GMC 1982 Light Duty Truck, Service Manual

Page: 129 / 1435

AIR CONDITIONING COMPRESSOR OVERHAUL 1D-13
20. Exam ine Internal C ylinder and Shaft Assembly for
any obvious dam age. If Internal Assembly has sustained
m ajor damage, due to loss of refrigerant or oil, it m ay be
necessary to use the Service Internal C ylinder and Shaft
Assem bly rather th an replace individual parts.
A-6 COMPRESSOR INTERNAL
CYLINDER AND SHAFT ASM
D isasse m b ly
Use P arts T ray J 9402 (Fig. ID -33) to retain
com pressor parts during disassembly.
1. Rem ove Internal C ylinder and Shaft Assembly from
com pressor as described in “ A-6 C om pressor Internal
M echanism
(Cylinder and Shaft A sm .)” Rem oval
procedure.
2. Identify by pencil m ark, or some other suitable
m eans, each piston num bering them as 1, 2 and 3 (Fig. 1D-
30).
Fig. 1D-31 Separating A-6 Cylinder Halves
FRONT
CYLINDER
HALF
S U P P O R T
B LO C K j - :
2 0 4 9 5 6
Fig. 1D-30 Numbering A-6 Piston and Cylinder Bores
N um ber the piston bores in the front cylinder h alf in
like m anner, so th a t pistons can be replaced in their original
locations.
3. Separate cylinder halves, using a wood block and
m allet (Fig. ID -31). M ake certain th a t discharge cross-over
tube does not contact axial plate when separating cylinder
halves (a new Service D ischarge Cross-O ver Tube will be
installed later - see Step 5 o f Internal C ylinder and Shaft
Assem bly procedure).
NOTICE:
U N D E R N O C IR C U M S T A N C E S
SH O U L D SH A FT BE S T R U C K A T E IT H E R E N D
in an effort to separate upper and lower cylinder halves
because the shaft and the axial plate could be dam aged.
4. Carefully rem ove the R ear H a lf of the cylinder from
the pistons and set the F ro n t C ylinder Half, w ith the piston,
shaft and axial plate in Com pressing F ixture J 9397.
5. Pull up on com pressor shaft and remove piston
previously identified as No. 1, w ith balls and shoe discs,
from axial plate.
9. Repeat Steps 5 thro u g h 9 for Pistons No. 2 and No.
3.
10. Rem ove rear com bination of th ru st races and th ru st
bearing from shaft. D iscard races and bearing.
11. Rem ove shaft assembly from front cylinder half. If
the D ischarge Cross-O ver Tube rem ained in the front
cylinder half, it m ay be necessary to bend discharge cross­
over tube slightly in ord er to rem ove shaft.
а. Inspect the Teflon piston rings for nicks, cuts or
m etal particles im bedded in exposed ring surface and
replace the piston rings as required if either condition exists.
See “ A-6 Teflon Piston R ing” Replacem ent procedure.
б. Rem ove and discard the piston shoe discs.
7. Rem ove and exam ine piston balls, and if satisfactory
for re-use, place balls in No. 1 com partm ent of P arts T ray
J 9402 (Fig. ID-33).
8. Place piston in No. 1 com partm ent of P arts T ray J
9402, w ith notch in casting web at front end o f piston (Fig.
ID -32) into the dim pled groove of P arts T ray com partm ent.
Fig. 1D-32 Notch Identifying Front End of A-6 Piston
T E F L O N R IN G G R O O V E
N O T w ,,
(P IS T O N F R O N T E
204981