Chevrolet 10 Series 1968, Руководство по обслуживанию

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STEERING 9-2
1. On Chevy Van and 10, 20 and 30 series trucks, re­
move pitman arm nut and mark relation of pitman
arm position to sector shaft. Remove pitman arm.
Use Tool J-5504 for Chevy Van, J-6632 or J-5504
(fig. 2) for 10, 20 and 30 Series. On 40, 50 and 60
Series Trucks, remove steering connecting rod from
pitman arm.
2. Disconnect horn wire at mast jacket and remove
horn button cap from center of steering wheel.
3. Loosen the pitman shaft lash adjuster screw locknut
and turn the adjuster screw a few turns in a counter­
clockwise direction (fig. 3). This removes the load
imposed on the worn bearings by the close meshing
of rack and sector teeth. Turn steering wheel gently
in one direction until stopped by gear, then turn
wheel back exactly half way to center position.
CA U TIO N : Do not turn steering wheel hard
against stops when steering relay rod is dis­
connected as damage to ball guides may result.
4. Using an inch pound torque wrench and socket on
steering wheel nut, measure torque required to keep
the wheel in motion. If torque does not lie within
limits given in specifications section, worm bearing
preload adjustment is necessary.
5. To adjust worm bearings, loosen worm bearing ad­
juster locknut and turn worm bearing adjuster shown
in Figure 3 until there is no perceptible end play in
worm. Check torque at steering wheel, readjusting
if necessary to obtain proper torque. Tighten lock-
nut and recheck torque. If the gear feels "lumpy”
after adjustment of worm bearings, there is probably
damage in the bearings due to severe impact or to
improper adjustment and the gear must be disas­
sembled for replacement of damaged parts.
6 . After proper adjustment of worm is obtained, and all
mounting bolts securely tightened, adjust lash ad­
juster screw. First turn the steering wheel gently
from one stop all the way to the other, carefully
counting the total number of turns. Then turn wheel
back exactly half way, to center position. Turn lash
adjuster screw clockwise to take out all lash in gear
teeth, and tighten locknut. Check torque at steering
F ig. 2 —Removing Pitman Arm
Fig. 3 —Steering G ear Adjustment Points (T yp ica l)
wheel, taking highest reading as wheel is turned
through center position. See Specifications for proper
sector lash adjustment. Readjust if necessary to
obtain proper torque.
NOTE: If maximum specification is exceeded,
turn lash adjuster screw counter-clockwise, then
come up on adjustment by turning the adjuster in
a clockwise motion.
7. Tighten locknut then recheck torque as it must lie
between specified limits.
8 . On 10, 20 and 30 Series trucks reassemble pitman
arm to sector shaft, lining up marks made on dis­
assembly. Torque nut to specifications. On 40, 50
and 60 Series trucks assemble steering connecting
rod to pitman arm.
9. Install horn cap or ornament and connect horn wire
at chassis connector.
Steering Gear High Point Centering—C-Pl 0-20-30
1. Set front wheels in straight ahead position. This can
be checked by driving vehicle a short distance on a
flat surface to determine steering wheel position at
which vehicle follows a straight path.
2. With front wheels set straight ahead, check position
of mark on wormshaft designating steering gear high
point. This mark should be at the top side of the
shaft at 12 o'clock position and lined up with the
mark in the coupling lower clamp.
3. If gear has been moved off high point when setting
wheels in straight ahead position, loosen adjusting
sleeve clamps on both left and right hand tie rods,
then turn both sleeves an equal number of turns in
the same direction to bring gear back on high point.
CA U TIO N :
Turning the sleeves an unequal
number of turns or in different directions will
disturb the toe-in setting of the wheels.
4. R e a d j u s t toe-in as outlined in Section 3 (if
necessary).
Steering Wheel Alignment
NOTE:
On C-P10-C20-30 series units check
WORM
ADJUSTER
\
..
LASH ADJUSTER x
SCREW
T O O L—J-5504
T O O L—J-6632
CHEVROLET TRUCK SERVICE MANUAL