GMC 1982 Light Duty Truck Service Manual page 266

3B3-10 POWER STEERING SYSTEM
L U B R IC A T IO N O F P O W E R S T E E R IN G P U M P
Check the fluid level in the pump reservoir according to
the intervals listed in Section OB. Use only an approved
power steering lubricant in the pump.
NOTICE: Never use brake fluid in the power steering
pump, or damage may occur.
A D J U S T M E N T S
P o w e r S te e rin g G e a r A d ju s tm e n t P ro c e d u re
Adjustment of the steering gear in the vehicle is not
recom m ended because of the difficulty encountered in
adjusting the worm thrust bearing preload and the confus­
ing effects of the hydraulic fluid in the gear. Since a gear
adjustment is made only as a correction and not as a periodic
adjustment, it is better to take the extra time and make the
adjustment correctly the first time.
Since a handling stability complaint can be caused by
improperly adjusted worm bearings as well as an improper
gear over-center adjustment, it is necessary that the steering
gear assembly be removed from the vehicle and both thrust
bearing and over-center preload be checked and corrected as
necessary. An in-vehicle check of the steering gear will not
pin-point a thrust bearing looseness.
Before any adjustments are made to the steering gear
attem pt to correct complaints of loose or hard steering, or
other wheel disturbances, a careful check should be made of
front end alignment, shock absorbers, wheel balance and
tire pressure for possible steering system problems. See
Diagnosis steps listed earlier in this section.
Once it is determined to make adjustments, refer to
Section 3B of the Overhaul M anual for specific instructions.
S T E E R IN G G E A R H IG H P O IN T C E N T E R IN G
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.
ADJUSTMENT
SLOT
Fig. 3B3-9--Adjusting Pump Position
M A IN TEN A N C E A N D ADJUSTMENTS
PIVOT
BOLTS
2. With front wheels set straight ahead, check position of
mark on worm shaft 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. On C, G and P series, if gear has been moved off high
point when setting wheel in straight ahead position,
loosen the 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.
Turning the sleeves an unequal number of turns or in
different directions will disturb the toe-in setting of the
wheels.
4. On K series, if the gear has been moved off high point
when setting wheels in straight ahead position, loosen
the adjusting sleeve clamps on the connecting rod. Then
turn sleeve to bring gear back on high point.
5. R eadjust toe-in as outlined
necessary).
6. Be sure to properly orient sleeves and clamps, as shown
in Section 3 B 1, when fastening and torqueing clamps to
proper specifications.
P U M P BELT T E N S IO N A D J U S T M E N T
1. Loosen pivot bolt and pump brace adjusting nuts. See
Fig. 3B3-9.
NOTICE: Do not move pump by prying against reservoir
or by pulling on filler neck, or damage to the pump
could occur.
2. Move pump, with belt in place until belt is tensioned to
specifications as indicated by Tool J-23600 (Fig. 3B3-
10). See Figure 3B3-11.
3. Tighten pump brace adjusting nut. Then tighten pivot
bolt nut.
FLU ID LEVEL A D J U S T M E N T
1. Check oil level in the reservoir by checking the dipstick
when oil is at operating te m p e ra tu re. On models
equipped with remote reservoir, the oil level should be
Fig. 3B3-10--Checking Belt Tension with J-23600
in Section 3A (if