GMC T Series 1994 Repair Manual page 52

NOTICE:
W hen fasteners are rem oved, alw ays reinstall them at the same location from w hich they w ere rem oved. If a
fastener needs to be replaced, use the correct part num ber fastener for that application. If the correct part num ber fastener is not
available, a fastener o f equal size and strength (or stronger) m ay be used. Fasteners that are not reused, and those requiring thread
locking com pound will be called out. The correct torque value must be used when installing fasteners that require it. If the above
conditions are not follow ed, parts or system dam age could result.
G eneral D e s c rip tio n ............................................................. 1D 3-1
V5 C om pressor - Theory o f O p e ra tio n ..................... 1D 3-1
M etric Thread Size Inform ation .................................1D 3-2
U nit R e p a ir ............................................................................. 1D 3-2
M inor V5 C om pressor R epair P ro c e d u re s................ 1D 3-2
i-..
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C om pressor C lutch Plate and
H ub A ssem bly
C om pressor Clutch Rotor and/or B e a r in g ............1D 3-6
C om pressor C lutch Coil .......................................... 1D 3-8
Vehicles using the V5 com pressor (Fig. 1) may have
differences betw een installations in the m ounting brackets,
drive system s, pulleys, connections, and system capacities.
B asic overhaul procedures are sim ilar betw een com pressors
used on different vehicles.
W hen servicing the com pressor, keep dirt and foreign
m aterial from getting on or into the com pressor parts and
system . C lean tools and a clean w ork area are im portant for
p roper service. The com pressor connections and the outside of
the com pressor should be cleaned before any "on-vehicle"
repairs, or before rem oval o f the com pressor. The parts m ust be
kept clean at all tim es and any parts to be reassem bled should
be cleaned w ith Trichloroethane, naphtha, stoddard solvent,
kerosene or equivalent solvent and dried with dry air. Use only
lint free cloths to w ipe parts.
SECTION 1D3
V5 AIR CONDITIONING
COMPRESSOR
CONTENTS
j
1D3— 2
GENERAL DESCRIPTION
M ajor V5 Com pressor R epair P ro c e d u re s .................1D 3-9
Com pressor Shaft Seal R eplacem ent ................... 1D 3-9
Seal Leak Detection ............................................. 1D 3-9
Com pressor Pressure R elief Valve ..................... 1D 3-10
„ „ t c
Com pressor Control S w itc h e s
^ ^ l w l
Com pressor Control Valve A s s e m b ly ..................1D3— 11
Com pressor Leak Testing (E x te rn a l).................... 1D 3-12
Bench-Check P r o c e d u r e ....................................1D 3-12
The operations described below are based on bench
overhaul with the com pressor rem oved from the car, except as
noted. They have been prepared in order o f accessibility o f the
components.
W hen a com pressor is rem oved from the car for
servicing, the am ount o f oil rem aining in the com pressor
should be drained and m easured. This oil should then be
discarded and new 525 viscosity refrigerant oil added to the
compressor.
NOTICE:
Up to 4 oz. of oil can collect in the
crankcase. Therefore, it is im portant w hen replacing a
com pressor that the oil in the old com pressor crankcase
be drained thru the drain plug and m easured (discard
after recording am ount).
All replacem ent com pressors will be shipped from
Harrison with 9 oz. o f oil in the crankcase, the oil m ust be
drained and retained. Then replace the oil in the sam e am ount
as previously recorded from the old com pressor.
V5 COMPRESSOR - THEORY OF
OPERATION
The V5 is a variable displacem ent com pressor that can
match the autom otive air conditioning dem and under all
conditions without cycling. The basic com pressor m echanism
is a variable angle w obble-plate w ith five axially oriented
cylinders. The center o f
displacement is a bellow s actuated control valve located in the
rear head o f the com pressor that senses com pressor suction
pressure.' The w obble-plate
displacement are controlled by the crankcase-suction pressure
differential. W hen the A /C capacity dem and is high, the
, 1TA O
1D3-11
......................................................
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control o f the com pressor
angle and com pressor
,