GMC 1982 Light Duty Truck Service Manual page 258

3B3-2 POWER STEERING SYSTEM
P O W E R S T E E R IN G P U M P
1 DRIVE SHAFT
2 SEAL
3. SEAL, Reservoir " O" Ring
4. HOUSING ASSEMBLY
5 SEAL
6. PIN, Pump Ring Dowel
7. PLATE, Thrust
8 CAP, Filler
9 VALVE ASSEMBLY, Flow Control
10. SPRING, Flow Control
11 SEAL
12 ROTOR, Pump
D IA G N O S IS (F IG S . 3 B 3 - 3 T H R O U G H 3 B 3 - 8 )
Complaints of faulty steering are frequently the result
of problems other than the steering gear or pump. Those
areas of the steering system which can be easily checked and
quickly corrected without disassembly and overhaul of any
major components should be attem pted first.
Conditions such as hard or loose steering, road shock or
vibrations are not always due to the steering gear or pump,
but are often related instead to such factors low tire pressure
and front end alignment. These factors should be checked
and corrected before any adjustm ent or disassembly of the
power steering gear or pump is attempted.
13. RING, Shaft Retainer
14. VANE KIT, Rotor
15. RING KIT, Pump Rotor
16. PLATE, Pressure
17. SPRING, Pressure Plate
18. PLATE, Pump Housing End
19 RING, End Plate Retaining
20. SEAL, Reservoir
21. RESERVOIR ASSEMBLY
22. BOLT
23. SEAL
24. FITTING, W Orifice
Fig. 3B3-2 -- Pump and G e a r Cross-Section
S y s te m C h ecks
Many factors affect power operation of the steering
system, of which the most common are:
1. Fluid level and condition.
2. Drive belt tension.
3. Loose component mountings.
4. Loose pump pulley.
These factors must be checked and corrected before
making any further diagnosis of the steering system. The
need for proper diagnosis cannot be over-emphasized.
A fter the source of the problem has been found,
determine the cause. For example, if the oil level in the
reservoir is found to be low, refill and check the entire
hydraulic system for oil leaks. Refilling the reservoir will not
necessarily correct the problem.