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POWER STEERING COMPONENTS TRW ROSS 3B3-1
SECTION 3B3
POWER STEERING COMPONENTS
(TRW ROSS)
NOTICE: When fasteners are removed, always reinstall them at the same location from which they were
removed. If a fastener needs to be replaced, use the correct part number fastener for that application. If
the correct part number fastener is not available, a fastener of equal size and strength (or stronger) may
be used. Fasteners that are not reused, and those requiring thread locking compound will be called out.
The correct torque value must be used when installing fasteners that require it. If the above conditions
are not followed, parts or system damage could result.
CONTENTS
SUBJECT
PAGE
General Description.......................................................:......................... ............................................ .......... . 3B3- 1
Disassembly.......................... ...................... .................... ............... ............... ................ ................ ................ 3B3- 1
Valve Housing and Input Shaft Assembly.......
.... ........
.............
.........
.... .............. 3B3- 5
Inspection........................................... ..I.............. ............................... ...................................... .............. .............. 3B3- 6
Assembly...................................................... .................. ..................... .............................................. ............... ...3B3- 6
Valve Housing and Input Shaft Assembly...............
......... ................... ........... ...............................3B3- 6
Steering Gear........................................ ................ ........................................................................ ............... 3B3- 7
Adjustment..................... ................. .......................... ........................ ................ .................. ...........................3B3-10
Specifications................... ...................... ...................... ......:.................. ............ ............ .................................... 3B3-11
Fastener Tightening Specifications..........
................. ............................................... ......... . 3B3-11
Special Tools....................... L-............. .............................. ;V............... .................. ................... .......................
3B3-11
GENERAL DESCRIPTION
The TRW Ross integral hydraulic power steering gear
has a gear box that contains a manual steering mecha
nism, a hydraulic control valve, and a hydraulic power
cylinder.
When the steering wheel is turned, force is transmit
ted from the steering wheel to the steering gear input
shaft. A torsion bar, pinned at one end to the input shaft
and at its other end to the worm shaft, turns with the
input shaft and exerts a rotational force on the worm
shaft. In response to this rotational force, the, worm
shaft, acting through the recirculating ball mechanism,
tries to move the rack piston axially through the gear
housing cylinder bore.
The axial movement of the rack piston is resisted by
its engagement to the sector shaft, which is connected
by linkage to the steered wheels. Because of this resis
tance, the torsion bar is twisted by the input shaft,
thereby actuating the control valve. Pressurized fluids
directed by the control valve assist in moving the rack
piston axially through the cylinder bore. The rack piston
then turns the sector shaft to steer the vehicle.
Road shock forces are transmitted through the sector
shaft to the rack piston, and to the worm shaft. The
internal geometry of the gear causes the control valve
to send high pressure fluid to the correct cylinder cavity
to resist the shock forces. By absorbing the shock
forces hydraulically, the steering gear prevents objec
tionable kickback at the steering wheel.
The gear is equipped with an unloading valve (pop
pet) at each end of the rack piston. When the steered
wheels approach the axle stops, it will open and reduce
pressure in the gear to reduce heat build up. The
valves also reduce forges on the steering linkage.
.These valves will automatically set to the axle stops
after installation in the vehicle.
A relief valve limits maximum supply pressure to pro
tect the power steering pump but does not reduce pres
sure as the steered wheels approach the axle stops.
DISASSEMBLY
Remove or Disconnect (Figures 1, 2, 4, and 5)
Tools Required:
J 36452-A Poppet Seat Tool
J 37071 Bearing and Seal Tool
1. Seal (37) using a small screwdriver.
• Rotate the input shaft, valve worm assembly
(14) until the timing mark on the end of the
sector shaft is in line with the timing mark on
the end of the housing trunnion.
Summary of Contents for C Series 1993
Page 1: ......
Page 12: ...OA 6 GENERAL INFORMATION Figure 11 Allison Transmission I D Location ...
Page 44: ...3B1A 2 POWER STEERING GEAR UNIT REPAIR Figure 1 710 Power Steering Gear ...
Page 62: ......
Page 75: ...3B3 2 POWER STEERING COMPONENTS TRW ROSS ...
Page 121: ...5H 16 AIR BRAKE VALVES Figure 21 Bendix Proportioning Relay Valve Components ...
Page 147: ...5J 10 AIR COMPRESSOR AND GOVERNOR 286 F9051 Figure 18 Bendix BX 2150 Compressor Components i ...
Page 204: ...MODEL 295 TBI UNIT 6C1 3 F7973 Figure 3 Model 295 TBL Unit ...
Page 251: ...6D4 6 37 MT STARTER MOTORS V3022 Figure 8 37 MT Components ...