change time DATSUN PICK-UP 1977 Service Manual

r

ADJUSTMENT
OF
SET

PRESSURE
OF
BOOST

CONTROLLED
DECELERATION

DEVICE
B

C
D
D

Generally
it
is

unnecessary
to

ad

just
the
B
C
D

D
however
if
it

should

become

necessary
to

adjust
it

the

procedure
is

as
follows

Prepare
the

foUowlnB
tools

I

Tachometer
to
measure
the
en

gine

speed
while

idling
and
a
screw

driver

2
A

vacuum

gauge
connecting
pipe

Note
A

qui
k

response
type
boost

gauge
such
as
Bourdon
s

type
is

recommended
a

mercury

type

manometer
should
not
be
used

To

properly
set
the

B

C
D
D

set

pressure

proceed
as

follows

I

Remove
the

harness

of
solenoid

valve

TO
D
D

solenrod

VT

FJ

1
B
C
D
D

solenni

valve
harness

J

ri

y

EF262

F
g
ET

32
Removing
harneS5

of

solenoid

valve

2
Connect
rubber
hose
between

vacuum

gauge
and
intake
manifold
as

shown

Fig
ET

33

Connecting
vacuum

gauge

3

Warm

up
the

engine
until
it
is

heated
to

operating

temperature

Then

adjust
the

engine
at
normal
Engine
Tune

up

idling
setting
Refer
to
the

item

Idling
Adjustment
in

page
ET
II

Idling

engine
speed

Manual
transmission

750

rpm

Automatic
transmission

in

D

position

650

rpm

4

Run
the

engine
under
no

load

Increase

engine
speed
to
3
000
to

3
500

rpm
then

quickly
close
throttle

valve

5
At

the
time
the

manifold
vacuum

pressure
increases

abruptly
to
600

mmHg
23
62

inHg
or
above

and

then

gradually
decreases
to
the
level

set
at

idling

6
Check
that
the

B
C
D
D
set

pres

sure
is
within
the

specified
pressure

Specified

pressure
0
m
sea
level

and

760

mmHg
30

inHg
atmos

pheric
pressure

Manual
transmission

510
to

550

mmHg

20
1
to
21
7

inHg

Automatic
transmission

490
to
530

mmHg

19
3
to
20

9

inHg

Note

When

checking
the
set

pressure

of
B
C
D
D

find
the

specified
set

pressure
in

Figure
IT

36
from
the

atmospheric
pressure
and
altitutde

of
the

given
location

For

example
if
a

manual
transmis

sion

model
vehicle
is

located
at

an

altitude

of
1
000
m

3
280
ft
the

specified
set

preSsure
for
B

C
D
D

445

mmHg
17
5

inHg

7

If
it
is

higher
than
the
set

level

turn
the

adjusting
screw

counter

clockwise

or
nut

clockwise
until

correct

adjustment
is

made

Non
California

models

Adjusting
screw

type

California

models

Adjusting
nut

type

Note
When

adjusting
B
C
D
D

for

California

models
turn

adjusting

nut
in

or
out

with
lock

spring
in

place

Always
set

lock

spring

prop

erly
to

prevent

changes
in
set

pres

sure

ET

18
Non
california

models

1

Adjusting
screw

2

Cover
e

ET037

California
models

r

1

Adjusting
nut

2

Lock

spring

EC692

Fig
ET
34

Adjusting
Bet

pressure

8

Race
the

engine
and
check
for

adjustment

9
If
it
is

lower
than
the
set
level

turn
the

adjusting
screw
or

nut
until

correct

adjustment
is
made

10
Race
the

engine
and
check
for

adjustment

If

engine
speed
cannot

be
decreased

to

idling
when

checking
B
C
D
D
set

pressure
proceed
as
follows

When
the

engine
speed
does

not
fall

to

idling
speed
it

is

necessary
to

reduce
the

negative
idling

pressure
of

the
manifold
to
lower

than
the
set

pressure
of
the
B

C
D

D
The

engine

speed
will
not

drop
to

idling
speed

when
the

