Buick LeSabre 1965 Service Manual page 785

1 1 - 5 2 OPTIONAL HEATER-AIR CONDITIONER SYSTEM
ACCESSORIES
c. Oil Pump
An oil pump mounted at the rear
of the compressor picks up oil
from the bottom of the compres-
sor and pumps it to the internal
parts. The inner gear has a "D"
shaped hole in the center which
fits over a matching "D" flat
on the rear of the main shaft. The
outer driven gear has internal
gear teeth which mesh with the
external teeth on the inner (drive)
gear.
d. Main Shaft
The compressor main shaft is
driven by the pulley when the
magnetic clutch is energized. The
shaft extends through the com-
pressor front head, to the com-
pressor rear head and drives the
oil pump in the rear head. The
shaft is supported by a needle
roller bearing located in the front
half of the cylinder and a similar
needle roller bearing in the rear
half of the cylinder.
A 3/16 inch diameter oil passage
extends from the rear oil pump
cavity to the shaft seal cavity.
Four 5/64 inch diameter holes
are drilled at 90 degrees to the
main oil passage. These drilled
passages direct oil, under pump
pressure, to the shaft seal sur-
faces, thrust bearings, and shaft
cylinder bearings.
11-63.
See Figure
Figure 11-62—Suction Valve Reed
Discs and Discharge
Valve Plates
e. Thrust Bearings and Races
Two needle thrust bearings are
seated around the shaft and are
located near the center of the
compressor. These bearings have
rollers placed radially in their
housing. Each bearing is "sand-
witched" between two steel thrust
races, and this combination of
three pieces is placed between
the shoulders of the swash plate
and the shoulders of the cylinder
hubs on the front and rear halves
of the cylinder. See Figure 11-64.
The front end combination, con-
sisting of a needle bearing with a
selected thrust race on each side,
provides the proper head clear-
ance below the top of cylinder
and the underside of the suction
and discharge valve plates. See
Figure 11-65.
The rear end combination, con-
sisting of a needle bearing with a
selected thrust race on each side,
obtains a .005 to .0015 running
clearance between the hub sur-
faces of the swash plate and the
front and r e a r hubs of the
cylinder.
f. Cylinder Block and Piston
The cylinder assembly consists
of two halves, front and rear.
Alignment and register of the two
halves are maintained by two lo-
cator (roll) pins. Cylinder block
assemblies are only serviced in
matched sets (front and rear
halves).
The double end pistons are made
of cast aluminum. Each piston
has a notch cast in one end for
identification p u r p o s e s . This
notched end of the piston is to be
positioned toward the front end
(pulley end) of the compressor.
Both ends of the pistons have a
groove to receive a piston ring.
Two oil return holes are drilled
behind the ring groove and extend
toward the center area of the
piston to allow oil to drain to the
compressor oil sump. The piston
rings have an oil scraper groove
at one edge to wipe any excess
oil back into the oil sump (reser-
voir) through the oil return holes.
A spherical cavity is located in
the inside center on each side of
the pistons to receive the drive
balls (see Figure 11-64).
g. Shoe Discs
Shoe discs are made of bronze
and one side is a flat surface
which contacts the surface of the
swash plate. The opposite side
has a coined concave surface into
which is assembled the drive
ball.
These shoes are provided in .005
inch increments and ten sizes
are available for servicing these
parts. Also, a basic zero shoe
size is a v a i l a b l e for u s e
during compressor rebuilding
operations.
All service shoes will be marked
with the shoe size, which will
also correspond to the last three
digits of the part number.
SHAFT
OIL INLET
TUBE
OIL
RESERVOIR
Figure 11-63—Oil Flow in Compressor