1977 DATSUN PICK-UP oil

CD
m
Cl
@
D
@

I

j

1
To
instrument
harness
IS
To
battery
30
To
check
connector

2
To
full
transistor
amplifier
16
To
fusible
link
3t
To
headlamp
L
U
type
2

California
models
only
17
To
engine
harness
No
2
32
To
sido
marker
lamp
L
B

3
To
hood
switch
18
To
alternator
33
To
front
combination
lamp
L
H

4
To
engine
compartment
lamp
1
9
To
front
combination
lamp
R
n
34
To
horn
Low

ll
l
S
To
washer
motor
20
To
headlamp
R
H
type
2
3S
To
horn
High

l
l
0
6
To
auto
choke
heater
relay
1
To
side
marker
lamp
R
n
36
To
B
C
D
D
cut
olenoid
California
models

7
To
detector
dri
e
counter
22
To
headlamp
R
B
type
1
only

Non
Califunia
model
except
for
Canada
23
To
ground
37
To
block
tcrminal
distributor
California

8
To
ignition
relay
California
models
only
i4
To
thermal
transmitter
models
only

9
To
floor
sensor
relay
California
modeb
only
is
To
distributor
Non
California
models
only
38
To
ignition
coil
Non
California
models
only

n
10
To
inhibitor
relay
A
T
only
26
To
8
C
D
D
cut
solenoid
Non
California
39
To
condenser

