev C