GMC 1990 Light Truck Repair Manual page 127

10. REMOVE AND INSTALL CHECK
VALVE
REMOVE
1 . R em o ve p a rts a s sh o w n .
With sm all screw d river, pry
c h e c k valve from h ou sin g
C a r e sh o u ld b e taken not to
d a m a g e thread s w hen prying
on e d g e of housin g.
R em o ve c h e ck valve.
Install c h e c k valve
11. ADJUST THRUST BEARING PRELOAD
A . B e fo re ad ju stin g
b earing preload,
rotate the stu b shaft
back and forth to
drain all oil from
gear.
B. Using spanner wrench
J - 7 6 2 4 , tighten adjuster
plug until thrust
bearing is firmly
bottomed, 2 7 Newton
M etres (2 2 Ft. Lbs.).
Mark h o u sin g and
fa c e of ad ju ster
plug. --------------------
Turn ad ju ster
c o u n te rclo ck w ise until
m ark on fa ce of adjuster
lines up with s e c o n d
m ark on hou sin g. ___
Figure 27—Removing and Installing the Check Valve . Adjusting the Thrust Bearing Preload and Pitman
I N S T A L L
1. Install parts a s sh o w n
U sing a p ie ce of
% tubing, 4 in ches
long, carefu lly
drive the ch e ck
valve into the
housing.
M e asu re back
co u n te rclo ck w ise
13 m m (Vi") and p la ce a
s e c o n d mark on hou sin g
U sin g p u nch in notch
tighten lock nut se cu re ly
Hold ad ju ster plug to
maintain alignm ent of
the marks.
Shaft "Over-Center" Sector.
POWER STEERING 3B3-13
PITMAN SHAFT "OVER-CENTER'
SECTOR ADJUSTMENT
W hen g e a r is on cen ter
flat on stub shaft is
norm ally on sam e side a s,
and parallel with, sid e cover.
T h e b lock tooth on the Pitman
shaft is in line with the
ove r-cen ter preload adjuster. -
B. B a c k o ff preload adjuster C. Turn adjuster in until
until it sto p s, then turn
it in one full turn .-i
With g e a r at center
of travel, c h e ck torque
to turn stub shaft
(reading # 1 ) .
\
torque to turn stub shaft
is 0.6 to 1 .2 Newton Metres
(6 to 1 0 in. Lbs.)
more than reading # 1 . -------
Torque adjuster lock
nut to 2 7 Newton Metres
(20 Ft. Lbs.) ---------------
Prevent ad ju ster s c r e w
from turning w hile
torqueing lock nut.
F6801