service DATSUN PICK-UP 1977 Owners Manual

Air
Conditioning

Low

pressure
gauge

Compound
pres
lIrt

gaug
High
rHe
ure

g
Uge

c

7

I

Back
se
ted

Full
counter

J

clockwise

Ji

r

rnF
r

r1
gL

r

W
t

g

2

Connection
to
service
valve

I

Fully
close
both
valves
of
mani

fold

gauge
Connect
high
and
low

pressure
charging
hoses
to
manifold

gauge

2
Remove

caps
from
service
valves

Connect
high
and
low

pressure
charg

ing
hoses
to
service
valves
in

system

The

refrigerant
gas
wili
be

discharged

since
check
valve
is

open
when

pressing
charging
hose
onto

service

valve

3

Next
loosen
the

connection
fit

ting
of

charging
hose
at
manifold

gauge
side
for
2

to
3
seconds
to

purge

any
air

inside

charging
hose

by
the

pressurized
gas
in

system

Disconnedion
from

service
val
v

I

Fully
close
both
valves
of
mani

fold

gauge

2

Disconnect
two

charging
hoses

from
service
valves
At

this
time
the

gas
will
be

discharged
until
check
valve

is
closed
Therefore
disconnect
hose

quickly

Caution
Work
with

fingers
protected

with
cloth

against
frostbite

by
re

fri
l
fant
To
low
side
To
vacuum

pump
OI

To

high
ide

rvicc
valve

refrigerant
can

service
va
lve

HANDLING
SERVICE
VALVE

An
automatic
check
valve
is
built

into

service
valve
When
this
valve

presses
against
the
connection

fitting

that
is
when

charging
hose

is
con

nected
to
service
valve
the
valve
is

open
When

charging
hose
is
discon

nected
the
valve
is
closed
automatical

ly
Always
observe
the

following
usage

precautions

Always
install
valve

cap
after

using
service
valve

When

high
speed
opera
tion
is

per

formed
without
valve

cap
a

negative

pressure
will

gradually
build

up
at

the

low

pressure
side
of

system
and
air

may
be
sucked
in
In
addition
dirt
and

dust

will

easily
enter
the
valve
result

ing
in
foreign
matter

entering
the

system

L

5V

j

Close

AC
l0
Front
seated

Full
clockwise

AC243

Fig
AC
13

Manifold
gauge

2
Check
valve
will
be
half

opened

during
connection
and
disconnection

of

charging
hoses
and

refrigerant
will

be
forcefully

discharged
Therefore

connect
and
disconnect

charging
hoses

quickly
while

pressing
flare
nut

of

charging
hose

against
service

valve

Caution
Work
with

fingers
protected

with
cloth

against
frostbite

by
re

frigerant

3

Since
close
contact
between
the

thread
of
valve

eap
and

the
thread
of

service

valve
will

prevent
gas
leakage

keep
these
sections
clean
and
free
of

scratches
and
damage

4

Since

packing
of

charging
hose

will
be

lost

during
long
use

always

check

packing
prior
to

installing
charg

ing
hose

J

17

t

1
1

t

Cap

2

Service
valve

3

Charging
hose

AC733

Open

Fig
AC
14
Service
oolve

b

r
r

AC734

Fig
A
C

15
Service
value

docK
wise

n

r
Air

Conditioning

HANDLING
CAN
TAP

A

wide

variety
of
can

taps
are

available
The

following
procedures

apply
to

conventional

can

taps

For
the

correct

usage
refer
to

the

manufacturer
s

instructions

Caution
Use

can

tap
of

good
quality

I
Connect

charging
hose
to
the

center
fitting
of
manifold

gauge
At

this
time
confirm
that
both
stems
are

fully
turned
in

front
seated

2
Turn

can

tap
handle

fully
coun

Counterclockwise

s

r

@

A

rn

Purging
air

n

R
I2

AC
terclockwise

so
that
the

needle
is

pulled

up

3
Attach

can

tap
to

refrigerant
can

firmly

4

Turn

can

tap
handle

fully
clock

wise
to

make
a

hole
in

refrigerant

can

5

Turn
the
handle

fully
counter

clockwise
to
raise
the

needle

Refriger

ant

gas
