height DATSUN PICK-UP 1977 Owner's Manual

s

Install
tension

rod
at
rear
end

tighten
nut
to

make
the

distance
of

rubber

bushing
to
be
33
4
mm
1
315

in
and

torque
lock
nut
to
1

6
to
2
2

kg
m
12

to
16
ft
lb

6

Install
tension
rod
bracket

to

chassis

frame
bracket
and

torque
nut

to
1

6
to
2
2

kg
m

12
to
16
ft
lb

When

two
rubber

bushings
are
dif

ferent
in
size

arrange
adjusting
nut

Standard
dimension
is
11
0
mOl
0
433

in

as
shown
in

Figure
FA

16

Torque

lock
nut

to
1
6
to
2
2

kg
m

12
to
16

ft
lb

Il
0

11

0
0
433

t

lP

33
4
1
315

I

11
0

0
433
1
0
11
0

0

433

Adjusting
nut

Y
i

w

36
6
l
441

Unit
mm

in

FA235

Fig
FA
16
Tension
rod
detail

INSPECTION

I

Check
tension

rod
for
bend
and

the

thread
for

faulty
condition

Repair

or

replace
as

required

2

Check

bushing
rubber
for
wear

and
deterioration

Replace
if
neces

sary

TORSION

BAR

SPRING

REMOVAL
AND

INSTALLATION

Removal

1
Raise
vehicle
on
a
hoist
or
stands

2
Remove
wheel

3
Loosen
nuts
at

spring
anchor

bolt
Front
Axle
Front

Suspension

4
Remove
dust

cover
at
the
rear

end

of
torsion
bar

spring
and

detach

snap

ring

S
Withdraw
torsion
bar

spring
rear

ward

after

pulling
ou
t
anchor
arm

realWard

I

nstallalation

Install
torsion
bar

spring
in
the

reverse

sequence
of

removal

noting

the

following
instructions

I

Coat

grease
on
the
serrations
of

torsion
bar

spring
and
install
it

to

torque
arm

Note
Be

sure
to
install

right
and
left

torsion
bar

springs
correctly
They

can

be
identified
with
R

Right

and
L

Left
marked
on
the
end

surface

2
Install

anchor
arm
and

tighten

adjusting
nut
to

obtain
A
dimen

sion
See

Figure
F
A
17

When
anchor

arm
is

properly
adjusted
to
A

specification
upper
link
should
be
in

contact
with

rebound

bumper
rubber

See

Figure
FA
18
Install

snap
ring
and

dust
cover

Temporarily
tighten

adjust

ing
nut
until
B

specification
is

reached

I

I

I

FA236

Fig
FA
17

Installing
anchor
arm

Specifications
for
torsion
bar

spring

Diameter
x

length
mOl

in

Torsional

rigidity

kg
m

deg
ft
lb

deg

FA
9
Anchor
arm

setting
post
ion
A

ISt02Smm

0
59
to

0
98
in

Temporary
tightening
distance
B

60
to
70

mOl

2
36
to
2

76
in

UjPPje
Rebound

bumper

rubber

j

4W

Fig
FA

18

Setting
procedure

Notes

3
A

and
8

specifications
are

only
the

preliminary
rough
settings

directions
for

performing
the
final

adjustment
that

determines
the
ride

height
are
found
on

page
F
A
II

under

Adjustment

b
Discard
old

snap
ring
after

re

moving
it

Replace
with
new

one

during
reinstallation

3
Install
wheel
and

lower
vehicle

Adjust
vehicle

posture
at
curb

weight

full
fuel

tank
no

passengers
refer

ring
to

Adjustment

4

Torque
lock
nut
to
3
1
to
4
1

kg
m
22
to
30

ft
lb

INSPECTION

Check
torsion
bar

spring
for
wear

twist
etc
When

adjusting
vehicle

posture
replace
torsion
bar

spring

with
a
new
one
if
the

specified
height

can
not

be
obtained

All
models

21

9
x
830
0
862
x

32
68

3
74
27
I

Front
Axle
Front

Suspension

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Vibration
shock
and

shimmy

ing
of

steering
wheeL

Vehicle

pulls
to
right
or
left
Probable
cause

Vibration
Too

much
backlash
of

steering

gear
wear

of
each

part
of

linkage
and
vibration
