GMC 1990 Light Truck Repair Manual page 126

3B3-12 POWER STEERING
. DISASSEMBLE AND ASSEMBLE RACK
8
PISTON
DISASSEMBLE
1. D isassem ble parts
as shown
2. Clean and inspect
all p arts for
e x c e s s iv e w ear
r T EFL O N S E A L AND O RING—
If replaced lubricate new seal
and "O " ring with pow er
steerin g fluid
Turn worm until worm groove
is aligned with the lower
ball return guide hole
Befo re a ssem b lin g rack
in hou sin g, ball retainer
J - 2 1 5 5 2 must be inserted
into rack to allow
rem oval of worm.
Figure 26—Removing and Installing the Rack Piston and Pitman Shaft Seals and Bearing
ASSEMBLE
1 Assem b le parts
as shown
NOTICE:
The black
balls are smaller than the
stiver balls The black
and silver balls must be
installed alternately into
the rack-piston and
return guide to maintain
rack piston to worm gear
preload
W O RM — Slide all the way
Lubricate balls with
power steering fluid.
Install balls, through
ball return guide hole,
while rotating worm
counterclockw ise
GUIDE — Alternately
install remainder of
balls and retain with
grease at each
end of guide
CLA M P
SCR EW -Tighten
to 5 Newton Metres
(4 Ft Lbs.)
9. REMOVE AND INSTALL PITMAN SHAFT
SEALS AND BEARING
REMOVE
1. Coat seal lip and washer face
1. Clean end of housing
with anhydrous calcium grease.
thoroughly to prevent dirt
from entering and be
2. Install parts as shown.
extremely careful not to
score the housing bore.
2. Use screw driver to
remove pitman shaft
dust seal
3. Remove retaining ring
N EED LE BEARIN G
with snap ring pliers
J-4 2 4 5 . R em ove only if it
4. Using screw driver, pry
needs replacing
seals and washers
from bore
S E A L BACK-UP
W ASH ER
PITMAN SH AFT
D U ST SE A L
Removing bearing
r ~ ~
When tool bottom s on
housing bearing is
fully installed
---- J
Install Pitm an shaft bearing Install Pitm an shaft seals.
INSTALL
HOUSING A S SE M B L Y
Inspect for burrs
RETAIN ING
R IN G
PITMAN SH A FT S E A L — 1
F6803