will

flow

up
to
the
center

fitting
of

manifold

gauge

6
Loosen
the

connection
a
t

the

center

fitting
of
manifold

gauge
for
a

few
seconds
to

purge
air

inside

charg

ing
hose
See

Figure
AC
16

1
Can
tap
handle

2

Charging
hose

3
Needle

4

Refrigeran
t
can

AC246

AC247

Fig
AC
16
Can

tap
and

pw
ging
air

q

DISCHARGING
SYSTEM

The

pressurized
refrigerant
gas
Ul

side

system
must
be

discharged
to
a

pressure
approaching
atmospheric

pressure
prior
to

evacuating
refrigerant

inside

system
This

operation
should

be
made
to

permit
safe
re
oval
when

replacing
system
components

I

Close

high
and
low

pressure

valves
of
manifold

gauge
fully

2

Connect
two

charging
hoses
of

manifold

gauge
to

their

respective

service
valves

3

Open
both
manifold

gauge
valves

slightly
and

slowly
discharge
refriger

ant
from

system
See

Figure
AC
17

Note

Do
not
allow

refrigerant
to
rush

out
Otherwise

compressor
oil
will

be

discharged
along
with
re

frigerant

AC735

Fig
AC

17
Discharging

system

Caution
Protect

fingers
with
cloth

against
frostbite

by
refrigerant

when

connecting
the

charging
hose

to

the
service
valve

or

disconnecting

it
therefrom
Air

Conditioning

EVACUATING
SYSTEM

1
Connect

high
and
low

pressure

charging
hoses
of

manifold

gauge
to

their

respective
service

valves
of

sys

tern

and
d

ischarge

refrigerant
from

system
Refer
to

Discharge
System

2

When

refrigerant
has
been

dis

charged
to

a

pressure
approaching
at

mospheric
pressure
connect
center

charging
hose
to
a

vacuum

pump

3
Close
both
valves
of
manifold

gauge
fully
Then
start

vacuum

pump

4

Open
low

pressure
valve
and
suck

old

refrigerant
from

ystem
See

Figure
AC
18

S

When
low

pressure
gauge
reading

has

reached
to

approximately
500

mm

Hg
20
in

Hg
slowly
open
high

pressure
valve

See

Figure
AC
19

6
When

pressure
inside

system
has

dropped
to

710
mm

Hg
28
in

Hg

fully
close
both
of

valves
of
manifold

gauge
and

stop
vacuum

pump
Let

stand
it

for
5

to
10
minutes
in

this

state

and
confirm
that
the

reading

does
not
rise

Notes

a
The
low

pressure
gauge
reads
lower

by
2S

mm

Hg
I

in

Hg

per
a
300

m

1
000
ft
elevation
Perform

evacu

ation

according
to
the

following

table

Elevation

m
ft
Vacuum
of

system

mm

Hg
in

Hg

0

0

300

I
000

600
2
000

900
3

000
710
28

68S
27

660
26

635
25

Note
Values
show

readings
of
the

low

pressure
gauge

AC

12
b
The
rate
of
ascension
of
the
low

pressure
gauge
should
be
less
than

2S
mm
Hg
I

in

Hg
in
five

min

utes

If
the

pressure
rises
or
the

specified

negative

pressure
can
not
be
obtained

there
is
a

leak
in
the

system
In
this

case
immediately
charge

system
with

refrigerant
and

repair
the
leak
de

scribed
in
the

following

I
Confirm
that
both
valves
of

manifold

gauge
are

fully
closed
and

then
disconnect
center

charging
hose

from

vacuum

pump

2
Connect
center
hose
to
can

tap

in

place
of
vacuum

pump
Attach

refrigerant
can
to

can

tap
and

pass

refrigerant
to
manifold

gauge

3

Loosen
the
connection
of
center

fitting
of
manifold

gauge
to

purge
air

from

center
hose

4

Open
low

pressure
valve
of
mani

fold

gauge
and

charge
refrigerant
into

system
After
one
can
about
0
4

kg
I

Ib
of

refrigerant
has
been

charged

into

system
close
low

pressure
valve

5

Check
for

refrigerant
leakage

with
a
leak
detector

Repair
any
leak

ages
found
Refer
to

Checking
for

Leaks
and

Refrigerant
Leaks

6
Confirm
that
both
valves
of

manifold

gauge
are

