1979 DATSUN 210 cooling

Air

Conditioning

RECEIVER
DRIER

The
receiver

drier
rves
the

pur

pose
of

storing
tl
e

liquid
refrigerant

The
amount

of
the

liquid
refrigerant

flowing
through
the

system
varies

with

the

operating
condition
of
the
air

conditioner
To
be

accurate
the

receiver

drier
stores
excess
amount

of

refrigerant
when
the

heat
load
is

low

ered
It
also
releases

stored

refrigerant

when
additional

cooling
is
needed

thus

maintaining
the

optimum
flow
of

refrigerant
within
the

system

The
receiver

drier
includes
a
strain

er

and
desiccant

They
have
the

job
of

removing
moisture
and

foreign
parti

cles
as
the

refrigerant
circulates
within

the

system

The

pressure
relief
valve
is

installed

beside

the

sight
glass
of
the
receiver

drier

The

purpose
of
the
valve
is

to

release

preSsurized

refrigerant
vapor

into

the

atmosphere
in

the
event
of

excessive

pressure
build

up
in

the

high

pressure
line

The

pressure
relief

valve

opens

automatically
at
a

pressure
of
about

38

kg
cm2
540

psi

EXPANSION
VALVE

The

expansion
valve
restricts
the

flow
of

liquid
refrigerant
as
it

passes

through
it
and

delivers

sprayed
refrig

erant
to
the

evaporator
for

faCilitating

refrigerant

evaporation

The

refrigerani
within

the

sensing

bulb

changes
in

pressure

through
the

super
heat
condit
ion

of

vaporized
re

frigerant
gas
which
comes

out
of

the

evaporator
causing
the

deflection
of

the

diaphragm
The
lift
of
the
ball

valve

attached
to
the

diaphragm
is

changed
by
the
deflection
of

the
dia

phragm
thus

controlling
the

amount

of

refrigerant
passing
the

orifice

AC
4
To

expansion

valve

rl
From
condenser

L
J

C
d

f

@

J

f

J
4
4

1

u

lc

AC167A

1

Pressure
relief
valve

2

Sight
glass

3
Suainer

4
Desiccant

Fig
AC
3
Receiver
Drier

JD

v
t

I

Sensing
bulb

2

Diaphragm

3

Eq
ualizer
line
From
receiver
drier

4

Orifice

5
Valve
ball
To
evaporator

Fig
A
C
4

Expansion
Valve
AC423

COMPRESSOR

OIL
LEVEL
CHECK

The
oil
used
to
lubricate

compres

sor
circulates
into

system
from
the
oil

sump
while

compressor
is

operating

Therefore
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

facio

litates
to

return
oil
to

compressor

1

Operate
compressor
at

engine

idling
speed
I
OOO

rpm
or
below

with

controls
set
for

maximum

cooling

and

high
blower

speed
for
10
to
15

minutes
in
order

to
return
com

pressor

oil
to

compressor

2

Stop
the

engine
and

discharge

refrigerant
of

system
and
then

remove

compressor
from
the

car

3

Remove

compressor
filler

plug

Drain

compressor
oil
from

compres

sor
oil

sump
and
measure
the
amount

AC742

Fig
AC
23
Filler
Plug

4

Compressor
oil
is

satisfactory
if

the

following
amount
of
oil
remains
in

the

compressor

Residual
oil

140
to
220
cc

4
7

to
7
4
US
fl
oz

4
9
to
7
7

Imp
fl
oz
Air

Conditioning

5
Check
the

cleanliness
of
the

oil
If

the
oil
contains

chips
or
other

foreign

material
clean

oil

sump
with
new
oil

6
Discard
the
used
oil
and
fill
with

the
same

amount
of

new
oil
Add

oil
if

found
less

than
above
amount

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

com

pleted
recheck

oil
level
drain
oil

to

correct
level

