GMC 1976 ZEO 6083 Maintenance Manual page 211

AIR RESERVOIR INSTALLATION
(FIGURE 9)
1 . Install mounting brackets, safety valve, and
Schrader valve on air reservoir body . Install drain
cock if used .
2 . Install pressure switch to air line at front of air
reservoir .
3 . Install air reservoir in vehicle with two bolts
and nuts through the front mounting bracket and
two nuts and bolts through the rear mounting
bracket.
4. Connect two air lines to side of reservoir.
5 . Connect pressure switch wiring, and install
switch cover.
HEIGHT CONTROL VALVE
INSTALLATION
Before installing height control valve assembly,
see that air line fittings are clean and undamaged.
NOTE :
DO NOT USE SEALING COM-
POUND ON THREADS. Sealer is unneces-
sary, and if used, may cause valves to stick.
Absolute cleanliness is essential when installing
height control valves . Dirt and sealing com-
pound must be kept out of valves . Even minute
particles of foreign matter may become lodged in
valve cores or flapper valves and may seriously
affect operation of suspension system .
1 . Position height control valve at mounting
studs on wheelwell. Attach with two nuts and tighten
to 80-120 in . lbs . torque .
2. Connect air supply line to intake adapter, con-
nect bellows air line to outlet adapter. Tighten air
line connector nuts firmly .
3. Connect height control valve overtravel lever
to valve link and tighten to 60-90 ft . lbs. Build up air
pressure in system and test for leaks. Check ride
height dimension and adjust if necessary as described
later in this section.
AIR BELLOWS INSTALLATION
1 . Place air bellows piston on floor, cone section
pointing up . Place air bellows in piston, with open
end pointing up .
REAR SUSPENSION 4- 2 7
Figure 57-Applying Shop Air
to
Air Bellows
2 . Referring to Figure 57, apply shop air to bel-
lows while pushing down on bellows, release air pres-
sure . The bellows will fold over the piston .
3 . Place second piston over top of bellows and
apply shop air again as shown in Figure 58 . Push
down on bellows and release air pressure . Bellows
will fold over piston . Completed bellows assembly
should appear as shown in Figure 39 .
4. Raise rear wheels to bring top of control arms
close together . Block control arm is shown in Figure
70 . Place air bellows in position . Install star washers
and lock nuts . Torque lock nuts to 50-60 ft .-lbs.
5 . Connect air line and move height control valve
arm up to apply air to bag.
6. Connect leveling valve link . Lower vehicle to
ground and allow leveling valve to bring it to proper
ride height .
CONTROL ARM INSTALLATION
1. With the aid of hammer as shown in Figure 60,
tap two back hat section spacers in mounting bracket
to provide more room for control arms in bracket.