fully
closed
and

then

change
center

charging
hose
from

can

tap
to
vacuum

pump

7

Open
high
and
low

pressure

valves
and

operate
vacuum

pump
to

suck

refrigerant
from

system
When

the

pressure
in

system
has

dropped
to

710

mm

Hg
28
in

Hg
fully
close

both
valves
of
manifold

gauge

7

The
above

operation
completes

evacuation
of

system
Next

charge

refrigerant
Refer
to

Charging
Refrig

erant

7
After
the

specified
amount
of

refrigerant
has

been

charged
into

sys

tem
close
manifold

gauge
valves
Then

detach

charging
hoses
from
service

valves
of

system
Be
sure
to
install

valve

cap
to

service
valve

8

Confirm
that
there
are

no
leaks
in

system
by

checking
with
a
leak
detec

tor

Refer
to

Checking
for
Leaks

Note

Conducting
a
performance
test

prior
to

removing
manifold

gauge
is

a

good
sen
ice

operation
Refer
to

Performance

Test

CHECKING
FOR

LEAKS

Conduct
a

leak
test
whenever
leak

age
of
refrigerant
is

suspected
and

when

conducting
service

operations

which
are

accompanied
by
disassembly

Dr

loosening
of

connection
fittings
Air

Conditioning

Refrigerant
is
a

colorless
odorless

gas
and

leakage
from

system
is
diffi

cult
to
detect

Accordingly
the
use

of

a

leak
detector
facilitates

check
for

leaks

Two
methods
of

checking
are

available
one

employs
a
halide

leak

detector
which
burns

propane
gas
or

butane

gas
and
the
other

is
an
electric

type
leak

detector

HALIDE
LEAK
DETECTOR

Since
the

propane
leak
detector
and

butane
leak
detector

are
the

same
in

respect
to
their

operation
this

section

describes
the

operation
of
the

propane

leak
detector

The

copper
screen
is
heated

by
the

burning
of

propane
Refrigerant
gas

decomposes
to

color
the
flame
when

it

contacts
the
heated
screen
The

gas
to

be
checked
is
drawn
into

the

sampling

tube

and
sent
out
to
the
burner
A

refrigerant
leak
can

clearly
be
detected

by
variations
in
the
color
of
the
flame

Propane
type

NO
LEAK

SMALL

LEAK

LARGE
LEAK
Greenish

blue

Yellow

Purple
AC010
1

Copper
reaction

plate

2

Flame

adjusting
lines

3

Burner

4

Sampling
tube

5

Strainer

6

Gas
bomb

7
Flame

adjuster

Fig
A
C
25

Checking
for
leak

Butane

type

Pale
blue

Bright
blue

Vivid

green

AC
15
I

Discharge

refrigerant
in

one
or

two
seconds
to
ascertain

that

system

has
a

sufficient

pressure
needed
for

leak
detection

Charge
with
04

kg
I

lb
of

refrigerant
if

necessary

2

Light
leak
detector

Adjust
the

height
of

the
ilame
between

flame

adjusting
lines
at
the

top
and
bottom

of
combustion

tube
A

reaction

plate

will

immediately
become
red

hot

3

Place
the
end

of

sampling
tube

near
the

point
of
the

suspected
leak

in

system

Notes

a
Since

refrigerant
gas
is
heavier
than

air

small
leaks
can
b

easily
detect

ed

by

placing
sampling
tube
direct

ly
below
the
check

point

b
Suitable
ventilation
is

required
If

refrigerant

gas
is

mixed
with
the

surrounding
air
leak
detector
will

always
indicate
a

response
and

detection
of
the
actual
leak
will
be

difficult

c

Never
bold
leak
detector
at
an

angle

Cautions

a
Never

inhale
the
fumes

produced

by
combustion
of

refrigerant
gas

since

they
are
toxic

b
Never
use
halide
torch
in
a

place

where
combustible
or

explosive

gas

is

present

4
The

ilame
will
be
almost

colorless

when
there
is

no

refrigerant
gas
being

burned
When
there
is

a
small

refriger

ant

gas
leak
the
ilame

will
be

green
or

yellowgreen
When

refrigerant

gas
leak

age
is

large
the