of
front

wheels
are
in

many
cases
transmitted
to
the

steering
wheel
This
is

Very
much
noticeable
when

traveJling
over
bad
roads
and
at

higher

speeds

Shock
When

the
front
wheels
are

travelling
over

bumpy
roads
the

play
of
the

steering
linkage
is

transmitted
to
the

steering
wheel
This
is

especially

noticeable
when

travelling
rough
road

Shimmy
Abnormal
vibrations
of
the
front

suspen

sion

group
and
the
whole

steering

linkage
which

occur
when

a

specific
speed
is
attained

Improper
air

pressure
of
tire

Unbalance
and
deformation
of
roadwheel

Unevenly
worn
tire
or

insufficient
tightening

Improperly
adjusted
or

worn
front
wheel

bearing

Faulty
wheel

alignment

Worn
or
loose

suspension
link
screw

bushing

Damaged
idler
arm

Insufficiently

tightened
steering
gear
housing

Worn

steering
linkage

Improper
steering
gear
adjustment
insufficient
back

lash

Faulty
shock
absorber
or
loose
installation

Unbalanced
vehicle

posture

When

driving
with
hands
off
the

steering
wheel

on
a

fiat
road
the
vehicle

gently
swerves
to

right
or

left

Note
A

faulty
rear

suspension
may
also
be
the
cause

of
this
condition
and
therefore
see
also
the

chapter
dealing
with
the
rear

suspension

Improper
air

pressure
of
tire

or
insufficient

tightening

of
wheel
nu
ts

Difference
in

height
of

right
and
left
tire
treads

Incorrect

adjustment
or
abrasion
of
front
wheel

bearing

Weakened
front
torsion

spring
or
deviation
from

standard

specification

Improper
wheel

alignment

Worn

or
loose

suspension
link

screw

bushing

FA
14
Corrective
action

Adjust

Correct
the
unbalance

or
re

place

Replace
or
tighten

Adjust
or

replace

Adjust

Replace

Replace

TIghten

Replace
ball

joint

Adjust

Replace
or

tighten

Adjust

Adjust
or

tighten

Replace
tires

Adjust
or

replace

Replace

Readjust

Replace

The
620

series
vehicles

are
equip

ped
with

hydraulic
brakes

on
the
four

wheels
and
mechanical
hand
brakes

on

the
rear
wheels
The
front
brake
is

the
uni
servo

type
and
the
rear
the

duo

servo
with
the
built
in

hand

BRAKE
PEDAL

FRONT
BRAKE

REAR
BRAKE

BRAKE
PEDAL

Qi

f

l

II

t

Unit

mm
in

I
Under
the
condition
that
the

push
rod
of
brake

lamp
swi

tch
is

pushed
in

position
the

height
of
brake

pedal
from
toeboard
to
148
mm
5
83

in

operating
the
switch

adjusting

nuts
Then

tighten
nuts

securely

Tightening
torque

1
2

to
1
5

kg
m

9
to
I
I
ft
Ib

2

Adjust
the

length
of

push
rod
Brake

System

GENERAL
DESCRIPTION

brake
The
mechanical
hand
brake
is

controlled

by
a
hand
brake
lever
locat

ed
in
the
driver

s

compartment

For
added

safety
the
tandem

I
1lI3ter

cylinder
Master
Vac
and

Nissan
Load

Sensing
Valve
N

L
S
V

ADJUSTMENT

CONTENTS
are
standard

equipment
on
all
models

The
Master
Vac
is
installed
to
increase

braking
force
The
N
L

S
V
ensures

greater
safety
and

reliability

BR
2

BR
2

BR
3
HAND

BRAKE

Parking
brake

BLEEDING
HYDRAULIC
SYSTEM
BR
3

BR
3

Free

height

Full
stroke
at

pedal
pad
A
148

5
83

B
134

10
140

5
28
to
5
51

C
43
to
49

1
69

to
1
93
Depressed
height

1
Push
rod

adjusting
nut

2
Switch
adjusting
nuts

3
BraKe

lamp
switch

BA765

Fig
BR
l

Adjusting
brake

pedal

with
its

adjusting
nut
so
as
to
become

0
6
to
1
2
mOl
0
024
to
0

047
in
in

play
Then

tigh1en
