Chevrolet 1977 light duty truck, Service Manual

Page: 64 / 861

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CO M PR ESSO R DIAGNOSIS
C O M P R E S S O R N O T E N G A G E D .
C O M P R E S S O R E N G A G E D
B U T N O T O P E R A T IO N A L .
NO V O L T A G E A T
C O M P R E S S O R C O IL.
P R O P E R V O L T A G E
TO
C O M P R E S S O R C O IL.
C LU T C H S L IP P IN G .
B E L T S L IP P IN G .
H IG H T O R Q U E C O M P R E S S O R .
(S E IZ E D )
Retrace electrical circuit back to source of power loss. (See wiring diagrams).
C-K-G MODELS:
Check for defective discharge Pressure Switch by jumping switch connector terminals. If compressor
operates, check for low refrigerant charge. If charge is satisfactory, switch is defective-replace.
C h e ck f o r p ro p e r g ro u n d and
g o o d c le a n e le c tric a l c o n ta c t
at te r m in a ls .
C h e ck f o r p ro p e r a ir gap.
C o rre c t i f necessary.
( . 0 2 2 . 0 5 7 )
C h eck a n d c o rre c t
b e lt te n s io n .
R E F R IG E R A T IO N C H A R G E
IS D E P L E T E D .
S Y S T E M H A S SO M E
R E F R IG E R A N T .
I f c o il is s t ill in o p e ra tiv e ,
re p la c e c o m p re s s o r c o il.
I f p re v io u s s te p d oes n o t
c o r r e c t c lu t c h s lip p a g e ,
re p a ir c o m p re s s o r.
A d d o ne p o u n d
re frig e r a n t.
L e a k te s t c o m p le te
sy s te m b e fo re
re m o v in g c o m p re s s o r.
R e p a ir c o m p re s s o r.
O p e ra te a n d le ak
te s t s y s te m .
8 lo w o u t seal c a v ity
w it h a ir hose and
le a k te s t.
C O M P R E S S O R
T H R O W S O IL .
rl LEAKS REFRIGERANT.
R e p a ir c o m p re s s o r.
D O E S N O T L E A K
W ip e o ff o il - O .K .
C O M P R E S S O R
N O IS Y .
N O TE: A/C system noise is to
be evaluated in the
vehicle with doors and
windows closed and low
blower on.
N O IS Y W H E N C LU T C H
IS NO T E N G A G E D .
C h eck f o r re frig e r a n t
lin e s to u c h in g m e ta l
p a rts . Is o la te a nd
re -e v a lu a te n oise.
N O IS Y O N L Y W H E N
C h e ck a n d a d iu s t
b e lt te n s io n .
C LU T C H IS E N G A G E D .
R e p a ir c o m p re s s o r
if n oise is
o b je c tio n a b le .
R e m o v e c o m p re s s o r b e lt
to d e te rm in e i f noise
s till p ersists.
C h eck f o r in te r fe re n c e
b e tw e e n c o il h o u s in g
a n d p u lle y h u b .
I f in te r fe re n c e
e x is ts , re p a ir
c o m p re s s o r.
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