ilame
will
be
brilliant

blue
or

purple
Since
the
color
of
the

ilame
will
be

yellow
when
dust
is

being
burned
Or
there
is

aging
scale
on

copper
reaction

plate
always
keep
the

strainer
of

sampling
tube
and
reaction

plate
clean

5

Major
check

points

I
Compressor

Compressor
shaft
seal

rotate
the

compressor
by
hand

Oil
filler

plug

Flexible
hose
connections

Rear
cover
and
side
cover

gaskets

Service
valve

2
Condenser

Condenser

pipe
fitting

Condenser
inlet
and
outlet

pipe

connections

I

3

Piping

Flared
section
of

high
pressure
and

low

pressure
flexible

hose

Pipe
connections

rvice

valve

4

Evaporator
housing

Jnlet
and

outlet

pipe
connections

Expansionvalve

ELECTRIC
LEAK
DETECTOR

for
the

operational
procedures

refer
to

the
instructions
furnished
with

each
electric
leak
detector

Amount

of

refrigerant
Air

Conditioning

REFRIGERANT

LEVEL
CHECK

SIGHT
GLASS

Sight
glass
is

provided
at
the

top
of

receiver

dryer
One

guide
for
whether

there
is

enough
refrigerant
in

system
is

given
by
observing

refrigerant
flow

through
sight
glass
However
this

method

is
unsuitable
for

judging
the

amount
of

refrigerant
The
correct

refrigerant
level

can
be

judged
by

measuring
t
e

system
pressures
in
ac

cordance
with
the

procedures
de

scribed
Performance
Test

I

Start
the

engine
and
hold

engine

speed
at
1
500

rpm

Almost
no

reftigerant

Check
item

Temperature
of

high
pressure

and
low

pressure
pipes
Almost
no
difference

between

high

pressure

and
low

pressure
side

temperature

Bubbles
flow
continu

ousty
Bubbles
will

disappeu
a
nd
some

thing
like
mist

will

now
when

rerrigeran

is

nearly
gone
State
insightglass

A

I
I

AC256

Pressure
of

system
High
pressure
side

is

abnormally
loW

Repa
ir
Stop

compressor
and

conduct
an
overall

check
Insufficient

High
pressure
side
is

warOl
and

low

pressure

side

is

fairly
cold

The
bubbles
are
seen

at
intervals
of
1
2

seconds

A

r

I

AC257

Both

pressures
on

high

and
low

preS
ure
sides

are

slightly
low

Check
for

gas
leakage

repair
as

required
re

plenish
and

charge

system

AC

16
2

Set

temperature
control
lever
to

maximum

position

3

Set
blower
to
maximum

speed

4

Check

sight
gla
after
the

lapse

of
about
five

minutes
Judge
according

to
the

following
table

AC741

Fig
AC
26

Temperature
control
lever

Suitable
Too
much

refri
crant

High
pressure
side
is

hot
and
low

pressure

side
is
cold
High

pressure
side
is

abnormally
hot

Almost

transparent

Bubbles

may
appear

when

engine

speed
is

raised
and
lowered
No
bubbles
can
be

seen

No
clear
difference
exists
between
these
two

conditions

M

II
I

AC258

Both

pressures
on

high

and
low

pressure
sides

are
normal
Both

pressures
on

high

and
low

pressure
sides

are

abnormally
high

Discharge
reft

gerant

from

service
valve
of

10
11

pressure
side

Notes

a
The
bubbles
seen

through
the

sight

glass
are
influenced

by
the
ambient

temperature
Since
the
bubbles
are

hard
to
show

up
in

comparatively

low

temperatures
below
200C
6S0

F
it
is

possible
that

a

slightly

larger
amount
of

refrigerant
would

be
filled
if

supplied
according
to

the

sight
glass
Be

sure
to
recheck

the
amount
when
it

exceeds
200C

680F
In

higher
temperature
the

bubbles
are

easy
to

show

up

b

When
the

screen
in
the

receiver

dryer
is

clogged
the
bubbles
will

appear
even
if
the
amount
of

refrig

erant
is
normal
In
this
case
the

outlet
side

pipe
of
the
receiver

dryer
becomes

considerably