nut

securely

Tightening
torque

1

6
to
2

2

kg
m

12

to
16
ft
lb

Note
Take
care
not
to
allow
the

push

rod
to

get
into
master

cylinder
in

free
condition

BR

2
3
After
completing

adjustment

operate
brake

pedal
several
times
to

ensure
that
it
travels
over
its
entire

stroke
of
137
mm
5

39
in

smoothly

without

showing
squeak
noise
twist

ing
or
interference

FRONT
BRAKE

1
Raise

vehicle
until
wheel
clear

floor

2

Remove
rubber
boot
from
brake

disc

3

Ughtly
tap
adjuster
housing
and

move
it

forward
Turn
down

adjuster

wheel
with
a

screwdriver
and

spread

brake
shoes

Stop
turning
adjuster

wheel
when
a
considerable

drag
is
Jelt

and
lock

up
brake
drum

Note
For
both

right
and
left
brakes

brake
shoes

spread
when

adjuster

wheel
is
turned
downward

4
Return

adjuster
wheel
12
ratches

to
obtain
correct
clearance
between

brake
drum
and
brake
shoes
Turn

brake
drum
and
make
sure
that
brake

drum
turns
without

dragging
when

brake
shoes
interfere
with
brake
drum

then

readjust
clearance

5

Install
rubber
boot

Brake

System

SERVICE
DATA
AND
SPECIFICATIONS

Brake

pedal

Free

height

Free

play
at

pedal
pad

Full
stroke

at
pedal
pad

Depressed
height
mOl
in

mOl
in

mOl
in

mm
in
148
S

83

I
to
3
0

04
to
0

12

134
to
140
5
28
to
S
51

43
to
49

169
to
193

Brake

adjustment
notches

Front

Rear
12

12

Master

cylinder

Inner
diameter

Piston
to

cylinder
deaJance
mm
in

mm
in
19
0S

Yo

O
IS

0
OOS9

Master
Vac

Diaphragm
diameter
mOl
in

Maximum
vacuum
leakage
after
15
sec

mmHg
inHg

Shell
seal

depth
A
mOl
in

Push

rod

length
B
mOl
in
152
4
6

2S
0
98

6

7
to
7
0

0
264
to
0
276

10

0
to
10
5
0
394
to
0
413

Front
drum
brake

Type

Wheel

cylinder
inner
diameter

Lining

Width
x
Thickness
x

Length

Lining
wear
limit
Uni
servo

mm
in
I9
0S

Yo

45
x

4
5
x

244

1
77
x
0
177
x
9
61

1

0
0
039
mm
in

mOl
in

Rear
drum
brake

Type

Wheel

cylinder
inner

diameter
Duo
servo

mOl
in
19
0S

Yo

Brake

drum

Inner
diameter

Repair
limit
of

thickness

Inside
runout
mm
in

mOl
in

mOl
in
254
0
10

2SS
S
10
06

0
02
0
0008
maximum

PaJking
brake

Type

Stroke

Adjuster
sliding
resistance
mm
in

kg
lb
Stick

type

80
to
100
3
lS
to
3
94

S

to
12
11

to
26

BR
20

Condition

Excessive

pedal
travel

Spongy

pedal

Poor

braking
effect

Brakes

drag
Brake

Syst
em

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Probable
cause

Low
brake
1uid
level
or

empty
master

cylinder
reservoir

Leakage
in
master

cylinder

Deteriorated
check
valve

Air
in

system

Faulty
brake

adjustment

Low

1uid
level
in
master

cylinder

Air
in

system

Faulty
brake

adjustment

Reservoir
filler

cap
vent

hole

clogged

Swollen
hose
due
to
deterioration

or
use
of

poor
quality
hose

Distorted

brake
shoes
or

excessively
worn

or

cracked

brake
drum

Soft
or
swollen

caliper
seals

Use
of
a
brake

1uid
with

too
low

boiling

point

Fluid

leakage
in

brake
lines

Low

brake
1uid
level

or

empty
master

cylinder
reservoir

Air
in

brake
lines

Excessive
shoe
ta
drum

clearance

Grease
oil

mud
or

water
on

linings
or

pads

Deterioration
of

linings
or

pads

Local
fit
of

linings
or

pads

Linings
or

pads
excessively
worn

Master

cylinder
or
wheel

cylinders
in

poor

condition

Binding
mechanical

linkage
at
brake

pedal

