GMC C Series 1993, Repair Manual

Page: 46 / 264

3B1A-4 POWER STEERING GEAR UNIT REPAIR
/
3. O -ring seal (11). ;i
• Turn the stub shaft counterclockwise; until
the rack piston (50) covers the crossover hole
(see: Figure 4).
Important
Aluminum square drive head (8), rap the plug
sharply using a hammer and brass drift.' Steel
hexagon head (8) do not rap. Remove With a
1" socket. ;'rji
; 4.
5.
6
.
, 7.
Plug (8) from rack piston (50). Turn the plug
counterclockwise. /; ;;;
N ut (l)..- i . VV- • - '■/;
Bolts (2). .
. . r.
Side cover (3). Turn adjuster screw on pitman Shaft
(2) clockwise until the side cover (3) separates from
the pitman shaft (5) (Figure 5). >
• Turin stub shaft (31) clockwise untilpitman
shaft teeth (5) and rack pistons (50) and (7)
are disengaged (see Figure 6).
Important
If secondary cylinder plug (12) was forced
out o f housing (6) during step 3, proceed to
step 8.
• Turn stub shaft (31) clockwise until rack
piston (50) bottoms in housing (6).
• Align the end tooth o f the pitman shaft (5)
with the center groove o f the rack piston (50)
and (7) (see Figure 7). ■; ; !
• Turn stub shaft (31) counterclockwise until
the plug (12) separates from the housing (6).
8. Secondary rack piston (7) (see Figure 7).
Important
• D o not remove the plug (8) from the rack
piston (7) during this procedure. Remove
only for replacement.
• Rotate the stub shaft (31) clockwise until the
pitman shaft teeth (5) are free of the rack.
• Turn the pitman shaft until the teeth are
horizontal.
• Insert tool J 21552 into the rack piston bore
with the pilot o f the tool seated into the end of
the worm (33).
• Hold the toot against the worm and turn the
stub shaft counterclockwise. The rack piston;
: ! (50) will be forced onto the tool.
• 1 Hold tool and pull the rackpiston toward the
handle until it touches the tool flange. This
Figure 5 Side Cover Removal
Figure 6 Disengaging the Pitman Shaft Gear Assembly