1977 DATSUN PICK-UP Service Manual

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

Fip
BR
2

Adjusting
front
brake

REAR
BRAKE

With
hand
brake

fully
released

adjust
rear
brake
shoe
clearance
For

the
service

procedures
refer
to
Front

Brake

Fig
BR
3
Adjusting
rear
brake

HAND
BRAKE

Parking
brake

I
Raise

vehicle
until
rear
wheels
are

clear
of
the
floor

2

Apply
hand
brake
lever

operate

lock
nuts
to
be
80
to
100

mrn
3
lS
to

3
94
in

in
hand
brake
lever
stroke

and
tighten
lock
nuts

securely

Applying
force
to
hand
brake

lever

20

to
30

kg
44

to
661b
Brake

System

1
t

0
t

6

0

I

o

nJ
c

BA655

Fig
BR
4

Adjusting
lock
nut

3

Fully
release
hand
brake
and

rotate
rear
wheels
No

drag
should
be

present

Notes

a
Before

adjusting
hand
brake
com

plete
the

adjustment
of
rear
brakes

b
After

adjusting
hand
brake

operate

the
brake
lever
to
make
cable

stable

c
Hand
brake
must
be

operated

smoothly
while

being

pulled
and

released
Make
sure

that
no
abnor

mal
noise
dragging
twisting
or

other
faulty
condition
occurs

BLEEDING

HYDRAUL
Ie
SYSTEM

Hydraulic
brake

system
must
be

bled
whenever

any
line
has
been
dis

connected
or
air
has

entered
into

system

When

pedal
action
has
a

spongy

feel
it
is
an
indication
that
air
has

entered
the

system

Bleeding
the

hydraulic
system
is

an

essential

part
of

regular
brake
service

BR
3
I

Clean
all
dirt
around
master

cyl

inder
reservoir

I
remove
cap
and

top
up

reservoir

with
recommended
brake

fluid

2

Thoroughly
clean
mud
and

dust

from
bleeder
valve

so
that
outlet

hole

is

free
from

any
foreign
material

Install
a

bleeder
hose
on
bleeder
valve

Place
the
other
end
of
hose
in

a

container

filled
with
brake
fluid

3

Depress
brake

pedal
two
or
three

times
then

keep
pedal
fully
depressed

4

With
brake

pedal
fully
depressed

open
bleeder
valve
to

expel
air

Notes

a

Pay
attention
to
brake
fluid
level
in

master

cylinder
reservoir

during

bleeding

operation

b
Do
not

reuse
brake
fluid
drained

during
bleeding

operation

c

Bleed
air
as
follows

1
Master

cylinder
front

2
Master

cylinder
rear

3
N
L
S
V

front

4
Front

wheels

S
Rear

wheels
left
one
first

6
N
L

S
V

rear

7
N
L

S
V
center

d
Exercise

care
not
to

splash
brake

fluid
on

exterior
finish
as
it

will

damage
the

paint

5

Close
bleeder
valve

quickly
as

brake

pedal
is
on
down
stroke

6
Allow
brake

pedal
to
return
slow

ly
with
bleeder
screw
closed

7

Repeat
bleeding
operations
until

no
air

bubbles
show
in
hose

Notes

a
Brake
fluid

containing
air
is

white

and

has
visible
air

bubbles

b
Brake
fluid

containing
no
air

nms

out
of
bleeder
valve
in
a

solid

stream
free
of
air

bubbles

8

Repeat
above

steps
on
the

re

maining
brake
lines

to

expel
all
air

Brake

System

SERVICE
BRAKE

CONTENTS

BRAKE
PEDAL

REMOVAL

INSPECTION

INSTAllATION

MASTER

CYLINDER

REMOVAL

DISASSEMBl
Y
AND
ASSEMBLY

INSPECTION

INSTAllATION

BRAKE
LINE

REMOVAL

INSPECTION

INSTAllATION

N
L
S
V

DESCRIPTION

N
L
S
V
TEST

FRONT
BRAKE
BR
4

BR
4

BR
4

BR
4

BR
5

BR
5

BR
6

BR
6

BR
5

BR
7

BR
B

BR
B

BR
B

BR
9

BR
9

BR
9

BR
lO

BRAKE
PEDAL

REMOVAL

Remove

pedal
return

spring

I

2

3

4
REMOVAL

DISASSEMBl
Y
AND

ASSEMBLY

INSPECTION

INSTAllATION

REAR

BRAKE

REMOVAL

DISASSEMBLY
AND
ASSEMBLY

INSPECTION

INSTAllATION

MASTER
VAC

DESCRIPTION

INSPECTION
OF

OPERATION

REMOVAL

DISASSEMBLY

INSPECTION