and
shoes

Clogged
brake
lines

Incorrect

adjustment
of

wheel

bearings

Improper
shoe
t

drum
clearance

Weak
shoe
return

springs

No
free
travel
in

brake
shoe

return

BR
22
Corrective
action

Fill
and
bleed
as

necessary
Test

for
source

of

leakage
by
examining
all
lines

connec

tions

and
wheel

cylinder

Overhaul
master

cylinder

Replace
check
valve
and
bleed

system

Bleed

system

Adjust
shoe
to
drum
clearance

Inspect

auto

adjuster
operation

Top
with
1uid
and

inspect
for

leakage

Correct
as

necessary

Adjust
shoe
to

drum
clearance

Inspect

aut

adjuster

operation

Clean
and

bleed

system

Replace
hose
and

bleed

system

Replace
faulty

parts

Drain

hydraulic
system
flush
with
alcohol

and

replace
all
seals

Replace
with

specified
brake

1uid
and
bleed

system

Check

master

cylinder

pIpIng
and
wheel

cylinder
for
leaks
and

repair

Fill
and
bleed

as

necessary

Bleed

system

Adjust

Clean
brake
mechanism
and
check
for

cause

of

problem

Replace
linings
or

pads

Replace

Shave
or

replace

Replace

Repair
or

replace

Free

up
as

required

Check
and

clean

Adjust
or

repair

Adjust

Replace

Adjust

pedal
height

Engine
Control
Fuel
Exhaust

Systems

REMOVAL
AND

INSTALLATION

Accelerator

wire

I

Remove
air
cleaner

assembly

2

Disconnect
accelerator
wire

from

carburetor

3

Loosen
lock

nut
and
disconnect

accelerator
wire
outer
case
from
wire

holder
See

Figure
FE
I

4

Remove

spring
clamp
and

discon

nect
accelerator
wire

from
accelerator

pedal
arm

S

Remove
two

screws

securing
ac

celerator
wire
outer
case
to

body
and

detach
accelerator
wire

6
To

install
reverse
the
order

of

removal

Apply
recommended
multi

purpose
grease
slightly
to

portion

MG
shown
in

Figure
FE
I

Accelerator

pedal
assembly

I
Remove

spring
clamp
then
dis

connect
accelerator
wire
from

tip
of

pedal
ann

2
Remove

two
screws

securing
ac

celerator

pedal
bracket

to

body

3
Remove

accelerator

pedal
from

dash

panel
See

Figure
FE
I

4
To
install
reverse
the
order
of

removal

INSPECTION

I
Check
accelerator

pedal
return

spring
for

rust

fatigue
or

damage

Replace
if

necessary

2

Check
accelerator
wire

cases
and

fastening
locations
for
rust

damage
or

looseness

Repair
or

replace
if

necessary

ADJUSTMENT

Accelerstor

pedal
and
wire

Adjust
pedal

stopper
bolt

Section
A

so
as
to
obtain

specifi

ed

height
E
as
shown
in

Figure

FE
I

Secure

pedal
stopper
bolt
with

stopper
lock
nut
Refer

to
Figure

FE
I
E

78
mOl
3
07

in

Tightening
torque
01
nut

0
38

to
0
4S

kg
m

2

7
to
3
2

ft
b

2

Release
auto

choke
effect
since

throttle
lever
is

opened
by
fast
idle

earn
until

engine
warms

up

I

Keep
choke
valve

fully
open

with

fingers

2

Pull
throttle
lever

up
by
hand

1

Adjust
nut

2
Lock
nut

3
Accelerator
wire

4
Dust
co

r

5
After

completing
the

adjustment

as

previously
explained
check
the

following

I

Make
sure

that
accelerator

system
functions

smoothly
and

quietly

without

disturbing
any
adjacent

parts

2

Depress
accelerator

pedal
down

until

throttle
valve

fully

opens
Make

sure
that

the
clearance
T
between

accelerator

pedal
reverse
side
and
dash

floor
is
2
to
4
mm
0
08
to

0
16
in

without
floor

mat

Adjust
pedal

stop

per
bolt
and
lock
nut
if

beyond
limits