if
level
is

excessively
high

CAUTION

a
The
oil
should
not
be
transfused

from
a
container
into
another
as

the
failure
will

possibly
cause

moisture
to
mix
with
the
oil

b
The
used
oil
should
not
be
returned

into

a
container

c
The
oil
should
not
be
used
if
its

state
of

preservation
is
not
clear

enough

PERFORMANCE
TEST

The

cooling

per
ormance
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

guiqe

in

checking
for

problems

1
Park
the

car
indoors
or
in
the

shade

2

Open
all
the
windows

of
the
car

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

Gauge

5

Set
air
lever
to

AIC

position

6
Set

temperature
lever
to
maxi

mum
cold

position

7

Set
blower
to
its

highest

speed

8
Start
the

engine
and
hold

engine

speed
at
1
500

rpm

9
After
the
air
conditioner
has
been

operated
for
about
10
minutes
meas

ure

system
pressures
at

high
pressure

discharge
side
and
low

pressure
suc

tion

side

10
Measure
the

temperature
of
dis

AC
17
charge
air
at
the

center
outlet

grille

11
Measure

the

temperature
and

humidity
of
the

evaporator
in
take
air

at

the

recirculating
air
inlet

of
the

evaporator

12
Measure
the

temperature
and

humidity
of
the
ambient
air
at
a

point

I
m
3
3
ft

front
of

condenser

However
a

dry
bulb

and
wet
bulb

must
not
be

placed
in

direct
sunlight

13

Check
for

any
abnormalities
by

comparing
the
test
results

with
stand

ard

pressure
Refer
to

Performance

Chart

Note

a

The

pressure
will

change
in
the

following
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
Refer
to
Trouble

Diagnoses
and
Corrections

REFRIGERANT

LEAKS

If
leaks
are

noticeable
leaky
parts

should
be

repaired
Then
system

should

be
fIlled
with

refrigerant

CAUTION

00

not

operate
compressor
with

refrigerant
level

excessively
low

If
this
caution
is

neglected
a
burnt

compressor
will
result
since

heavy
loss

of

refrigerant
usually
indicates

heavy

loss
of

compressor
liil

I

f

system
has
been

exposed
to

atmosphere
for

an
extended

period
of

time

I
receiver

drier
must
be

replaced

If
leaks
are

slight
and

no
air
is

present

in

system
add

refrigerant
as

necessary

To
detect
leaks

refer
to

Checking

INSTA
L1ATION

InstaU
in
the
reverse

order
of

removal

observing
the

following

I

When

installing
add

required

amount
Of

compressor
oil
Refer
to

Compressor
Oil
Level
Check

2

Apply
a

coat
of
fresh

compressor

oil
to

sealing
surfaces
of

pipe
joints

3
Check

tightening
torque
of
com

pressor
mounting
bolts

compressor

mounting
bracket

mounting
bolts
and

refrigerant
line
See
Figs
AC
27

and

AC
29

4

DO
not
remove
plugs
from

com

pressor
and
flexible
hose
before

connecting
hoses

S
Turn

compressor
several
times

before

installing

6

Adjust
compressor
drive

belt

tension

See

Fig
AC
2S

7
Evacuate

and

recharge
system

Refer
to

General
Service

for

evacuating
system
and

charging
re

frigerant

8
Conduct
leak
test
and
make
sure

that
there
is

no
leak
from
connections

CONDE
NSER

REMOVAL

Disconnect

battery
ground
cable

2

Discharge
system
Refer
to

Gen

eral
Service
for

discharging
system

3
Remove

radiator

grille

4
Remove

center

stay

5
Disconnect

refrigerant
lines
from

condenser

CAUTION

