GMC 1989 Light Duty Truck Repair Manual page 128

3B3-14 POWER STEERING
10. REM OVE AND IN STA LL C H EC K
VALVE
R EM O V E
1. R e m o v e p a rts a s s h o w n .
R e m o v e c h e c k valve.
In sta ll c h e c k valve.
11. ADJUST T H R U S T
A. B e fo r e a d ju s tin g
b e a rin g p re lo a d ,
ro ta te th e s tu b sh a ft
b a c k a n d fo rth to
d ra in all o il fro m
gear.
B. U sing sp a n n e r w rench
J-7 6 2 4 , tighten adjuster
plug until thrust
bearing is firmly
bottom ed, 27 N ew ton
M e tres (22 Ft. L b s ).
M a rk h o u s in g a n d
fa c e o f a d ju s te r
p lu g . -------------------
T u rn a d ju s te r
c o u n te r c lo c k w is e u n til
m a rk o n fa c e o f a d ju s te r
lin e s u p w ith s e c o n d
m ark o n h o u s in g . ___
Figure 27— Removing and Installing the Check Valve and Adjusting the Thrust Bearing Preload and Pitman Shaft
IN STA LL
1. In sta ll p a rts as s h o w n
W ith s m a ll sc re w d riv e r, p ry
c h e c k v a lve fro m h o u s in g .
C a r e s h o u ld b e ta ke n no t to
d a m a g e th re a d s w h en p ry in g
o n e d g e o f h o u s in g .
U s in g a p ie c e of
% tu b in g , 4 in c h e s
lo n g , c a r e fu lly
d riv e th e c h e c k
v a lve in to the
h o u sin g .
BEARING PRELOAD
M e a s u re b a c k
c o u n te r c lo c k w is e
13m m (V ") a n d p la c e a
2
s e c o n d m ark o n h o u s in g
U s in g p u n c h in n o tc h
tig h te n lo c k nut s e c u re ly .
H o ld a d ju s te r p lu g to
m a in ta in a lig n m e n t o f
th e m arks.
" Over-Center" Sector
12. PITM AN SHAFT "OVER-CENTER
SECTOR ADJU STM EN T
W h e n g e a r is o n c e n te r
flat o n s tu b sh a ft is
n o rm a lly o n sa m e s id e as,
an d p a ra lle l w ith, s id e cover.
T h e b lo c k to o th o n th e P itm a n
sh a ft is in lin e w ith th e
o v e r-c e n te r p re lo a d adjuster. -
B. B a c k o ff p re lo a d a d ju ste r
u n til it s to p s , th e n turn
it in o n e fu ll tu r n .- i
W ith g e a r at c e n te r
of travel, c h e c k to rq u e
to tu rn stu b s h a ft
(re a d in g #1).
\
C. Turn adjuster in until
torque to turn stub shaft
is 0.6 to 1.2 N ew ton M etres
(6
to 10 in. Lbs.)
m ore than reading # 1 . ------
T o rq u e adjuster lock
nut to 27 N ew ton M etres
(20 Ft. Lbs.) --------------
P re v e n t a d ju s te r s c re w
fro m tu rn in g w h ile
to rq u e in g lo c k nut.
F-06801