TM 5-3810-307-24-1-1
front steering gear. The mechanical input to the
valve to the appropriate ends of the front axle steer-
steering gear shifts the internal valving within the
ing cylinders.
gear which routes hydraulic flow from the steering
gear through the double selector valve to the
REAR AXLE STEERING FROM THE SUPER-
applicable ends of the front steer cylinders as
STRUCTURE.
determined by the positioning of the steering wheel
in the cab.
For rear axle steering from the superstructure the
steering mode control handle must be pulled out.
REAR AXLE STEERING FROM THE CARRIER.
Hydraulic flow for steering is provided by the steering
The steering mode selector must be in the CARRIER
pump. Flow from the pump is routed through the
position (handle pushed in) to enable steering
single selector valve, through the swivel to the steer-
control.
ing control valve. The steering control valve routes
flow through the steer selector valve, through the
Hydraulic flow for steering is provided by the steering
swivel to the appropriate ends of the steer cylinders
pump. Flow from the pump is routed through the
as selected by the steering wheel in the cab.
single selector valve to the steer control valve, and
steering selector valve to the appropriate ends of the
The steer selector valve is actuated by the steer
steer cylinders as selected by the REAR AXLE
reversing switch. With the superstructure over the
STEERING control switch on the console. As the
rear of the crane carrier the valve is de-energized.
switch is positioned to the left or right, the
Turning the steering wheel to the right will turn the
appropriate solenoid on the steer control valve is
wheels to the right and turning the wheel to the left
energized to actuate steering in the same direction.
will turn the wheels to the left. This causes the crane
A gauge on the console indicates the positioning of
to turn in the direction the steering wheel is turned.
the wheels.
Rotating the superstructure over the front of the
carrier actuates the steer reversing solenoid, which
FRONT AXLE STEERING FROM THE SUPER-
in turn energizes the solenoid in the steer selector
STRUCTURE.
valve and shifts the valve spool. This reverses the
flow of oil to the steer cylinders on the rear axle thus
For front axle steering from the superstructure the
turning the steering wheel to the right will turn the
steering mode control handle must be pulled out.
wheels to the left and turning the steering wheel to
the left will turn the wheels to the right. This allows
Hydraulic flow is provided by the third section of the
the crane to turn in the direction the steering wheel is
hydraulic pump. Flow from the pump is routed to the
turned whether the superstructure is facing the front
integrated outrigger valve. As the control switch in
or the rear of the carrier.
the cab is positioned to the left or right, the
applicable solenoid on the integrated outrigger valve
is energized and hydraulic oil is routed through the
double selector
MAINTENANCE
irregularities or sticky sensation. This may indicate
FUNCTIONAL CHECK.
dirt in the fluid.
A normal periodic functional check of the entire
power steering system will generally be adequate to
3. Ensure the system has adequate power. If there
ensure satisfactory service.
is an indication of ``hard steering'', this can be
caused by either a reduced oil flow to the control
1. Check all fittings for leakage. An accumulation of
valve or a reduced system relief pressure. Adequate
moist, black dirt is a good indication of leakage.
oil flow under all conditions can best be checked by
timing the full travel of the cylinder with the steered
2. Actuate the control lever, and turn the steering
axle unloaded and loaded. If there is a great
wheels through their full range of travel, with the
difference at low engine speed and slight difference
engine running at idle, and at full throttle, and with
at high engine speeds this may indicate a defective
the crane standing still, and moving. Note any speed
pump drive. Adequate oil pressure can only be
2-5-4
