SkyTrak 6036 Service Manual - Manual (Page 312)

Hydraulic System
8.96 Model 6036 Legacy
8.12.7 Steer Select Valve
The vehicle can be used in the front-wheel, four-wheel or
crab steering mode. The steer select valve (Fig. 8-59, 1)
controls the direction of hydraulic fluid flow to the steering
cylinders mounted on each axle. The steer select valve
(1) is attached to a manifold (2) mounted on a mounting
plate inside the frame near the fuel tank (3).
Figure 8-59 Steer Select Valve Location
The steer select valve (Fig. 8-60, 1) contains two solenoids
(2) that direct the flow of hydraulic fluid according to
steering input. The valve is a direct dual-solenoid operated,
spool-type main control valve.
The valve consists of a housing (Fig. 8-60, 1), two solenoids
(2), a control spool (3) and two return springs (4). In the
de-energized state, the spool (3) is held by the return
springs (4) in the center position.
The spool is shifted via the action of the two wet-pin type
solenoids (Fig. 8 -60, 2). The force of an acting solenoid
pushes against the push pin (5) on the end of the spool
(3). The spool is shifted from its normal position to the end
position for selected flow.
When the solenoid is de-energized, the control spool
(Fig. 8 -60, 3) is returned to its normal condition by the
centering springs (4).
Figure 8- 60 Steer Select Valve and Manifold
Verify the correct operation of the steer select valve solenoids
before considering replacement of the valve. Refer to
Section 9.7, “Electrical System Troubleshooting” and
Section 9.15.9, “Steer Select Valve.” The housing
(Fig. 8-60, 1) of the steer select valve is not serviceable
and must be replaced if defective.
a. Steer Select Manifold and Valve Removal
1. Park the vehicle on a firm, level surface, fully retract
the boom, raise the boom, place the travel select
lever in (N) NEUTRAL, place the neutral lock lever in
the (N) NEUTRAL LOCK position, engage the park
brake switch and shut the engine OFF.
2. Place an Accident Prevention Tag on both the
ignition key switch and the steering wheel, stating
that the vehicle should not be operated. Refer to
Section 1.5, “Accident Prevention Tag Usage.”
3. Temporarily block up or support the raised boom.
MA8320
1
2
3
Front
WARNING:
DO NOT get under a raised
boom unless the boom is blocked up. Always
block the boom before doing any servicing that
requires the boom to be up. Unexpected lowering
of the boom may cause death or serious injury.
MA8370
2
1
2
3
5 1
5
4 4