negative
idling
pressure
is

higher
than
the

set

pressure
of

the

B

C
D
D

In

this
case
the

engine
must
be

labored

by
I
road
test
or
2
chassis

dynamometer
or
3

by
raising
up
rear

suspension
member
on
a

stand
accel

erating
the
vehicle
to
64
to
80

krn
h

40

to
50
MPH
in

top
gear
manual

transmission
or
in
D

position
auto

matic
transmission

and
then

releasing

the
accelerator

pedal
and

letting
the

vehicle

decelerate
After

doing
this

check

whether
the
B

C
D
D
set

pres

sure
is
at
the

predetermined
value

or

not

Notes

a

The
idle

rpm
and
CO

vary
accord

ing
to
the
altitude
Therefore

they

should
be

properly
adjusted
when

the

position
of
the
H
L
lever
is

changed

EF729

ADJUSTMENT

AND
INSPECTION

CARBURETOR
IDLE
R
P
M

AND
MIXTURE
RATIO

Cautions

3
On

automatic
transmission

equi

ped
models
check
should
be

per

formed
in

the
0

position

Be
sure
to

engage

parking
brake
and

to
lock
both
front
and

rear
wheels

with
wheel
chocks

b

Keep
your
foot
down
on
the
brake

pedal
while

depressing
the
accelera

tor

pedal
Otherwise
vehicle

surges

forward

dangerously

Notes

a
00
not

attempt
to
screw
the
idle

adjusting
screw
down

completely

Ooing
so
could
cause

damage
to

tip

which
in
turn
will
tend
to
cause

malfunctio11ll

b
If
idle
limiter

cap
obstructs

proper

adjustment
remove
it

To
install
idle
limiter

cap
refer
to

Idle
Limiter

Cap

c
After
idle

adjustment
has
been

made
shift
the
lever
to
the
N

or

P

position
for
automatic
trans

mission

d
When

measuring
CO

percentage
in
Engine
Fuel

b
Counties
1

219
m
4
000
ft
or

more
above
sea
level
have
been

designated
by
law
as

High
Altitude

Counties
For

further
details
refer

to
1977
OATSUN
PICK
UP
Service

Bulletin
Pub
No
257

0

I
Air
cleaner

rID
mOl

If
Low
altitude

Ll

n
n

L
n

Fig
EF
34

sert

probe
into
tail

pipe
more
than

40
em

15
7
in

CO
Idle

adjustment
with

CO
meter

Idle
mixture

adjustment
requires

the
use
of
a

CO
meter

especially
for

California
models
When

preparing
to

adjust
idle
mixture
it
is

essential
to

have

the
meter

thoroughly
warmed

up

and

calibrated

I

Check
carburetor

pipes
for

proper

connection

2
Warm

up

engine
until
water

tem

perature
indicator

points
to
the
middle

of

gauge
The

procedure
to
warm

up

engine
is
not

specifically
recom

mended
Either

driving
vehicle
or

oper

ating
engine
at

no
load
will

be

good

3
Make
sure
that
water

tempera

ture
indicator

points
to
the
middle

Further

keep

engine
running
at
about

2
000

rpm
for

about
5

minutes
with

out

applying
load
to

engine
in

order
to

stabilize

engine
condition

Engine

hood
should
be

open

4
Run

engine
for
about

10
minutes

at

idling
speed
Ouring
this
10

minutes

proceed
as
described
in

steps

5

to
9
below

5
Remove
air

hose
between
3

way

connector
5

way
connector
for
Cali

fornia
models
and
air

check
valve
as

EF
21
shown
in

Figure
EF
35

Plug
the
dis

connected
hose

to

prevent
dust

from

entering

0

o

EF259

Fig
EF
35
Disconnecting
air
hose

from
air
check
valve

6
Race

engine
I
500

to
2
000

rpm

two
or
three
times

under
no
load
then

run

engine
for
one
minute
at

idling

speed

7

Adjust
throttle

adjusting
screw

until

engine
is

at

specified