8
Use
wrench
to
fix
union
on
con

denser
and
then
loosen
flare
nut
of

refrigerant
line
with
another

wrench

b

Plug

up
all

openings
in
condenser

and

system
Air

COl1ditioning

6

Remove

mounting
bolts
ihen

remove
condenser

from
car

1a

11

AC384A

Fig
AC
28

Removing
Condenser

INSPECTION

Inspect

joints
of
inlet

and
outlet

pipes
for
cracks
and
scratches

Upon

finding
any

problem
which

may
cause

gas
to
leak

repair
or

replace
con

denser

Condenser
fins
or
air

passages
clog

ged
with
dirt

insects

or
leaves
will

reduce

cooling

effiCiency
of
con

denser
In

such
a
case

clean
fms
or

air

passages
with

compressed
air

CAUTION

Do
not
clean
condenser
with
ste8m

Be

sure
to

use
cold
water
or
com

pressed
air

INSTALLATION

Install
condenser

in
the
reverse

order
of
removal

observing
Ihe
follow

ing

I

When

replacing
condenser
add

same
amount

of
oil
as

was
drained

from

previous
condenser
to
com

pressor

AC

20
2

Keep
piugsin

place
until
im

mediately
before

connecting
work
is

started

3
Refer
to

Refrigerant
Line

for

tightening

torque
on

line
connec

tions

4

Refer
to
General
Service
for

evacuating
and

charging
system

5
Conduct
leak
test
and
make

sure

that
there
is

no
leak
from
connections

RECEIVER

DRIER

REMOVAL
AND

INS

ALLATION

See

Fig
AC
29

Disconnect

battery
ground

2

Discharge
system
Refer

to
Gen

eral
Service
for

discharging
system

3

Disconnect

refrigerant
lines

from

receiver
drier

CAUTION

Plug
all

openings
to

prevent
entrance

of
dirt
and

moisture

4

Remove
receiver

drier

mounting

screws
Remove

receiver
drier

5
Install

receiver
drier
in

the
reverse

order
of
removal
With

plugs
taken
off

immediately
before

connecting
work

is

started
connect
line
and
receiver

drier

Refer
to

Refrigerant
Une

for

tighten

ing

torque

6
Refer

to
General
Service
for

evacuating
and

charging
system

7

Conduct

leak
test
and
make
sure

that

there
is

no
leak
from
connections

INSPECTION

Check

receiver
drier

for
leaks

or

damage
If

necessary
replace

REFRIGERANT
LINES
Air

Conditioning

@

I

J

L

S

r
Z
S
t

@

See

Fig
AC
29
When

replacing

flexible
hose
and
tube
observe
the

following

1

Before

starting
work
be

sure
to

discharge
system

2

When

disconnecting
tubes
be

sure
to

use
two

wrenches
on
both

tubes

3

After
discon

ecting
tubes

plug

all

openings
immediately
to

prevent

entrance
of
dirt
and
moisture

4

Compressed
air
must
never
be

used
to
clean

dirty
line
Clean
with

refrigerant

gas

5
In

connecting
tubes
be
sure
to

apply
compressor
oil
to

seating
surface

and
then

tighten
tubes
to

specified

tightening
torque
See

Fig
AC
30

Be

sure
to
use
two
wrenches
when

tightening
a
flare

nut
of
tube

Coat
seat
surfaces
with
com

pressor
oil
and
then

tighten

AC263

Fig
AC

30
Line
Connection
CD

6
Make
sure

refrigerant
line
is

clamped
securely
Start

engine
and

raise

engine
speed
to

inspect
if
there
is

vibration
or
unusual
noise

7

Conduct
leak
t
st
and
make
su
e

that
there
is
no
leak

from
connections

8
Refer
to

General
Service
for

evacuating
and

charging
system

COOLING
UNIT

REMOVAL

I

Disconnect

battery
ground
cable

2

Discharge

refrigerant
from

sys

tern
Refer
to