t
II
To
head
lamp
relay
models
only
40
To
ignition
coil
and
resistor
@

12
To
horn
relay
27
To
fuel
cut
solenoid
California
models
only

OJ
v

m
13
To
voltage
regulator
28
To
auto
choke
heater

g
e
14
To
cooler
cable
29
To
headlamp
L
R
type
1

OJ
to

o
Q
m
r0

C
1
i

Ql
CIl
Il
l
3

m
W

D
to
l
l
0
c
l
l
s
Q
3
For
Automatic

Transmission
LB

B

For
Manual
Transmission

m
For
Automatic
Transmission

COLOR
CODE

B
Black

BI
Brown

G
Green

L
Blue

Lg
Light
green

R
Red

W
White

Y
Yellow

BW
Black
with
white
stripe

LgR
Light
green
with
red
stripe
BY
RB
RB

B
WB
RB

YB
2
RB
I
B

1

BW
r
BY

LB

For
Automatic

Transmission
to

o
c
m
r0

O
O
Dl

For
Manual

Transmission
@
CJ
lti
3

RB
fB

BY
YB
RB@RB
YB
BY

1
To
kickdown
solenoid

fOT
Automatic
Transmission

2
To
reverse
switch

for
Manual
Tranmission

3
To
inhibitor
switch

for
Automatic
Transmission

4
To
oil
pressure
switch

5
To
starter
motor

6
To
engine
room
harness

for
Manual
Transmission

7
To
engine
room
harness

for
Automatic
Transmission

@
BG
B
LW
LW
B
L

AL
l
J
YA

CD
m
LW
4
ft
GL

LR
t4
B
t
R

LG
4D
It
GW

BW
GW

L

@

ii
b
l
l
l
lD
m

en
lD
A
A
G
Ri
G
L

Non
California

except
Canada
I

G
GR
13
L
R
j

M
T
only
GL

A
T
only
To
engine

compartment
harness

Non
california
except
Canada
G
r

wRfl
Lt
IIY

LIB
l
ll
RY
R
oIll
CD

o
c
m
o
O
II
fJl
1
3

REFRIGERAi
H
R
12

COMPRESSOR
OIL

MAINTENANCE

PERIODIC
MAINTENANCE
AND

SEASON
IN

INSPECTION

GENERAL
SERVICE
INSTRUCTION

SAFETY

PRECAUTIONS

EV

ACUA
TlNG
AND

CHARGING
SYSTEM

HANDLING

MANIFOLD
GAUGE

HANDLING
SERVICE
VALVE

HANDLING
CAN
TAP

DISCHARGING
SYSTEM

REFRIGERANT
R
12

The

refrigerant
used
in
the
air

conditioner
is

generally
called
Re

frigerant
12

R
12
No
other

refrig

erant
than
the

above

refrigerant
should

be
used

This

refrigerant
is

usually
available

in
a
small
can
or
a

cylinder
In

either

case
it

is

liquefied
under

high
pressure

in
the
container

Refrigerant

evaporates
easily
has
a

low

evaporation
point
and
moreover

since
the
latent

heat
of
the

refrigerant

is

large
it

can
abSorb

a

large
amount

of
heat

wh

err
e

vaporating
Extreme

care
must
be
exercised
when

handling

the

refrigerant

COMPRESSOR
OIL

The
SUNISO
5GS
or
SUNISO

351

should
be
used
as

refrigeration

lubricant

Mixing
of
the

two
is

allowable

The

refrigeration
lubricant
should

be
used
to
assure
the
successful
com

pressor
operation
Use
of
oils
other

than
recommended
or

mixing
of
the

oil

with
other
oils
would
cause

chemical
reaction

or
lead
to
lowered

viscosity
or
deficient
lubrication

The
oil

absorbs
moisture
as
it

con

tacts

the
air
This

points
out
the
need

for

care
not
to

expose
it

to
atmos

phere
for
an

extended

period
of
time
Air

Conditioning

GENERAL
SERVICE

CONTENTS

EVACUATING
SYSTEM

CHARGING
REFRIGERANT

CHECKING
FOR
LEAKS

HALIDE
LEAK

DETECTOR

ELECTRIC
LEAK

DETECTOR

REFRIGERANT
LEVEL
CHECK

SIGHT

GLASS

PERFORMANCE
TEST

COMPRESSOR
OIL
LEVEL
CHECK

PERFORMANCE
TEST

REFRIGERANT

LEAKS
AC
8

AC

8

AC
8

AC
8

AC
8

AC
9

AC
9

AC
9

AC10

AC

11

AC
12

MAINTENANCE

PERIODIC
MAINTENANCE

AND

SEASON
IN

INSPECTION

Both

periodic
maintenance
and

season
in

inspection
are

most
essential

to
enable
the
air

conditioner
to

give

full

performance

Perform
the

following
checks

Start

engine
and

check

refrigerant

level

through
sight
glass
on

receiver

dryer
For

details
refer
to

relative

topics
under

Refrigerant
Level

Check

2
Check
the
entire

sysiein
for

sign

of

refrigerant
leaks

Refer
to
relative

topics
under

Checking
for

Leaks

and

Refrigerant
Leaks

If

any
trace
of
oil
is

noted
at

and

around
connection

fittings
it
is
a

sure

indication

that

refrigerant
is

leaking

This
condition

can
be
corrected

easily

by
retightening
the

joints
If

any
joint

on
line

is

suspected
of
small
amount
of

leakage
use
a
leak

detector
to

locate

leaking
points

3
Check

compressor
drive
belts

for

proper
deflection

Season
off

Observe
the

following
maintenance

tips
to
allow

the
air

conditioner

to

operate

normally
in

the
next

season

I

Keep
the
entire

system
free
from

AC
8
AC12

AC

13

AC15

AC15

AC16

AC

16

AC16

AC
17

AC17

AC
17

AC18

refrigerant
leakage
by

periodically

checking
for

refrigerant
gas
leak

even

out
of
season

2

Turn
the

compressor
for
10

minutes

at
least
once
a
month

by

running
the

engine
at
1

500

rpm

c
ENERAL
SERVICE

INSTRUCTION

The

servicing
of
the
air
conditioner

should
be
carried
out

only
by
well

trained
servicemen
This

chapter
de

scribes
essential

points
of

servicing

Jf

a

Jarge
amount
of

dirt
and
sand

enter

the

system
they
will
be

carried
with

refrigerant
and

may

clog
the

system
or
scratch

rotating

parts
This

points
out
the
need
for

care
in

servicing
the

system
That

is

disconnecting

joints
should
be

carried
out

in
a
dean

place

Water
should
not
be
allowed
to

get

inside
the

system
The

refrigerant

does
not

readily
mix

with
water

However
the

presence
of
even
a

minute

amount
of

water
will
cause

a
chemical
reaction

at

high
tem

perature
which
will
in

turn

produce

hydrochloric
acid

HCl
Since

hydrochloric
acid
is

highly
corro

sive
to
metals
the
aluminum
and

copper
piping
etc
will
become

corroded
and
the

refrigeration

system
will
become

clogged

Water
in
the

system
will

ice
the

orifice
when
the

high
pressure
re

frigerant
is

changed
to
low

pressure

refrigerant
by