speed

Engine
speed

Manual
transmission

750

rpm

Automatic
transmission

in
0

position

650

rpm

8
Check

ignition
timing
If
neces

sary
adjust
it
to

specifications

This

operation
need
not
be
carried

out
at
1

600
Ian
1

000
miles
service

Ignition
timing

Manual
transmission

120
750
rpm
Non
California

100
750

rpm
California

Automatic
transmission

in
0

position

120

650

rpm

9
At

about
10
minutes

after

engine

is
run

at

idling
speed
adjust
idle

adjusting
screw
so

that
CO

percentage

is
at

specified
level

CO

percentage

Manual
transmission

2
t
l

at
750

rpm

Automatic

transmission

in
0

position

2
t
I
at
650

rpm

10

Repeat

procedures
as
described

in

steps
6

7
and
9
above

so
that
CO

percentage
is
at

specified
level
Check

ing
idle
CO
in

step
9
can

be
carried
out

right
after

step
7

II
Race

engine

1
500
to
2

000

Engine
Electrical

System

SERVICE
DATA
AND
SPECIFICATIONS

D4A4

06
D4A4
07

Type
D4A6
07
D4A6
08

Firing
order
1
3
4
2
13
4
2

Rotating
direction
Counterclockwise
Counterclockwise

Owen

angle
degree
490
to
550
490

to
550

Point

gap
mm
in
0

45
to
0

55
0
45
to
0
55

0
018
to

0
022
0
018
to
0

022

Point

pressure
kg
lb
0
40

to
0
55
0
40
to
0
55

0

88
to
1

21
0
88
to
1
21

Condenser

capacity
JlF
0
20

to
0
24
0
20

to
0
24

Condenser
isolate
resistance
Mrl
5
5

Cap
isolate
resistance
Mrl
50
50

Rotor
head
isolate
resistance
Mrl
50
50

Cap
carbon

point
length
mm
in
10

0
39
10
0
39

For
Canada

DISTRIBUTOR
California
models

CONSTRUCTION

CHECKING
AND
ADJUSTMENT

CAP
AND

ROTOR
HEAD

AIR

GAP

CONSTRUCTION

In
the
conventional
distributor
the

ignition
liming
is

detected

by
the
cam

and
breaker
arm
while
in
this
transis

tor

ignition
unit
it
is

detected

by
the

reluctor
on
the
shaft
and
the

pick
up

coil

provided
in

place
of
the
breaker

The

pick
up
coil
consists
of
a

magnet

coil
etc
The
amount
of

magnetic
flux

passing
through
the

pole
piece
in
the

coil
is

changed
at
the

moment
the

pole
CONTENTS

EE
33

EE
33

EE
33

EE
33
ADVANCE
MECHANISMS

DISASSEMBLY

ASSEMBLY

SERVICE
DATA
AND
SPECIFICATIONS
EE
33

EE
35

EE
35

EE
36

piece
faces
the

protrusion
of
the

re

luctor

and
then
the
electrical

signal
is

genera
ted
in
the

pick
up
coil

This
electric
signal
is

conducted

into

the
transistor

ignition
unit
which

in

turn
breaks
tI
e

primary
coil
current

running
through
the

ignition
coil
and

generates

high
voltage
in
the

secondary

winding
Also
this
transistor

ignition

EE
33
unit

utilizes
this
electric

signal
to

restore
the

primary
coil
to
the

original

state
after

cutting
off
the

primary

current
for
a
fIXed
time

The

centrifugal
and
vacuum
ad

vance
mechanisms

employ
the
con

ventional
mechanical

type
The
con

tactor
is
used
to
eliminate
vacuum

and

centrifugal
advance

hysteresis

I

Inspection

Note
To
clean
or
wash
all

parts
of

master

cylinder

operating
cylinder

and

piping
clean
brake
fluid
must

be
used
Never
use
minera10ils
llUch

as

gasoline
and
kerosene
It

will

ruin
the
rubber

parts
of
the

hydrau

lic

system

I

Check
cylinder
and

piston
for

uneven
wear
or

damage
and
if
neces

sary
replace

2
If
the
clearance
between

cylinder

and

piston
is

more
than

0
15
mm

0
0059