cold

PERFORMANCE
TEST

Check
for
the
amount
of

refrigerant

in
the

system
can
be

made

by
meas

uring

pressure
on

discharge
side

The

correct
amount
of

refrigerant
is

in
the

system
if

pressure
on
the

discharge
side
is
within

the

specified

range
For
details
refer
to

Perform

ance

Test
described
later

Overcharging
will
show

up
in

higher

pressure
on
discharge
side

COMPRESSOR
OIL

LEVEL

CHECK

The
oil

used
to
lubricate

compres

sor
circulates
into

system
from
the

oil

sump
while

c9mpressor
is

operating

The

efore
to

correctly
measure
com

pressor
oil
the

amount
of
oil

flowing

to

system
must
be

considered
If
a

considerable
amount
of

leakage
of

refrigerant
gas
happens
the

leakage
of

compressor
oil
is
also
considered

There

will
be

no

compressor
oil
leak

age
from
a

completely
sealed

system

When

system
operates
under

satisfying

condition
the

compressor
oil
level

check
is

unnecessary

When

checking
the
level

of
com

pressor
oil
or

when

replacing
any

component
part
of
the

system
use
the

following
service

procedure
This

fa

cilitates
to
return
oil
to

compressor

I

Operate
compressor
at

engine

idling
speed
1
000

rpm
or

below

with
controls
set

for
maximum

cooling
Air

Conditionin
j

and

high
blower

speed
for
10
to

15

minutes
in

order
to
return

compressor

oil
to

compressor

2

Stop
the

engine
and

discharge

refrigerant
of

system
and
then

remove

compressor
from

the
vehicle

3
Remove

compressor
fIller

plug

Drain

compressor
oil
from

compres

sor
oil

sump
and

measure
the

amount

4

Compressor
oil
is

satisfactory
if

the

following
amount
of
oil

remains
in

the

compressor

Residual
oil

S5
to
128

gr
3
to
4
oz

5
Check
the
cleanliness
of
the
oil
If

the
oil
contains

chips
or

other

foreign

material
clean
oil

5ump
with
new

oil

6
Discard
the

used
oil
and

fili
with

the
same
amount
of
new
oil
Add

oil
if

found
less
than
above
amount

Fig
AC
27

Filler

plug

If

compressor
is

inoperative
due
to

faulty
compressor
or

heavy
loss
of

refrigerant
remove

compressor
and

repair
as

necessary
Then

pour
oil

up

to
correct
level
and
install
on

engine

After
above

steps
have
been

complet

ed
recheck
oil
level
drain
oil
to

correct
level
if

level
is

excessively
high

PERFORMANCE
TEST

The
cooling

performance
of
the
air

conditioner

changes
considerably
with

changes
in

surrounding
conditions

Testing
must
be

performed
using
the

correct
method
This

test
is
used
to

judge
whether

system
is

operating
cor

rectly
and

can
also
be
used

as
a

guide

in

checking
for

problems

I

Park
the
vehicle
indoors
or
in
the

shade

AC
17
2

Open
all
the
windows
of
the

vehicle
fully
However

close
the

doors

3

Open
the
hood

4

Connect
manifold

gauge
to

high

and
low
side
service
valves
of
the

system
Refer
to

Handling
Manifold

Ga

uge

5

Set
fan
control
lever
to
maxi

mum

6
Set

temperature
control
lever

to

max
cool

position

7
Start
the

engine
and
hold

engine

speed
at
1
500

rpm

S
After
the
air

conditioner
has
been

operated
for
about
10
minutes

measure

system

pressures
at

high
pres

sure

discharge
side
and
low

pressure

suction
side

9
Measure
the

temperature
of
dis

charge
air
at

outlet

grille

10
Measure
the

temperature
of

capin

11
Measure
ambient

temperature

and

humidity
one
meter
3
3
ft

away

from
condenser
front
Be

careful
not

to

expose
dry
buib

and
wet
bulb

to

direct

sunlight

12
Check
for

any
abnormalities

by

comparing
the
test

results
with
stand

ard

pressure
