SkyTrak 8042 Service Manual - Manual (Page 479)

Hydraulic System
8.64 Model 8042, 10042, 10054 Legacy Rev. 10/03
8.8.29 Steering Circuit Descriptions
Vehicle steering includes front-wheel steering, four-
wheel steering and crab steering.
a. Front-Wheel Steering
When the steer select switch (1) is in the front-
wheel steer (center) position (2), the front wheels
(3) will steer in the direction the steering wheel is
turned and the rear wheels (4) will remain fixed.
1. Front-Wheel Steering Left Turn
(refer to page 8.46)
In the front-wheel steering mode, when a left turn is
made, system pressure from the secondary function
manifold is applied through the intake side of the
metering section of the power steering unit.
A specific amount of hydraulic oil is exhausted from the
metering section and routed to the power steering control
valve, internal to the power steering unit, where it is
channeled to the left rod end of the front steering cylinder.
Oil from the right rod end of the front steering cylinder
flows through the steer select valve to the power steering
unit, then to the oil cooler and to the return filter in the
reservoir. Both solenoids in the steer select valve are
deenergized.
2. Front-Wheel Steering Right Turn
(refer to page 8.48)
When a right turn is made, the steering unit spool is
shifted so that system pressure from the secondary
function manifold is applied to the intake side of the
metering section of the power steering unit.
A specific amount of hydraulic oil is exhausted from the
metering section and routed to the power steering control
valve, internal to the power steering unit, where it is
channeled through the steer select valve to the right rod
end of the front steering cylinder. Both solenoids in the
steer select valve are de-energized.
Oil from the left rod end of the front steering cylinder flows
to the power steering control valve, then to the oil cooler
and to the return filter in the reservoir.
MA7010
1
2
3
4
1
MT3870