in

replace
cylinder

3

Renew

piston
cup
when
dis

assembled
It
must
also
be

replaced

when
wear
or
deformation
due
to

fatigue
or

damage
is

found

4

Damaged
dust
cover
oil
reservoir

or

cap
should
be

replaced

Return

spring
and
valve

spring
must

also
be

replaced
when

they
are
broken

or
weak

5

Replace
clutch
hose
and
tube
if

any
abnormal

sign
of

damage
or
de

fro

ti

n
is
found

OPERATING

CYLINDER

Removal
and

installation

Removal

1

Detach
clutch
hose
from

operat

ing
cylinder

2
Remove
two
bolts

securing
op

erating
cylinder
to
clutch

housing

Installation

Install

in
the
reverse
order
of
re

moval

Observe
the

following
instructions

Bleed
air

thoroughly
from
clutch

hydraulic
system

2
Do
not

install
return

spring
or

clutch
will

not
be

disengaged

properly

Tightening
torque

Operating
cylinder
securing
bolt

2
5
to
3
5

kg
m

18
to
25
ft
lb

Bleeder
screw

0
7
to
0
9

kg
m
5
1

to
6
5
ft
Ib

Clutch
hose
connector

1
7
to

2
0

kg
m
12
to
14
ft

b
CLUTCH

Disassembly
and

assembly

Disassembly

1
Remove

push
rod
with
dust

cover

2
Remove

piston
assembly
and

pis

ton

spring

3
Remove

bleeder
screw

1
6

Cl11B

5

Piston

cup

6

Operating
cylinder

7
Bleeder
screw
1

Push
rod

2
Dust
cover

3
Piston

spring

4

Piston

Fig
CL
20

Exploded
view

of

operating
cyUnder

Assembly

Assemble
in
the

reverse
order
of

disassembly
Closely
observe
the
fol

lowing
instructions

1

Prior
to

assembly

dip
piston
cup

in

clean
brake
fluid

When

installing
cup
pay
particular

attention
to
its
direction

2

Dip
cylinder
and

piston
in
clean

brake
fluid
before

assembly

Notes

a
Be

sure
to
install

piston
assembly

with

piston
spring
in

place

b
The
clutch

operating
cylinder
is

available
in
both
NABCO
make
and

TOKICO
make
There
is
no
inter

changeability
of

repair
kits
or
com

ponent
parts
between
NABCO
and

TOKICO
makes

When

replacing
the

repair
kit
or

component
parts
ascertain
the

brand
of
the
clutch

operating
cyl

inder

bndy
Be
sure
to
use

parts
of

the

same
make

as
the
former
ones

Inspection

Visually

inspect
all
disassembled

parts
replacing
those
found
worn
or

rl

Q
damaged
too

badly

beyond
speci

fications

BLEEDING
CLUTCH

SYSTEM

The

hydraulic
clutch

system
must

be
bled
whenever
clutch
line
has
been

disconnected
or
air

has
entered
it

When

pedal
action
has
a

spongy

feeling
it
is
an
indication
that
air
has

entered
the
system

Bleeding
clutch

system
is

an
es

sential

part
of

regular
clutch
service

I

Remove
reservoir

cap
and

top
up

with
recommended
brake
fluid

2

Thoroughly
clean
mud
and
dust

from
bleeder
screw
of

operating
cyl

inder
so
that
outlet
hole
is

free
from

any
foreign
rnaterial
Install
bleeder

hose

vinyl
hose
on
bleeder
screw

Place
the
other
end
of
it
in

a
clean

container

3
Have
a
co
worker

depress
clutch

pedal
two
or

three
times
With
clu
tch

pedal
depressed
fully
loosen
bleeder

screw
to
bleed
air
out
of
clutch

sys

tern

4
Close
bleeder
screw

quickly
as

clutch

pedal
is

on
down
stroke

5
Allow
clutch

pedal
to
return

slowly
with
bleeder
screw
closed

6

Repeat
steps
4
and
5
until

no
air

bubble
shows
in

the

vinyl
hose

7

Operate
clutch
several
times

then
check
connections
for
external