in
Performance

Chart

Notes

a
The

pressure
will

change
in
the

followi

g
manner
with

changes
in

conditions

When

blower

speed
is

low
dis

charge

pressure
will

drop

When
the
relative

humidity
of
in

take
air
is
low

discharge
pressure

will

drop

b

The

temperature
will

change
in
the

following
manner
with

changes
in

conditions

When
the
ambient
air

temperature

is

low
the
outlet
air

temperature

will
become
low

If
the
test
reveals
that
there
is

any

abnormality
in

system
pressure
isolate

the

cause
and

repair
by
reference
to

the
Trouble

Diagnoses
and
Cor

rections

Air

Conditioning

REMOVAL
AND
INSTALLATION

COMPRESSOR

REMOVAL

INSTALLATION

IDLER
PULLEY

FAN
BELT

TENSION
ADJUSTMENT

REMOVAL
AND
INSTALLATION

INSPECTION

COOLING
UNIT

REMOVAL
AND
INSTALLATION

DISASSEMBLY
AND
ASSEMBLY

INSPECTION

RECEIVER
DRYER
AND
PIPING

COMPRESSOR

REMOVAL

I
Remove

battery

2

Disconnect

compressor
lead
wire

at
connector

3
Loosen
idler

pulley
lock

nut
then

adjusting
bolt
Remove

compressor

drive
belt

from

compressor
pulley

AC477

Fig
AC
28

Removing
drive
belt

4

Discharge
system
Refer
to
Dis

charging
System
under
General
Service

section
CONTENTS

AC
25

AC25

AC26

AC
27

AC
27

AC27

AC
27

AC27

AC
27

AC
2B

AC
29

AC
29
REMOVAL

AND
INSTALLATION

INSPECTION

WIRING

HARNESS
AND

COMPONENTS

WIRING
DIAGRAM

MAINTENANCE

MAIN
RELAY

COMPRESSOR

RELAY

FAN
SWITCH

RESISTOR
FOR
FAN
SWITCH

THERMO
SWITCH

F
I

C
D
SOLENOID
VALVE
AC29

AC29

AC30

AC30

AC31

AC31

AC31

AC31

AC32

AC32

AC
32

5
Remove
flexible
hose

fixing
plate

and
disconnect
low
and

high
pressure

flexible
hoses
from

compressor

Notes

a
Use
two

wrenches
when
disconnect

ing
pipe

joints

b

Plug
flexible
hose
and

compressor

joint
openings
immediately
after

disconnection
to

prevent
entry
of

dust
moisture
laden
air
etc

Fig
AC
29

Disconnecting
ftexible

hoses

from
compressor

6
Remove

bolts

securing
fuel
tube

to

compressor
attachment

AC
25
Y
1

L

AC744

7
Remove
four
bolts

securing
com

pressor
to
its
bracket

Compressor
and

attachment

can
now
be
detached
as
an

assembly

Notes

a
There
are
a

total
of
four
bolts
two

on

upper
side
of
bracket
and
two

on
lower
side
of

compreSsor

Loosen

upper
bolts
and
remove

lower
bolts
When

removing
upper

bolts

securely
hold

compressor

with
one
hand

b
When

installing
temporarily
tighten

upper
bolts
then

tighten
lower

bolts

I

o

Fig
AC
37

Disconnectirt
connector
3

DISASSEMBLY
AND
ASSEMBLY

I
Remove
bracket
and
lead
wire

connector
main

relay
thermo
switch

resistor

motor
etc
from

cooling

unit

2

Remove
five
screws
and
duct

3
Remove
main

relay

4

Remove
thermo
switch

5

Remove
three
screws
and
five

springs
securing

upper
case
lower
case

and

rear
bracket

6
Unfasten

fittings
securing
inlet

and
outlet

pipes
Air

Conditioning

11
To
install

cooling
unit
reverse

the
order
of
removal

Notes

a

Apply
a
coat
of

fresh

compressor

oil
to

sealing
surfaces
when
COD

necting
pipe
joints

b
Use
two
wrenches
when
connecting

cooling
pipes

c
Evacuate
cooling

system
then
re

chaJge
with

refrigerant

Refer
fo

Evacuating
and

Charging

System
under
General
Service
see

tion

9

7

Upper
and
lower
cases
can
now

be

separated

8
Remove
motor
and
fan
as
an

assembly
Also
remove

evaporator

9
Peel
heat

insulating
tape
from

ex

pansion
valve
and
unfasten

clip
secur

ing
expansion
valve

capillary
tube
to

pipe

Remove

expansion
valve
from

evap

orator

10
To
install
reverse
the
order
of

removal