General
Service

3
Loosen

flare
nuts
at
each
con

nection
of
inlet

and
outlet

pipes
of

evaporator

AC
21
1

High
pressure
discharge
service

valve

2
Low

pressure
suction
service
valve

3

Compressor

4

Condenser

5
Receiver

drier

6

Cooling
unit

7

Low

pressure
switch

lightening
torque

kg
m
ft
lb

@
4

5
to

5
0
33
to
36

@
3
0
to
3
5
22
to
25

AC385A

Fig
AC
29

Refrigerant
Lines

CAUTION

Immediatelv
plug
up
all

openings

to

prevent
entrance
of

dirt
and

moisture

4
Remove
instrument
under

cover

5
Remove

glove
box

6
Disconnect

wiring
harness

con

nectors
from

compressor
relay
and

thermostat

7
Remove

upper
and
lower

attach

ing
bolts
and

remove

cooling
unit

AC386A

Fig
AC
31
Removing
Cooling
Unit

to

DISASSEMBLY

AND
ASSEMBLY

y
1

7
1
r

II

l

1

Using
a
knife
cut

packings
at

upper
and
lower
case
fit
in

portion

2
Remove

clips
fixing
upper
case
to

lower

case

3

Separate
upper
case
from
lower

case

by

pulling
it

upward

4
Withdraw

evaporator
assembly

out
oflower
case

5
Remove
thermostat
from

upper

case

by
removing

attaching
screWs

CAUTION

Capillary
tube
should
not
be
bent

too

sharply

6
To
assemble
reverse
the

order
of

disassembly
Be

sure
to

join
mating

surfaces
of

packings
at

upper
and

lower
case
fit
in

portion
with
an
adhe

sive

substance

Note

When

installing
thermostat

in

sert

capillary
tube
in
same

place
as

it

was
before
removal
Be
sure
to

insert

capillary
tube
end
about

50

em
19
7

in
from

evaporator
core

INSPECT

ON

In

case

evaporator
core
or

expan

sion

valve
have

gas

leaking
repair
or

replace
it
with

a
new
one
as

necessary

Dirt
and

nicotine
accumulation

on

evaporator
case
will

go
b
d
and
smell
Air

Conditioning

1

Mainrelay

2

Thermostat

3

Upper
case

4

Expansion
valve

5

Evaporator
assembly

6

Lower
case

ID

AC387A

Fig
AC
32

Cooling
Unit

This
means
that

you
have
to

remove

them
from
time

to
time
to
assure

healthful
fresh
air
inside

car

INSTAllATION

Install

evaporator
in
the
reverse

order

of
removal

observing
the
follow

ing

I
When

replacing

evaporator
with

new

one

charge
compressor
with

same
amount
of
new
oil
as
was
drained

before

2

Evaporator
case
should

be
in

stalled
as

close
s

possible
to

heater

unit

3
Refer
to

Fig
AC
29
for

tighten

ing

torque
of
flare
nuts

4
Refer
to
General
Service

for

evacuating
and

charging
system

5
Conduct
leak
test
and
ensu
e

that

there
is

no

gas
leak
from
conne
tion

EXPANSION
VALVE

Expansion
valve
malfunctions
such

as
valve

stuck

open
valve
stuck

close

refrigerant
leakage
and

improper
in

stall
tion

of

sensing
bulb
are
de

scribed

The
first
two
conditions

require

replacement
of

expansion
valve

When
both
water

and

refrigerant

AC

22
are
circulated

in
the

system
frost
cwill

form

near
the
ball
of

expansion
alve

and

block
the
flow
of

refrigerant
In

this
case

however

operation
of
the

valve

can
be
returned
to

normal

by

heating
the
valve

Expansion
valve
is

equipped
with

an

adjusting
screw
However
since

the

screw
is
set

properly
at

the

factory

adjustment
is

unnecessary
If

expan

sion

valve
is

damaged

replace
with

new
one

RIEMOV
L
AND

INSTALlATION

See

Fig
AC
32

Disconnect

