GMC 1982 Light Duty Truck Service Manual page 126

ID -1 0 AIR CONDITIONING COMPRESSOR OVERHAUL
Fig. 1D-21 A-6 Compressor Shaft and Seal
5. A ttach the ceram ic Seal Seat to the Seal Seat
Rem over and Installer J 23128 and dip the ceram ic Seat in
clean 525 viscosity refrigerant oil to coat the seal face and
outer surface. Carefully install the Seat over the com pressor
shaft end and Seal Protector J 22974 and push the Seat into
place with a rotary m otion. Take care not to dislodge the
seat O-ring. However, be sure Seal Seat makes a good seal
with O-ring. Remove Installer J 23128 and Seal Protector
J 22974 (Fig. I D - 19).
6. Install the new seal seat retainer ring with its flat side
against the Seal Seat, using Snap-Ring Pliers J 5403. See Fig.
ID -18. Use the sleeve from Seal Seat R em over-Installer J
9393 to press in on the seal seat retainer ring so that it snaps
into its groove.
7. Install Com pressor Leak Test Fixture J 9625 (Fig.
ID -22) on rear head of com pressor and connect gage
charging lines or pressurize suction side (low-pressure side)
of com pressor on vehicle w ith R efrigerant-12 vapor to
equalize pressure to the drum pressure. Tem porarily install
the shaft n u t and, with com pressor in horizontal position
and oil sum p down, rotate the com pressor shaft in norm al
direction of rotation several times by hand then leak test the
Seal. Correct any leak found. Remove, discard and later
replace the shaft nut.
8. Remove any excess oil, resulting from installing the
new seal parts, from the shaft and inside the com pressor
neck.
9. Install the new absorbent sleeve by rolling the
m aterial into a cylinder, overlapping the ends, and then
slipping the sleeve into the com pressor neck w ith the overlap
tow ards the top of the compressor. W ith a small screwdriver
' / 3 2 (APPROX.)
STRAIGHT EDGE
"" GAUGE
w ir e
.0 2 6 SHOULD "GO"
.0 7 5 SHOULD"NOT GO*
OR SHOULD '^JUST GO"
SLEEVE
SLEEVE RETAINER
SEAT
RETAINER RING
SEAT
RING
SEAL ASSEMBLY
204983
LEAK TEST
A DAPTER
J-9625
Fig. 1D-22 Leak Testing A-6 Compressor
or sim ilar instrum ent, carefully spread the sleeve until the
ends of the sleeve butt at the top vertical centerline.
10. Position the new m etal sleeve retainer so that its
flange face will be against the front end of the sleeve. The
sleeve from seal seat remove installer tool J 9393 may be
used to install the retainer. Press and tap with a mallet,
setting the retainer and sleeve into place (retainer should be
recessed approxim ately .8mm (1 /3 2 ") from the face of the
com pressor neck). (See Fig. ID -21.)
11. Reinstall the Clutch Plate and H ub assembly as
described in " A-6 Com pressor C lutch Plate and H ub A sm ."
Replacem ent procedure.
Some com pressor shaft seal leaks may be the result of
mispositioning of the axial plate on the com pressor shaft.
The mispositioning o f the axial plate may be caused by
im proper procedures used during pulley and driven plate
removal, pounding, collisions or dropping the compressor.
If the axial plate is mispositioned, the carbon face of the
shaft seal assembly may not contact the seal seat and the
rear thru st races and bearing m ay be damaged.
To check for proper positioning of the axial plate on
the shaft, remove the clutch driven plate and measure the
distance between the front head extension and the flat
shoulder on the shaft as shown in Fig. ID-21. To measure
this distance, use a wire gage (the clearance should be
between .7 and 1.9mm (.026" and .075")). If the shaft has
been pushed back in the axial plate (m easurem ent greater
than 1.9mm (.075")), disassemble the com pressor and
replace the shaft and axial plate assembly rear thrust races
and thrust bearing.
If there also appears to be too m uch or insufficient air
gap between the drive and driven plates, dislocation of the
shaft should be suspected. If the carbon seal is not seating
against the seal seat, it will not be possible to completely
" Evacuate the System" as outlined under discharging,
adding oil, evacuating and
C.C.O.T. A /C systems in the A ir Conditioning section.
12. "A dd Oil, Evacuate and Charge System" (see
discharging, adding oil, evacuating and charging procedures
for C.C.O.T. A /C systems in the air conditioning section).
O IL D R A IN FITTIN G
charging procedures for