3

Check
throttle

lever
if
it

returns

to
the

original
position
as
soon
as

accelerator

pedal
is

released

FE
3
then
automatic

choke
effect
will

be

released

3

Set
throttle
valve
to

completely

closed

position
and
with
wire

suf

ficiently
slackened

lighten

adjust
nut

until
throttle
lever
is
about
to
move

Accelerator

pedal
play
is

zero

at
this

lime
See

Figure
FE

2

4

Unscrew

adjust
nut

approxi

mately
two
and
a

half
turns
so
that

accelerator

pedal
play
is
3
mOl

0
012

in

Tighten
lock
nut

securely
See

Figure
FE
2

1

I

1

CD
@

FE184

Fig
FE72

AdjU6ting
accelerator
wire

play

4

Apply
recommended
multi

purpose
grease
slightly
on
the

portion

as
shown
in

Figure
FE
I
Also
refer

to

the

periodic
maintenance
schedule

Kickdown
switch
Automatic

transmission
models
only

Kickdown
switch

adjustment
is

cor

rect
if
it
is

actuated

by
kickdown

switch
striker
when

accelerator

pedal

is

fully

depressed

Always
tighten
switch

stopper
nut

securely
after

proper
adjustment
is

obtained

6
Attach

lifting
ropes
to
hooks
in

rear
body
as
shown
in

Figure
BF
8

and
lift

up
rear
body
slowly
and

carefully

Notes

a
When

lifting
rear

body
make
sure

that
it
is
in
a

good
balanced
cond

ition

b
While

lifting
use
care
not
to
allow

rear

body
to
hit

against
cab

body
or

any
adjacent
parts

c
The
rear

body
weighs

approxillll
te

Iy
130

kg
286
Ib

BF0288

Fig
BF

8

Lifting
up
rear

body

7
To
install
rear
body
reverse
the

order
of
removal

Carefully
observe

the
following
instructions

Make
sure
that

spacers
and
shims

used
with
bolts
are

properly
placed

in
their

original
positions
Refer
to

Figure
BF
6
for

the
location
of
these

parts

The
rear

body
to
frame

attaching

bolts
should
be

torqued
to
3
3
to
4
2

kg
m
24
to
30
ft
Ib
Body
Frame

REAR
GATE

00

REMOVAL
AND
INSTAllATION

1

W

@

BF661

I

Open
rear

gate

2

Remove
rear

gate
chain
from
ear

gate

3
Remove

rear

gate
hinge
attaching

bolts
and

take
out
rear

gate
and
rear

gate
hinge
shims

4

To
install
rear

gate
reverse
the

order
of
removal

ALIGNMENT

The
rear

gate
should

be

adjusted
so

that
there
exists

an

equal
clearance

between

body
and
the

periphery
of

rear

gate
There
should
be
no

stepped

portion
at

any
points

I

To

adjust
the

height
of

rear

gate

add
or
remove
shims
at
rear

gate
hinge

Two
sizes
of
shim
are
available
in

thickness
1
6
mm
0
0630
in
and
0
8

rom
0
0315
in

rr

r

f

r

@

C
L

i

BF
6
1
Rear

gate
chain

2
Rear
gate
chain

bolt

3
Rear

body

4
Shim

S
Hook
handle

6
Reargate

Fig
BF
9
Rear
gate

2
To

adjust
rear

gate
in

the
left
and

right
directions
loosen
rear

gate
hinge

attaching
bolts
and

move
rear

gate
as

required

3
To

adjust
rear

gate
hook
loosen

two

attaching
bolts
and
move
rear

gate

hook

up
down
or
left

right
in
elon

gated
holes
as

required

GUARD
FRAME

Optional

REMOVAL
AND

INSTAUATION

The

guard
frame
is
furnished
as
an

optional
equipment

I

Remove
nine

guard
frame
at

taching
bolts
and

detach

guard
frame

2

To
install

optional
guard
frame

reverse
the
order
of
removal

s

SF673

Fig
BF

lO
Guard

frame

COWL
TOP
GRILLE

@
@

REMOVAL
AND

INSTALLATION

I

Open
engine
hood

2
Remove
two
windshield

wiper

blad

3

Remove
cowl

top

grille
attaching

HOOD