hydraulic
leaks

Notes

a
Brake
fluid

containing
air
is
white

and
has
visible
air
bubbles

b
Brake
fluid

containing
no
air
runs

out
of
bleeder
screw
in
a
solid

stream
without
air
bubble

c

Pay
close
attention
to
clutch
fluid

level
in
reservoir

during

bleeding

operation

d
Do
not

reuse
brake
fluid
drained

during
bleeding
operation

e
Exercise
care
not
to

splash
brake

fluid

on
exterior
fInish
as
it
will

damage
the

paint

f
Pour
brake
fluid
into
reservoir

up

to

specifIed
level

CLUTCH

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Probable
cause
and

testing

Clutch

slips
Corrective
action

Slipping
of
the

clutch

may
be

noticeable
when

any
of
the

following
symptoms
is

encountered

during
operation

I
Vehicle
will

not

respond
to

engine

speed
during
acceleration

2
Insufficient
vehicle

speed

3
Lack
of

power
during
uphill
driving

Some
of
the

above
conditions
are
also

experienced
when

engine

problem
is

oc

urring
First

de
tennine
whether

engine
or
clutch
is

causing
the

problem

If

slipping
clutch
is

left
unheeded
wear
and
or

overheating
will
occur
on
clutch

facing
until
it
is

no

longer
serviceable

TO
TEST
FOR
SLIPPING
CLlJfCH

proceed
as
follows

During
upgrade
travelling
run

engine
at

about
40
to
50
km

h
25
to
31

MPH
with

gear
shift

lever
in

3rd

speed
position
shift
into

highest
gear
and
at
the
same
time

rev

up
engine
If
clutch

is

slipping
vehicle
will
not

readily

respond
to

depression
of
accelerator

pedal

Clutch

facing
worn

excessively

Oil
or

grease
on
clutch

facing

W

r
d
clut
h
cov
r

pressure
plat
Replace

Replace

tpa
o
e
lace

Dragging
clutch
is

particularly
noticeable
when

shifting
gears
especially
into

low

gear

TO
TEST
FOR
DRAGGING
CLlJfCH

proceed
as
follows

I
Start

engine
Disengage
clutch
Shift
into

reverse

gear
and
then
into
Neutral

Gradually

increase

engine
speed
and

again
shift
into
reverse

gear
If
clutch
is

dragging
gear
grating

is

heard
when

shifting
from
Neutral
into

Reverse
Clutch

drags

2

Stop
engine
and
shift

gear
Conduct
this
test
at
each

gear
position

3
Gears

are
smoothly
shifted
in

step
2
but

drag
when

shifting
to
1st

speed
position
at

idling

a
If

dragging
is
encountered
at
the
end
of

shifting
check
condition
of

synchro

mechanism
in
transmission

b
If

dragging
is
encountered
at
the

beginning
of

shifting
proceed
to

step
4

below

4
Push

change
lever
toward
Reverse
side

depress
pedal
to
check
for
free
travel

a

If

pedal
can
be

depressed
further
check
clutch
condition

b
If

pedal
cannot
be

depressed
further

proceed
to

step
5
below

5
Check
clutch
control

pedal
height
pedal
free
travel
withdrawal
lever

play
etc

If
no
abnonnal

condition
exists
and
if

pedal
cannot
be

depressed
further
check
clutch

condition

Clutch
disc
runout
or

warped

Wear

or
rust

on
hub

splines
in
clutch
disc

Diaphragm
spring
toe

height
out
of
ad

justment
or
toe

tip
worn

Worn
or

improperly
installed

parts

CL10
Repair
or

replace

Clean
and
lubricate
with

grease
or

replace

Adjust
or

replace

Repair
or

replace

D
RANGE
LOW
GEAR
Automatic

Transmission

The
low

gear
in
D

range
is

somewhat
different

from
that
in
I

range

The
rear

c1utdl
is

applied
as
III

I

range