baltery
ground
cable

2
Remove
ev

porator
Refer
to

Cooling
Unit
for

removal

3

Remove
heat
insulator

covering

expansion
valve

assembly

4
Remove

clamp
attaching
sensing

bulb

5

Loosen
flare
nuts
and
remove

expansion
valve
from

evaporator
and

inlet

pipe

CAUTION

Plug
all

openings
to

prevent
entrance

of
dirt
and
moisture

6

Installation
is
ill
the
reverse
order

of

removal

THERMOSTAT

REMOVAL
AND

INSTALlATION

See

Fig
AC
32

Remove

cooling
unit

2
Remove

screws

attaching
thenno

stat
and
then

remove
thermostat

CAUTION

Capillary
tube
should
not
be
bent

too

sharply

3
Installation
is
in

the
reverse
order

of
removal

Note
When

installing
thermostat
in

sert

capillary
tube

in
same

place
as

it
was

before
removal

Be
sure
to

insert

capillary
tube
end
about
SO

em

19
7
in
from

evaporator
core

INSPECTION

1
Test

continuity
between
two

switch
terminals

with
test

lamp
or

ohmmerter

Continuity
should
exist

2
With

capillary
tube
end

dipped

into
ice

salt
water
maintained
to
I

oc

300
F
test

continuity
between
two

switch

terminals

Continuity
should

not
exist

3
If

switch
is

found

damaged
re

place

MAIN
RELAY

REMOVAL

AND

INSTALLATION

I
Disconnect

battery
ground
cable

2
Remove

glove
box

3
Disconnect

connector
from
main

relay

4

Remove
screw

retaining
main

relay
to

cooling
unit
then
remove

main

relay

5

Installation
is
in
the
reverse

order

of

removal

INSPECTION

Test

continuity
of

relay
with
ohm

meter
or
test

lamp
In

testing
main

relay
there
must
be

continuity
be

tween

CD
and

CV

When
l2Y

direct

current
is

applied

to

CD

CV
CID

@
normally
close

ti

I

I
6

i

i
f

i

f

Fig
AC
33
Air

Conditioning

HEATER
UNIT

Refer
to
Heater
Unit

Section
BE

WATER
COCK

Refer

to
Water
Cock
Section
BE

BLOWER
MOTOR

Refer
to
Blower

Motor
Section

BE

RESISTOR

Refer

to
Resistor

Section
BE

MICROSWITCH

CV

REMOVAL
AND

INSTALLATION

1
Remove
air

conditioner
control

assembly
Refer

to
Heater
Control

Assembly
Section
BE

2

Remove
screws

attaching
micro

switch
and

then
remove
rnicroswitch

3

Install
rnicroswitch
in
the
reverse

order

of
removal

I

NSPECTI
ON

Make

sure
that

continuity
exists
in

AC
23
AIR

CONDITIONER

CONTROL

Refer
to
Heater
Control

Assembly

for
Air

Conditioner
Section
BE

Note
When

adjusting
AIC
control

cable

and
rod

keep
in
mind
that

OFF

on
front

panel
is
used
as

A

C
for
air

conditioning
sys

tem

FAN

SWITCH

Refer
to

Fan
Switch
Section
BE

1
Microswitch

2
Fan
switch

AC19SA

Fig
AC

34
Microswitch

rnicroswitch
when

its

protruding
part

is

pushed

w

AC199A

Fig
AC

35
Microswitch

Com
pressor
OFF
I

I

Blower
makes

noise
Repair
or
re

place
blower

Bearings
of
com

pressor
clutch
or

idler
pulley

make
noise

Replace

C
l
W
Noisy
Compressor
itself
makes

noise
Repair
or

replace
com

pressor
Belt
is
loose

Adjust
belt

Suction
pressure
is
low

Strainer
in
pipe

Line
Is
restricted

Replace
strainer

Pipe
at
receiver

drier
outlet
has

low
temperature

Receiver
drier
is

restricted
Replace

receiver
drier
I

Fin
and
tube
of

evaporator
or

laminated
evapo

rator
have
some

dents
Replace
or
repair

evaporator

Expansion
valve
is

close
excessively

or
gas
leakage
from

