GMC 1976 ZEO 6083 Maintenance Manual page 112

Figure 98-Installing Front Discharge Valve Plate
7 . Determine
exact
position of front head casting
in relation to dowel pins on internal mechanism .
Mark position of dowel pins on sides of front head
assembly and on sides of internal mechanism with a
grease pencil. Carefully lower front head casting into
position (figure 100),
making certain that sealing area
around center bore of head assembly does not contact shaft
as head assembly is lowered . Do not rotate head assem-
bly to line up with dowel pins, as the sealing areas
would contact reed retainers.
8 . Generously lubricate new O-ring and angled
groove at lower edge of front head casting with 525
viscosity refrigerant oil and install new O-ring into
groove (figure 101) .
9. Coat inside machined surfaces of compressor
Rear Discharge
Front Discharge
Valve Plate
Valve Plate
Figure 99-Front and Rear Discharge Valve Plate
AIR CONDITIONING SYSTEM 1- 9 5
Figure 100-Installing Front .Head Casting
shell with 525 viscosity refrigerant oil and position
shell on internal mechanism, resting on O-ring seal .
10 . Using flat-side of a small screwdriver, gently
position O-ring in a round circumference of internal
mechanism until compressor shell slides down over
internal mechanism. As shell slides down, line up oil
sump with oil intake tube hole (figure 102) .
11 . Holding Support Block, invert assembly and
place back into Holding Fixture with front end of
shaft down . Remove Support Block.
12 . Install new dowel pins in rear cylinder half,
if previously removed.
Figure 101-Front Head O-Ring Installed