but

the
one

way
clutch

holds

the

connecting
drum
The

power

now
is

the
same
as
in
1

J
range
That

is

the

power
now
takes

place

through

Ihe

input
shaft
and
into

the
rear

clutch
The

input
shaft
is

splined
to

the

rear
clutch

drum
and
drives
it

Rotation
of
Ihe

rear
clutch
drives
the

rear
clutch
hub

and
front
internal

gear

The
front
internal

gear
rotales
the

front

planetary
gears
clockwise

to

cause
the
sun

gear
to
rotate
counter

clockwise

Counterclockwise

rotation

of
the

sun

gear
turns
the

rear

planetary

gears
clockwise

With
the

rear

plane

tary
carrier

held

stationary
by
the

one

way
clutch
the
clockwise

rotation

of

the
rear

planetary
gears
rotates
the

rear
internal

gear
and
drives

the

flange

clockwise
The

internal
drive

flange
is

splined
to
the

outpul
shaft
and
rotates

the

output
shaft
clockwise

When

the
manual
valve
is

posi

tioned
at
D

the
line

pressure
7

introduced

into
the
manual

valve
is

led

to
the
line

pressure
circuits

l
2

and
3

The

pressure
in

the
circuit
I

acluates
the
rear

clutch
and
the

gover

nor
and
al
the

same
time

operates
the

1st

2nd
shift

valve

CID
to

change
the

speed
The

circuit
2

leads
to

the

second
lock

valve

@
The

circuit
3

actuates

the
2nd
3rd
shift

valve

@

for

the
2nd
3rd

speed

change
and

at
the
same

lime
locks
the

second

lock
valve

@

The

throttle

pressure
16
which

changes
with
the

degree
of
accelerator

pedal

depression

presses
Ihe

pressure

regulator
valve

CD
and

increases
the

line

pressure
7

When

Ihe

speed
of

the

vehicle
has

increased
the

governor

pressure
15

introduced
from

the
line

pressure
circuit
I

actuates
the

I

SI
2nd

shift
valve

CID
2nd
3rd

shift

valve

@
and

pressure
modifier

valve

ID
When
the

governor

pressure

is

high
the

pressure
modifier
valve

ID

acls
in

such
a

direction
as

to

compress

the

spring
and

the

throttle

pressure
is

led
to
the

throttle

pressure
18
This
ATOSO

Fig
AT
30
Power

transmission

during
D

J

range

liIIl

I
IW
L

AT08l

Fig
AT
31

Operation
of
each
mechanism

during
VJ

range

Clutch
low
Band
servo
On

Parking
Cur

Ran
Rllelle

way

pawl
ratio

Front
Rur

brake
Operation
Rekase

ch
lch

Park
on

on

RellerK
2
t82
on
on
on

Neutral

01
low
2
S8
on
on

Orivt
02
Second

1
458
on
on

OJ

Top
1000
on

on
on
on

2
Second
1
458
on
00

t2
Second
1
458
on
on

t

tt
low
2
458
on
on

pressure
acts

against
the
force

of
the

spring
of

the

pressure

regulator
valve

CD
and

also

against
the

throttle

pres

sure

16
thus

lowering
the
line

pres

sure
7

The

governor

pressure
also
increases

with
the

speed
of
Ihe

vehicle

exerting

a

pressure
on

one
side
of

the

lst
2nd
shift
valve

and
counter

acts

the
Ihrottle

pressure
19

line

pressure

AT
20
l
and
the

spring
which

are

exerting

against

t
1e
governor

pressure
There

fore
when

the

governor

pressure
ex

ceeds

Ihis

pressure
the

speed
is

shifted

from

the
I
st

gear
to

the
2nd

gear

The
further
the

accelerator

pedal
is

depressed
the

higher
becomes

the

throttle

pressure
19

increasing
the

governor
pressure
and

shifting
the

speed
change
point
to

the

higher
side

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