AG
28
d
Check

refrigerant
leakage
if
neces

sary
repair
Refer
to

Checking
for

Leaks
under
General
Service
sec

tion

Tightening
torque

Copper
tube

joint
nut

High

pressure
side
3

8
in

2
5
to
3
5

kg
m

18
to
25
ft
lb

Low

pressure
side
I

2
in

2
5
to
4
0

kg
m

18
to
29
ft
lb

00

L

1

Motor

2

Fan

3
Lower
case

4

Cooler
duct

5

Evaporator

6

Expansion
valve

7

Upper
case

8
Resistor

9
Main

relay

10
Thermo
switch

11
Cable
c

mp

12
Cable

3
Harness

AC725

Fig
A
C
38

Disassembling
cooling
unit

Expansion
valve

tightening

torque

5

kg
m
36
ft
Ib

Notes

a
When

installing
expansion
valve
on

evaporator
make
sure
that

temper

ature
oensing

capillary
tube
is
in
its

proper
position
on
outlet
side

b

Apply
a
coat
of
fresh

compressor

oil
to

sealing
surfaces
of

pipes

INSPECTION

Evaporator

Check

evaporator
for

leakage
or

damage
If

damaged
replace

Expansion
valve

Check

expansion
valve
for

leakage

or

clogging
If

clogged
clean
filter
in

expansion
valve
If

damaged

replace

RECEIVER
DRYER

AND

PIPING

REMOVAL
AND

INSTAUATION

Receiver
dryer

I
Disconnect

battery
ground
cable

2

Discharge
system
Refer
to

Dis

charging
System
under
General
Service

section

3

Disconnect

compressor
lead
wire

at

connector

4

Disconnect

cooling
pipes
at

joints

Acno

Fig
AC
39

Diaconnecting
coo

ing

pipes

Notes

a

Plug
all

piping

joints
immediately

after

pipe
disconnection
to

prevent

entry
of
dust
or
moisture
laden
air

into

receiver

dryer
or
air
aJOdi

tioning
system

b
Use

two
wrenches
when
dIsconnect

ing
cooling
pipes

5

Remove
four
screws

securing

receiver

dryer
bracket

to
vehicle

body

and
detach

compressor
relay
and

pres

sure
switch
as
an

assembly

6
To

install
receiver

dryer
and

piping
reverse
the
order
of
removal
Air

Conditioning

Notes

a

Apply
a
coat
of
fresh

compressor

oil
to

sealing
surfaces
when
con

necting
cooling

pipes

b
Use
two
wrenches
when

connecting

cooling
pipes

c

Evacuate

cooling
system
then
re

charge
with

refrigerant

Refer
to

Evacuating
and

Checking

System
under
General
Service

sec

tion

d
Check

refrigerant

leakage
if
neces

sary
repair

Refer
to

Evacuating
and

Charging

System
under

General
Service
See

tion

Condenser

Disconnect

battery

ground
cable

2

Discharge

system
Refer

to
Dis

charging
System
under
General

Service

section

3
Drain

engine
coolant

4

Remove
radiator

grille

5

Remove

radiator

shroud
and

radiator

On
automatic
transmission

models

disconnect
both

torque
converter
oil

hoses

Note

While

cooling
water
is
hot

take

precautions

against
scalding

6
Disconnect
two

pipes
from

con

denser
remove
two

screws

securing

condenser

Condenser

can
now
be

removed

AC485

Fig
AC

40

Removing
conden
er

Notes

a
Use

two
wrenches
when
disconnect

ing
pipe

joints

b

Plug
openings
immediately
after

disconnecting
pipes

7

To
install

reverse
the
order
of

removal

AC

29
Tightening
torque

Flare
nut
for

copper
tube

from

compressor

2
5
to
4
0

kg
m

i8
to
29
ft
Ib

Flare
nut

for

copper
tube

to
receiver

dryer

2
5

to
3
5

kg
m

i8
to
25
ft
lb

Notes

a
When

disconnecting
and

connecting

cooler

pipes
be
sure
to

use
two

wrenches

b

Apply
a
coat
of
fresh

compressor

oil
to

sealing
surfaces
when

con

necting
cooler

pipes

c

To

prevent

possibility
of

explosion

due
to

high

pressure
within

cooling

system
do

not
clean
condenser

with
steam

Always
use
cold
water

or

cold

compressed
air

d
Evacuate

cooling
system
then
re

charge
