Hummer H1 Service Manual page 522

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®
INSTALLER
TOOL
J–6219
GEAR
HOUSING
Figure 8-51: Pitman Shaft Seal Installation
Rack Piston Assembly
1. Lubricate rack piston bore in gear housing and new O-ring
and seal ring with power steering fluid.
2. Install new backup O-ring in rack piston seal groove.
3. Install new teflon seal ring in groove over backup O-ring
(Figure 8-52).
TEFLON RING
NOTE: BACK-UP
O-RING IS INSTALLED
UNDER SEAL RING
RACK PISTON
Figure 8-52: Rack Piston Seal Ring Installation
05745159
Steering System
4. Install wormshaft in rack piston. Wormshaft flange should
be seated against piston as shown (Figure 8-53).
LOAD BEARING BALLS
INTO THIS BALL GUIDE PORT
RACK
PISTON
Figure 8-53: Rack Piston Loading Port
For Bearing Balls
5. Align worm shaft spiral groove with indicated ball guide
circuit port in rack piston (Figure 8-53).
6. Load recirculating bearing balls in rack piston and in ball
guides as follows:
a. Lubricate bearing balls with power steering fluid.
b. Turn wormshaft counterclockwise to load bearing
balls in rack piston.
c. Load balls in rack piston through indicated ball guide
port (Figure 8-53).
d. Load balls alternately. Start with chrome ball
followed by black ball until rack piston is full (piston
will only accommodate around 18 balls).
e. Load remaining balls in ball guides. Use petroleum
jelly to hold balls and guide halves in place
(Figure 8-54).
f. Verify that 12 black and 12 chrome balls were
installed in correct sequence.
g. Assemble and install ball guides (with enclosed balls)
on rack piston and secure guides with clamp. Tighten
clamp bolts to 43 lb-ft (58 N•m) torque.
WARNING: The chrome recirculating balls are
slightly larger in diameter than the black coated balls.
This is required in order to generate and maintain
proper wormshaft preload. It is also why the balls must
be installed alternately. Incorrect installation, or failure
to load all 24 balls will result in loss of preload, bind,
and partial loss of steering control. Verify that the balls
are correctly loaded before proceeding.
8-31
WORMSHAFT
FLANGE
4-1-00