REMOVAL
AND

INSTALLATION

1

Place

protective
covers
over
front

fender
and
cowl

top

grille

2

Open
engine
hood
Mark

hinge

locations
on
hood
and
loosen
off
four

bolts

securing
hood
to
hood

hinge
Use

extra
caution

to
avoid

damaging

painted
surfaces
of
fender
and
cowl

top
grille

3

Remove

engine
hood

4

To
install
reverse
above

pro

cedures

ADJUSTMENT

Four

slotted
holes
in

hood

hinge

provide
for

fore
aft
and
side

adjust

ment

to
correct

space
between
hood

and
fender

and
hood
and

cowl

top

grille

Loosen

four
bolts

just
enough
to

move

engine
hood

and
move
hood
to

desired

position
if

necessary
to
correct

space

To
make
vertical

adjustment
adjust

height
of

dove
tail

bolt
at
hood

lock

male
until
hood
is
flush
with
fender
Body
Frame

1

Cowl

top
grille

2

Cap

3
Air
box
dtain
seal

4

Cowl

top

5

Air
box
drain

6
Screw

6F633

Fig
BF
13
Cowl

top
grille

screws
Pull

grille
straight
forward
to

remove

4
Remove
air

box
drain

5

To
install
reverse
above

steps

HOOD

Loosen
hood
to

hinge
bolts

just

far

enough
to
permit
movement
of

hood

2
Shift
hood
in

elongated
hole
until

parallel
space
is
reached
between
hood

and
fender
or
cowl

top
grille
Tighten

bolts

securely

BF

8
However

observe
the

following
items

I
When

installing
air
box
drain

apply
adhesive
to
its
lower
end

2

Align
cowl

top

grille
with
fend

ers

FRONT
FENDER

REMOVAL
AND

INSTALLATION

I

Remove
front

bumper

2
Remove
radiator

grille

3

Remove
front

apron

4
Remove
cowl

top
grille

S
Remove
hood

bumpers
two
on

each
side

6

Remove
nine

screws

attaching

front
fender
to
hood
ledge
See

Figure

BF
ll

7
To

install
reverse
above

steps

5

1
Female
lever

2

Safety
catch
lever

3
Return

spring

4
Dove
tail
bolt

S
Lock
nut

6
Hood
lock

pring

7

Spring
J

BF641A

Fig
BF
14
Hood
lock
male
and

female

j

I

8F635

Fig
BF
15

Engine
hood

alignment

Body
Frame

Note
Vertical

adjustment
should
be

carried
out
after
hood
lock
male

and
female

adjustment
has

been

completed

3

To
correct
hood
lock

alignment

loosen

two
hood
lock
male
attaching

bolts
and

move
hood

lock
male
and

female
in

the
lateral
and
fore

and
aft

directions
as

required
D

1r

r

BF642A

Fig
BF
16

Adjusting
hood
lock

male

Tightening

torque

Male
and
female

attaching
bolts

0
45

to
0
60

kg
m

3
3

to
4
3

ft
Ib
4
Dove
tail
bolt
at

hood
lock
male

provides
for
vertical

adjustment
in

aligning
hood

to
make
it
flush
with

fender

To
correct
loosen

lock
nut
on

dove
tail

bolt
and
turn
dove
tail
bolt
in

or
out

as

necessary
to
obtain
a

correct

height

HOOD
LOCK
CONTROL

JI

I

i
I

r

lPP

J
jJ
J

Sr

aj
I

I
I

J

f
ifry
ff
I
ii1iiilliii
j
iW

r
U

I

j
Y

f
7

j

1

JJ
J

8F
9
5

Tighten
lock

nut
firmly
while

holding
dove
tail
bolt
with
a

screw

driver

to
secure

adjustment

Tightening

torque

Lock

nut
of

dove
tail

1
9

to
2
6

kg
m

14

to
19
ft
lb

BF643A

1
Lock

nut

2
Hood
lock

male
3

Safety
catch

Fig
BF

17
Doue
tail
bolt

height

adjustment

1
Dove
tail
bolt

seat

2

Lock
nut

3
Cushion
rubber

4

Spring

5

Spring
retainer

6
Dove
tail
bolt

7

Clamp

8

Clamp

9
Hood
lock

female

10
Control
cable

assembly

BF644A

Fig
BF
18
Hood
lock
and
control
cable

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