with

refrigerant

Refer
to

Evacuating
and

Charging

System
under
General

Service
sec

tion

e
Check

refrigerant
leakage
if
neces

sary
repair
Refer
to

Checking
for

Leaks
under
General
Service

sec

tion

INSPECTION

RecelYer

dryer

Check
for

refrigerant
leakage
or

damage

Check
for

proper
connection
of

two

lead
wires

running
to

pressure

switch

If

any
component

part
is
found

damaged
replace
receiver

dryer
and

pressure
switch
as

an

assembly

Condenser

I

Check

inlet
and
outlet

pipe
joints

and

sealing
surfaces
for

damage
Re

place
parts
if

damaged
or

leaky

2

Clogged
condenser
fins
or

air

pas

sages
may
reduce

cooling
efficiency
of

condenser
Clean
these

areas
with

dry

compressed
air

Piping

Check

piping
for

leakage
If

leakage

occurs
at
connections

retighten

connecting
nuts

Replace
if

leakage

persists

MAINTENANCE

Replace
any
wiring
harness
which
is

cracked
deteriorated
or

poorly
in

sulated

Always
replace
wire
with
those
of

the

same
diameter
Do

not
use
wire
of

smaller
diameter

Where

necessary
securely
retain

wire
harnesses
with

clips
or

tapes
so

that

they
will
not
be

frayed
or
worn

by
vibration

Notes

a

Repair
or

replace
any
electrical

part

which
is

questionable
or
likely
to

cause
a
short
circuit

When
disconnecting
battery
cables

always
disconnect

ground
cable
be

fore

positive
cable
Clean
battery

and
terminals
before

connecting

cables
then
connect

positive
cable

and

ground
cable
in

that
order

Apply
a
coat
of

grease
to
terminals

to

prevent
rust
formation

b
Do
not

attempt
to
conduct
a
con

tinuity
test
with
a

screwdriver
or

service
tools

always
use
test
lead

wires

c
Do
not

ground
terminals
when

circuits
are

open
or
unloaded

always
use

a
test

lamp
12V
3W

or
circuit
tester
as
a

load

MAIN
RELAY

Removal
and
Installation

The
main

relay
is
attached
to
the

cooling
unit

I

Disconnect

battery

ground
cable

2

Disconnect
main

relay
lead
wires

at
connector

3

Remove

cooling
unit

assembly

Refer
to
Removal
and
Installation

under

Cooling
Unit

4
Remove
the
screw

securing
main

relay
to

cooling
unit

and
detach
main

relay

5

To
install
main

relay
reverse
the

order

of
removal

Inspection

To

check

continuity
in

relay

circuit
use
a

test

lamp
or
an
ohm

meter

Continuity
between

points
3

and
4
should
exist
Air

Conditioning

When
a
12

volt
d
c
is

applied
across

points
3
and
4

continuity
between

points
I
and
2

should
also
exist

CD

00

COMPRESSOR
RELAY

Removal
and
installation

Disconnect

compressor
relay
lead

wires

at
connector

2
Remove

two
screws
securing
com

pressor
relay
to
receiver

dryer
and

detach

compressor
relay

3
To
install

compressor
relay
reo

verse
the
order
of
removal
@

I
ul

CDe
JOO

ID
IDe

@e

L

AC465

Fig
AC
42
Main

relay

Inspection

Using
a
test

lamp
or

an
ohmmeter

make

sure
that

compressor
relay
con

tacts

open
and

close
con

tinuously

Continuity
always
exists
between

points
3
and
4
When

current
flows

through

points
3

and
4

points
1

and
2
close
This

causes
current
to

flow

through
1
and
2

FAN
SWITCH

Removal
and
installation

1
Disconnect

battery
ground
cable

2
Remove

screws

securing
console

box
Withdraw
console
box
forward

and
disconnect
lead
wire
connector

3
Detach
switch
knob

4
From
rear
side
of
console
box

remove
screws

securing
switch
and

remove
switch

5
To
install
fan
switch
reverse
the

order
of
removal

AC
31
i
t
v

J

AC489

Fig
A

C
43
Compressor
relay

AC771

Fif
AC

44
Removing
fan
switch