expansion
valve
etc

and
will
obstruct
the

refrigerant

flow

The

following
items

are

general

instructions
to
be

closely
observed
in

servicing
the

system

I
When
a

system
line
is

discon

nected

plug
the

opening
immediately

This
is

especially
necessary
to

prevent

moisture

condensation
from

forming

in
the
line
and
to

keep
out
dirt
and

dust
It
is
also

necessary
to

keep
the

line
at
and
above

surrounding
air

temperatures
at
all

times
When

con

necting
system
lines
do

not

attempt

to
remove
the

plug
from
the

opening

until

ready
for
immediate
use

2

Always
keep
the

working
place

clean
and

dry
and
free
from
dirt
and

dust

Wipe
water
off
with
a
clean

cloth

3
Have
all

necessary
tools
in

pre

paration
beforehand

and
have

tools

clean
and

dry

4
The

compressor
oil
will

easily

absorb
moisture
when

exposed
to
air

Immediateiy
close
the

opening
of
the

container
after
use
It
is
also

necessary

to
observe
the

following
notes

Notes

a
The
oil
should
not
be
transfused

from
a
container
into

another
as

the
failure

will

possibly
cause
mois

ture
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

5
When

connecting
or

disconnect

ing
pipes
from
the

refrigeration
sys

tem
use
two

wrenches
One
wrench
is

used
for

holding
the

fixing
nut

in

place

while
the

other
for

turning
the

mating

flare

nut
Failure
to
do

so

may
result

in
a

twisted
tube
or

may
damage

connection

6
Also
use
care
not
to

give
scratches

to
the

seating
surface
at
connections

A

small
scratch
on

the

seating
surface
Air

Conditioning

may
be
the
cause
of

gas
leakage

Before

connecting
pipes
be
sure
to

give
coating
of

compressor
oil
to
the

sea

ting
surfaces

SAFETY

PRECAUTIONS

I

Since
direct

contact
of
the

liquid

refrigerant
with

your
skin
will
cause

frostbite

always
be
careful

when

handling
the

refrigerant
Wear

gloves

or

wrap
a

piece
of
cloth
around
service

valve

to

protect
your
fingers
against

frostbite

by

refrigerant
If

any
of
the

refrigerant
should

get
into

your
eyes

when

charging
the

refrigerant
splash

your
eyes
with

cool
water
to
raise

the

temperature
gradually
Apply
a

protec

tive

film
to

the

eye
to

avoid
infection

Do
not
rub

your
eyes
Consult
an

eye

specialist
Always
wear

goggles
or

glasses
to

protect
your
eyes
when

working
around
the

system
Should

refrigerant
strikes

your
body
splash

on
cool
water
and

apply
a

protective

film

2
The

refrigerant
service
container

has
a

safe

strength
However
if
han

dled

incorrectiy
it
wili

explode

Therefore

always
follow
the
instruc

tions
on
the

label
In

particular
never

stpre
it
in

a
hot

location
above

S20C

l250F
or

drop
it
from

a

high

height

3
The

refrigerant
gas
is

odorless
and

colorless
and

breathing
may
become

difficult

due
to
the

lack
of

oxygen

Since
the

refrigerant
gas
is

heavier
than

air
and

will

lay
close
to
the
floor
be

especially
careful
when

handling
it

in

small

confined

spaces

4

The

refrigerant
itself
is
nonflam

mable
However
a

toxic

gas

phosgene

gas
is

produced
when
it

contacts
fire

and

special
care
is
therefore

required

when

checking
for

leaks
in

the

system

with

a
halide
torch

5

Do
not
steam

clean
on
the

sys

tern

especially
condenser
since
exces

sively
high
pressure
will
build

up
in

the

system
resulting
in

explosion
of
the

system

The

above

precautions
are
essential

in

handling
of

Refrigerant
l
2
and

their
strict
observation

requires
suffi

AC
9
dent

training
Therefore
it
is

of
first

importance
that

any
other

personnel

than
a
well
trained
serviceman
should

not
be

allowed
to
handle
the

refrig

erant

EVACUATING

AND

CHARGING
SYSTEM

During

servicing
use
caution
to

keep
air

from

getting
into

refrigerant

When
air

enters
the

system
all

refriger

ant

must
be
evacuated
from

system

prior
to

charging
new
refrigerant
Air

in

refrigerant
has
the

following
delete

rious

effects

I

Since
the
condensation

tempera

ture

of
the
air
is

extremely
low
the
air

will

not
be

condensed
when

refrigerant

gas
is
condensed

in
the
condenser
and

the

air
will

thus
remain
in

gaseous

form

Consequently
the
effective

thermal

transmission
area

of
condenser

for

refrigerant
gas
will
be
red
uced
and

refrigerant
gas
to
be
condensed
will
be

red
ueed
The

pressure
rise
will
become

proportional
to

the
volume
of
the
air

in

system

2

When
air
and

refrigerant
are

mixed
in

system
a
chemical
reaction

will
be

produced
and

hydrochloric

acid
which
will

adversely
affect
the

aluminum

copper
iron
and
other

materials
in

system
may
be

generated

HANDLING
MANIFOLD

GAUGE

The

pressure
at
the

high
and
low

sides
of

system
should
be

measured

when

evacuating
and

charging
refrig

erant
and
when

diagnosing
trouble
in

the

system
The
manifold

gauge
is
used

for
these

purposes
A

manifold

gauge

has
two

pressure
gauges
a

low

pressure

gauge
and
a

high
pressure
gauge
These

gauges
are

connected
to

the

high
and

low

side
service

valves
of

system

through
flexible

charging
hoses

The

construction

of
manifold

gauge
is

shown
in

Figure
AC
13

When
valve
stem
is

fully
screwed

the
valve
is
front
seated
and
valve

path

and
the
center

path
are
blocked
When

valve
stem
is

backed
off
the

paths
are

opened

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

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