Pontiac tempest 1968 Service Manual page 588

S T E E R I N G
9-31
H H H P
• i
• • i f
STUB SHAFT-
TORSION BAR -
F i g . 9-54 Tapping to Loosen Valve Spool
If unit parts are scored or damaged the entire rotary
valve assembly is to be replaced.
NOTE; If the valve spool dampener O-ring re­
quires replacement, perform the following op­
erations,
1. Work spool spring onto bearing diameter of
stub shaft and remove spool spring.
2. Tap end of stub shaft assembly gently against
workbench to remove valve spool (Fig. 9 - 5 4 ) .
CAUTION: The diametrical clearance between the
valve body and spool may be as low as .0004".
The slightest cocking of spool may jam it in valve
body (Fig. 9-55).
It slight sticking occurs, make a gentle attempt to
reverse the removal procedure. If this does not free
the spool, It has become cocked In valve body bore
and may be removed later.
3. Remove and discard valve spool dampener O-
ring.
V A L V E S P O O L
D A M P E N E R " O " R I N G
R O T A R Y V A L V E
-VALVE SPOOL SPRING
^ — V A L V E SPOOL DAMPENER ( " O " RING)
j ROTARY VALVE
4
< , i TORSION BAR
VALVE SPOOL-
ROTARY VALVE (TEFLON) RINGS
TORSION BAR AND STUB SHAFT ASSEMBLY-
F i g . 9-55 Removing V a l v e Spool from Rotary Valve
Fig. 9-56 Exploded View of Rotary Valve
4. Remove stub shaft, torsion bar (small diameter
bar extending through stub shaft) and valve cap as­
sembly by tapping end of torsion bar lightly with a
plastic hammer. This will dislodge the cap from
valve body cap pin (Fig. 9-56). Do not disassemble
stub shaft assembly. The parts are pinned together
and are serviced as an assembly.
5. If valve spool has become cocked as described
in step 3, it can now be freed as follows:
a. Inspect parts to determine in which direction
the spool is cocked.
b. A few very light taps with a soft plastic or
rawhide hammer should align and free the spool
in the bore.
c. Remove and discard O-ring dampener seal
from valve spool.
6. Carefully remove and discard valve body Teflon
rings and ring back-up O-ring seals.
DISASSEMBLE HOUSING
1. Remove pitman shaft outer dust seal back-up
washer retaining ring, using Truarc pliers.
2. Remove outer dust seal back-up washer.
3. Remove seal (double lip) by inserting offset
screwdriver between seal and back-up washer and
prying out of housing.
CAUTION: Do not damage housing bore when re­
moving seal.
4. Remove back-up washer.
5. Remove seal (single lip) by cutting and col­
lapsing seal.
CA UTION: Do not damage housing bore when re­
moving seal.