94XJ_19.PDF

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STEERING
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STEERING
CONTENTS
page
page
GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1
MANUAL STEERING GEAR . . . . . . . . . . . . . . . 35
NON-TILT STEERING COLUMN . . . . . . . . . . . . 50
POWER STEERING PUMP . . . . . . . . . . . . . . . . . 9
POWER STEERING SYSTEM DIAGNOSIS . . . . . 3
RECIRCULATING BALL POWER STEERING GEAR . 19
STEERING COLUMN GENERAL SERVICE . . . .
STEERING LINKAGE—XJ . . . . . . . . . . . . . . . . .
STEERING LINKAGE—YJ . . . . . . . . . . . . . . . . .
STEERING RHD . . . . . . . . . . . . . . . . . . . . . . . .
TILT STEERING COLUMN . . . . . . . . . . . . . . . .
TORQUE SPECIFICATIONS . . . . . . . . . . . . . . . .
45
14
17
69
59
73
GENERAL INFORMATION
STEERING SYSTEM COMPONENTS
Jeep vehicles can have either a manual or power
steering system (Fig. 1). A recirculating-ball type
steering gear is used for both systems.
Power steering systems use;
•
Steering gear
•
Pressure and return fluid hoses and fittings
•
Belt driven steering pump
•
Integral or remote body mounted pump reservoir
plied by the pump. Manual steering is always avail-
able at times when the engine is not running or in
the event of pump or belt failure. Steering effort is
higher under such conditions.
The steering stub shaft, rotary valve, worm shaft,
and rack piston assembly are all in line. The oil pas-
sages are internal within the gear housing except for
pressure and return hoses between the gear and
pump.
The power steering gear has a recirculating ball
system. This acts as a rolling thread between the
worm shaft and rack piston. The worm shaft is sup-
ported by a thrust bearing at the lower end and a
bearing assembly at the upper end. When the worm
shaft is turned right, the rack piston moves up in
gear. Turning the worm shaft left moves the rack
piston down in gear. The rack piston teeth mesh with
the sector, which is part of the pitman shaft. Turning
the worm shaft turns the pitman shaft, which turns
the wheels through the steering linkage.
The control valve in the steering gear directs the
power steering fluid to either side of the rack piston.
The rack piston is assisted by hydraulic pressure. If
the steering system loses hydraulic pressure, the ve-
hicle can be controlled manually, but with higher
steering effort.
An identification code located on the side cover des-
ignates the gear ratio (Fig. 2).
•
Code BH designates 14:1 ratio used in XJ vehicles
•
Code BF designates 13-16:1 ratio used in YJ vehi-
cles
A recirculating-ball steering gear is used with the
power (assisted) steering system (Fig. 1). The power
steering gear can be adjusted and internally serviced.
Fig. 1 Steering Gears
POWER STEERING GEAR
The steering gear is mounted on the left frame rail.
The gear is joined to the intermediate shaft by a uni-
versal joint coupling. The coupling helps isolate noise
and road shock from the interior.
The major internal components of the gear are the:
•
Rotary valve assembly
•
Steering worm shaft
•
Rack piston assembly
•
Pitman shaft
The movement of these parts, while turning or
parking, is aided by hydraulic pressure and flow sup-
POWER STEERING PUMP
Hydraulic pressure is provided for operation of the
power steering gear by a belt driven power steering
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STEERING
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Fig. 2 Ratio Code Location
pump. The power steering pump is a constant flow
rate and displacement, vane-type pump. The internal
parts in the housing operate submerged in fluid. The
flow control orifice is part of the high pressure line
fitting. The pressure relief valve inside the flow con-
trol valve limits the pump pressure.
Power steering pumps have different pres-
sure rates and are not interchangeable with
other pumps.
The power steering pump is connected to the steer-
ing gear via high pressure and return hose. The
pump shaft has a pressed-on drive pulley that is belt
driven by the crankshaft pulley (Fig. 3).
XJ vehicles with 2.5L engines and all YJ vehicles:
The reservoir is mounted at the front left side of the
engine compartment. XJ vehicles equipped with a
4.0L engine have the reservoir attached to the pump
body with spring clips.
Fig. 3 TC Series Pump With Integral Reservoir
STEERING COLUMNS
Two general types of steering columns are installed
on Jeep vehicles: a fixed, non-tilt column and a tilt
column (Fig. 4).
The ignition key/lock cylinder is located in the
steering column. When the key/lock cylinder is
turned to the LOCK position, the ignition switch and
steering shaft cannot be operated. For vehicles with
an automatic transmission, the lock mechanism also
prevents operation of the gear shift mechanism.
Fig. 4 Steering Columns
The center, slip-type intermediate shaft is attached
to the steering gear and steering column shaft with
universal joints.
Both types of steering columns have anti-theft pro-
visions. They are energy-absorbing.
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POWER STEERING SYSTEM DIAGNOSIS
PUMP PRESSURE TEST
(1) Check belt tension and adjust as necessary.
(2) Disconnect high pressure hose at gear or pump.
Use a container for dripping fluid.
(3) Connect Gauge 7617 (J21567) to both hoses us-
ing adapter fitting (Fig. 1). Connect spare pressure
hose to gear or pump.
STEERING
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CAUTION: The following test procedure involves
testing maximum pump pressure output and flow
control valve operation. Do not leave valve closed
for more than 5 seconds as the pump could be
damaged.
(8) Close valve fully three times and record highest
pressure indicated each time.
All three readings
must be above specifications and within 345
kPa (50 psi) of each other.
•
Pressures above specifications but not within 345
kPa (50 psi) of each other, replace pump.
•
Pressures within 345 kPa (50 psi) of each other
but below specifications, replace pump.
CAUTION: Do not force the pump to operate against
the stops for more than 2 to 4 seconds at a time.
Pump damage will result.
(9) Open the test valve, turn steering wheel ex-
treme left and right positions against the stops.
Record the highest indicated pressure at each posi-
tion. Compare readings to specifications. If highest
output pressures are not the same against either
stop, the gear is leaking internally and must be re-
paired.
Fig. 1 Pressure Test Gauge
(4) Open the test valve completely.
(5) Start engine and let idle.
(6) Check fluid level, add fluid as necessary.
(7) Gauge should read below 862 kPa (125 psi), if
above, inspect the hoses for restrictions and repair as
necessary. The initial pressure should be in the
range of 345-552 kPa (50-80 psi).
PUMP OPERATING SPECIFICATIONS
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STEERING
POWER STEERING SYSTEM DIAGNOSIS
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POWER STEERING SYSTEM DIAGNOSIS
STEERING
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