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CHRYSLER SERVICE MANUAL
STEERING—401
FLOW CONTROL VALVE (CLOSED)
PRESSURE RELIEF
VALVE
HIGH PRESSURE - LOW FLOW
FLOW CONTROL VALVE (OPEN)
PRESSURE RELIEF
VALVE (CLOSED)
LOW
PRESSURE - HIGH FLOW
•FLOW CONTROL VALVE (OPEN)
PRESSURE RELIEF
VALVE (OPEN)
HIGH PRESSURE - HIGH FLOW
53x632
Fig.
12—Pump Pressure and Flow
A rack, machined in the lower portion of the
lower piston rod, meshes with a sector gear.
This combination produces rotation of the steer-
ing gear arm and thereby actuates the steering
linkage.
The hydraulic system of the Coaxial gear con-
sists of a double-acting piston, a valve (which
fits inside the piston), and a hydraulic reaction
chamber (which gives the driver the "feel" of
the road). Axial positioning of the valve directs
high pressure oil to one side or the other of the
double-acting piston. At the same time, valve
movement opens an oil return line which carries
oil from the low pressure side of the piston to
the oil reservoir. The direction of oil flow (which
depends upon the direction of steering wheel
rotation) is such that hydraulic force is added to
the driver's effort and is transmitted through the
rack and sector gear to the steering gear arm.
Other components of the hydraulic system
are, a generator-driven oil pump with pressure
relief valve and flow control valve, and a filter
with the oil reservoir. The flow control valve
limits the oil flow to a predetermined maximu^n
(IV2 gallons per minute) and thus holds tHe
horsepower required to drive the oil pump to a
minimum.
a. Power Steering Oil Pump, Reservoir and
Assembly
The oil pump and reservoir assembly is
mounted at the rear end of the generator. A
cartridge-type filter element is located in the
reservoir. Oil from the steering gear assembly
flows through an internal passage in the pump
body, through the full-flow oil filter, and into
the reservoir chamber. From the reservoir, oil
enters the oil pump intake (Fig. 12). The posi-
tion of the oil pump is adjustable to help main-
tain level fluid in reservoir when drive belt is
adjusted.
A small diaphragm vent valve in the reser-
voir cover is forced open to provide a passage to
the atmosphere, if excessive pressure occurs in
the reservoir.
With cold oil, insufficient oil would pass
through the filter to the reservoir, and the oil
pressure would build-up in the line from the
steering gear assembly. Therefore, a spring-
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