Chevrolet 1980 Light Duty Truck Service Manual page 208

3B 3-12 POWER STEERING SYSTEM
5. Start engine and check fluid level adding any fluid
if required. When engine is at normal operating
temperature, the initial pressure read on the gage (valve
open) should be in the 80-125 PSI range. Should this
pressure be in excess of 200 PSI - check the hoses for
restrictions and the poppet valve for proper assembly.
6. Close gate valve fully 3 times. Record the highest
pressures attained each time.
NOTICE: Do not leave valve fully closed for more
than 5 seconds as the pump could be damaged
internally.
a. If the pressures recorded are within the listed specs
and the range of readings are within 50 PSI, the pump is
functioning within specs. (Ex. Spec. 1250 - 1350 PSI -
readings - 1270 - 1275 - 1280).
b. If the pressures recorded are high, but do not repeat
within 50 PSI, the flow controlling valve is sticking. Remove
the valve, clean it and remove any burrs using crocus cloth
or fine hone. If the system contains some dirt, flush it. If
it is exceptionally dirty, both the pump and the gear must
POWER STEERING GEAR
Removal
1. Disconnect hoses at gear. When hoses are
disconnected, secure ends in raised position ot prevent
drainage of oil. Cap or tape the ends of the hoses to prevent
entrance of dirt.
2. Install two plugs in gear fittings to prevent entrance
of dirt.
3. Remove the flexible coupling to steering shaft flange
bolts (G, C and K models) or the lower universal joint pinch
bolt (P models). Mark the relationship of the universal yoke
to the stub shaft.
4. Mark the relationship of the pitman arm to the
pitman shaft. Remove the pitman shaft nut or pitman arm
pinch bolt and then remove the pitman arm from the pitman
shaft using Puller J-6632 (Fig. 3B3-13).
5. Remove the steering gear to frame bolts and remove
the gear assembly.
6. G, C and K Models - Remove the flexible coupling
pinch bolt and remove the coupling from the steering gear
stub shaft.
Installation (Fig. 3B3-14)
NOTICE: See NOTICE on page 1 of this section
regarding the fasteners referred to in steps 1, 3, 4 and
5.
1. Install the flexible coupling onto the steering gear
stub shaft, aligning the flat in the coupling with the flat on
the shaft. Push the coupling onto the shaft until the stub
shaft bottoms on the coupling reinforcement. Install the
pinch bolt and torque to specifications.
The coupling bolt must pass through the
NOTICE:
be
reassembled before further usage.
100 PSI, below the low listed spec., replace the flow control
valve and recheck. If the pressures are still low, replace the
rotating group in the pump.
valve open and turn (or have turned) the steering wheel into
both corners. Record the highest pressures and compare
with the maximum pump pressures and compare with the
maximum pump pressure recorded. If this pressure cannot
be built in either (or one) side of the gear, the gear is leaking
internally and must be disassembled and repaired. See the
current Overhaul Manual.
reconnect pressure hose, check fluid level and/or make
needed repairs.
ON-VEHICLE SERVICE
coupling bolt into the steering shaft flange.
to specifications.
were used, make sure they are buttomed on the pins, tighten
the flange bolt nuts to specifications and then remove the
plastic spacers.
were not used, center the pins in the slots in the steering
shaft flange and then install and torque the flange bolt nuts
to specifications.
completely disassembled,
c. If the pressures recorded are constant, but more than
7. If the pump checks within specifications, leave the
8. Shut off engine, remove testing gauge, spare hose,
shaft undercut, or damage to the components could
occur.
2. Place the steering gear in position, guiding the
3. Install the steering gear to frame bolts and torque
4. If flexible coupling alignment pin plastic spacers
5. If flexible coupling alignment pin plastic spacers
Fig. 3 B 3 -1 3 ~ R e m o v in g Pitm an Arm
cleaned, flushed and
TOOL—J-5504
TOOL—J-6632
LIG H T T R U C K S E R V IC E M ANUAL