Chevrolet 1980 Light Duty Truck Service Manual page 202

3B3-4 POWER STEERING SYSTEM
CONDITION
Pump growl
Note: Most noticeable at full
wheel travel and stand still parking
Swish in pump
Whine in pump
Squawk in gear (not belt)
SYSTEM OPERATION
Excessive wheel kick-back or loose
steering.
Poor return of steering.
POSSIBLE CAUSE
Scored pump pressure plates, thrust
plate or rotor.
Extreme wear of pump cam ring.
Defective pump flow control valve
Pump shaft bearing scored.
Damper " O" ring on valve spool cut
Backlash in steering linkage.
Air in system.
Excessive "over-center" lash.
Loose thrust bearing preload adjust­
ment.
Worn poppet valve (Gear)
Steering gear loose on frame.
Steering gear flexible coupling too
loose on shaft or rubber disc mounting
screws loose.
Steering linkage ball studs worn
enough to be loose.
Front wheel bearings incorrectly ad­
justed or worn.
Tires under-inflated.
Lower coupling flange rubbing against
steering gear adjuster plug.
Steering wheel rubbing against direc­
tional signal housing.
Tight or frozen steering shaft bearings.
Steering linkage or ball joints binding.
Steering gear to column misalignment.
Tie rod pivots not centralized.
Lack of lubricant in suspension ball
joints and steering linkage
Fig. 3 B 3 -3 ~ P o w e r Steering System D iagnosis C hart B
CORRECTION
Replace affected parts, flush system.
Replace affected parts.
Replace valve
Replace housing and shaft, flush system
Replace "0 " ring.
Adjust parts affected or replace worn
parts.
Add oil to pump reservoir and bleed by
operating steering. Check all connections.
Adjust to specification.
Adjust to specification.
Replace poppet valve.
Tighten attaching bolts to 70 foot­
pounds.
Tighten flange pinch bolts to 30 foot­
pounds, if serrations are not damaged.
Tighten upper flange to coupling nuts
to 20 foot-pounds.
Replace loose components.
Adjust bearings or replace with new
parts as necessary.
Inflate to specified pressure.
Loosen pinch bolt and assemble prop­
erly.
Adjust steering jacket.
Replace bearings.
Replace affected parts.
Align steering column.
Adjust tie rod ends as required to
center pivots.
Lubricate and relubricate at proper
intervals
LIG H T T R U C K S ER V IC E M ANUAL