TM 10-3930-641-34-2
STEERING SYSTEM (CONT)
(Sheet 2 of 4)
Steering system can be divided into two groups: steering group and
5.
STEERING CONTROL VALVE. Directs high pressure oil to the front
supplemental steering group.
of one cylinder and to the rear of the opposite cylinder. Direction of the
1.
HYDRAULIC OIL TANK. The storage reservoir for all of the hydraulic
steering wheel will determine which cylinder is pressurized in the front
or rear. The control valve is hydraulically activated by the hand
oil used in the machine except for the transmission and torque
metering unit.
converter. An inlet strainer provides filtering when adding or replacing
oil to the tank. Also, a filter is built into the tank for filtering all of the oil
6.
STEERING CYLINDERS (2). Are activated by the high pressure oil
returning from the hydraulic system. Oil is pumped from the tank
through the steering components and re- turned back to the tank.
from the control valve. A left turn will cause the left cylinder to shorten
and the right cylinder to lengthen. The changing lengths of these
cylinder causes the vehicle to turn.
2.
HYDRAULIC OIL LINES. Serves as passages for the pressurized oil
7.
STEERING WHEEL AND COLUMN. Adjustable to eight different
to operate the different steering components.
positions. Seven of the positions are for operator comfort, while the
3.
HYDRAULIC PUMP. The hydraulic pump serves two systems, steering
eighth and most forward is for storing and locking the wheel when not in
use. Pushing the wheel into the store position also moves the
and braking. A positive displacement gear type pump driven by the
transmission control lever to NEUTRAL.
engine. The larger section of the pump supplies high pressure oil to
operate the steering system. The oil is drawn from the oil tank and
8.
HAND METERING UNIT (HMU). Attached to the steering wheel with a
pumped through the steering system and returned to the tank.
shaft. It is a small hydraulic pump which meters and directs oil into the
steering control valve as the wheel is turned.
4.
FILTER. Protects the system in the event of a pump failure. It is a
9.
NEUTRALIZER VALVES (2). Stops the flow of pilot oil to the steering
replaceable screen type.
control valve at the end of a complete turn in either direction. This
stops the steering action before the machine turns against the frame
stops. The valves are normally open, allowing flow through them.
Go on to Sheet 3
6-3