thermo
bulb

Replace
expansion

valve
Compressor
ON
J

I

When
engine

rpm
is
changed

there
are
reso

nant
sounds

Retighten
com

pre
ssor
bracket

bolts
Piping
is
reso

nating
Add

clamp
Insufficient
cooling

Bubbles
in
sight
glaS

Check
refrigeration
line

for
gas
leaks
and
repair

leaks
if
any
Charge
re

frigerant
to
correct

level
In
case
of
too

many
leaks
stop
com

pressor
discharge
the

system
evaCUate
and

recharge
the
system

As
necessary
replace

receiver
drier

Air
in
system
may

cause
bubbles
in
sight

glass

System
pressure
and
temperature
of
discharge
air
llre

abnormal
Refer
to
Performance
Test
Diagnoses

for
detail

Suction
pres

sure
is
high

Expansion

valve
is
open

excessively
Replace
ex

pansion
valve
Discharge
pressure
is

high

Overcharge
of
refrigerant

Discharge
some
of
refrig

erani
to
correct
level

Air
is
mixed
in
Discharge

system
and
replace
drier

Evacuate
and
recharge

system
Condenser
s
fin
is
dented

or
clogged
with
dust

Clean
exterior
surface

with
water
No
bubbles
in

sight
glass

With
manifold
gauge

check
system
pres

sures
Measure
tem

perature
of
discharge

air
Refer
to
Perform

ance
Test
Blower
does
not

rotate
Refei
to
Blower

Motor
Diagnoses

Temperature
of
discharge

air
is
abnormal
but
system

pres5ure
is
normal

Suction
pressure
iJ

high
while
dis

charge
pressure
is

low
Valve
or
gasket

of
compressor
is

damaged
Repair
or
replace

compreuor
Check
air
flow

system
Refer
to
Air

Conditioner
Operation
Chart
Compressor
does
not
run

Refer
to
Com

pressor
Diagnoses

Check
grommets

on
car
s
dash

panel
for
air

leaks
check

other
seal
of

car

PERFORMANCE
TEST

DIAGNOSES

Of
various
conditions
caused
to
the

air

conditioning
system
the

character

istics
revealed
on
manifold

gauge
read

ing
are
shown

in
the

following

Condition
Air

Conditioning

As

to
the
method

of
a

perfonnance

test
refer
to
the
item

of
Perfonnance

Test

Note
In
the

following
table
the

portion
smeared
with
ink

on
each

I
INSUFFICIENT
REFRIGERANT

CHARGE

I

I

@
@

08A

I
ALMOST
NO

REFRIGERANT

i

@

@

AC209A

I
FAULTY
EXPANSION
VALVE

I

I

@
@

AC210A
Insufficient

cooling

Bubbles

appear
in

sight

glass
Probable
cause

Refrigerant
is
small

or

leaking
a
little

No

cooling
action
Serious

refrigerant
leak

In

sight
glass
appear
a

lot

of
bubbles
or

something

like
mist

Slight
cooling

Sweating
or
frosted

expan

sion

valve
inlet

AC37
Expansion
valve
restricts

refrigerant
flow

Expansion
valve
is

clog

ged

Expansion
valve
is
in

operative

Valve
stuck

closed

Thermal
bulb

has

lost

charge
gauge
scale
indicates
a

range
based

on
the

assumption
that
the
air

conditioning
system
is
in

good

order

Corrective
action

I

Leak
test

2

Repair
leak

3

Charge
system

Note
Evacuate

8S
neces

sary
and

recharge

sys

tem

Stop
rompressor
immedi

ately

I

Leak

test

2

Discharge
system

3

Repair
leak
s

4

Replace
receiver
drier

if

necessary

5

Check
oilleve

6
Evacuate
and

recharge

system

If
valve
inlet
reveals
sweat

or
frost

I

Discharge
system

2
Remove

valve
and

clean

it

Replace
it

if
neces

sary

3

Evacuate

system

4

Charge
system

If
valve
does

not

operate

I

Discharge
system

2

Replace
valve

3
Evacuate
and

charge

system