ASSEMBl
Y
AND

ADJUSTMENT

INSTAllATION
BR
lO

BR
1O

BR
lO

BR
ll

BR
12

BR
12

BR
13

BR
13

BR
13

BR
14

BR
14

BR
14

BR
16

BR
16

BR
17

BR
17

BR
IB

b

i
t

I
Fulcrum

pin

2
Return

spring

3
Pedal

bushings

4
Clevis

pin

5
Brake

pedal
5

BR766
BR657

Fig
BR
5
Broke

pedal
mounting

2
Remove
cotter

pin
from
clevis

pin
and

separate
pedal
from
Master

Vac

push
rod

3
Remove
fulcrum

pin
and

pedal
INSPECTION
Fig
BR
6
Broke

pedal

INSTALLATION

Check
brake

pedal
for
the

following

items

servicing
as

necessary

I
Check

pedal
bushing
for

wear

deformation
or

damage

2
Check

pedal
shaft

sleeve
for
wear

or
roughness

3
Check
for

bent
brake

pedal

4

Check
for

fatigued
return

spring
Note
Loosen
fulcnun

pin
clockwise
Install
b
rake

pedal
in
the
reverse

sequence
of
removal

paying
attention

to
the

following
instructions

1
Insert
fulcrum

pin
into
hole
in

brake

pedal
and
bracket
from

right

side

2
Install
clevis

pin
from
left
hand

side

BA
4

3

Hook
return

spring
to

brake

pedal

assembly
from
accelerator

pedal
side

4

Apply
a

coating
of
recommended

multipurpose
grease
to
the
inner
and

outer
faces
of

pedal
bushing
clevis

pin
and
hooks

of
return

spring

Charge
the
clearances
in

bushings
with

grease

Grease

m
n

L

g

U

BR298

Fig
BH

7
Greasing
place

5

lnstali
brake

lamp
switch

6

Adjust
the
brake

pedal
after
in

stallation
Refer
to
the

instructions

under

Adjustment

Tightening
torque

Fulcrum

pin

1

9
to
2
4

kg
m

14to

17ft
ib

MASTER
CYLINDER

The
diameter
of

cylinder
is
19
05

mm

y
in
for

all
models

The
tandem

master

cylinder
contains
two
fluid

reservoirs
which

connect
the

front
and

rear
brake

lines

independently

Braking
force
is

constantly
main

tained
when
failure
occurs
in
either

the
front
brake

system
or

the
rear

brake

system
Failure
in
the

front

brake

system
will
leave
the

rear
brake

still

operative
or

failure
in
the
rear

brake

system
will
leave
the
front
brake

system
still

operative

The
reservoir
is

eq
ui

pped
with
a

retention

cap

To
remove
this

cap
proceed
as

follows

I
Tum
retention

ring
fully
in
the

REMOVE
direction

2
Pull
out
retention

cap
Brake

System

To
install
it

proceed
as
follows

I
Turn
retention

ring
used
in
the

retention

cap
fully
in

the
REMOVE

direction

Tokico

@

1tr

I

I

I
j
1

Nabco

BR926
2

Align
the

projection
in
retention

cap
with
the
slit
in
the
reservoir
tank

and

push
retention

cap
in
the
tank

3
Turn
retention

ring
fully
in
the

TIGHTEN
direction

00
CD
1
Reservoir

cap

2

Reservoir
tank

3
Secondary

piston
return

5pring

4

Stopper
screw

5

Secondary

piston

6
Primary

piston
return

spring

7
Primary

piston

Fig
BR
B
Sectional
view

of
tandem
master

cylinder

o

BR658

Fig
BR
9
Master

cylinder

BR
5
REMOVAL

1
Disconnect

front
and
rear

brake

tubes
from

master

cylinder

Notes

a
When

removing
brake
tubes
use

Flare
Nut

Torque
Wrench

GG94310000

Never

use

open
end
or

adjustable

wrench

b
When

disconnecting
brake
tubes
be

sure
to
use
a

container
to
receive

draining
brake
flnid
Use
of

rags
is

also

suggested
to

keep
adjacent

parts
and
area
clean

2
Remove
master

cylinder
securing

nut
Then
master

cylinder
can
be

taken

out

DISASSEMBLY

AND

ASSEMBLY

1

00
11I

1

Reservoir

cap

2
Oil
mter

3
Oil

reservoir

4

Packing

5
Valve

cap
Brake

System

00

oC
1

O

b
0
1

r
r

L

BA927

6

Secondary
piston

stopper

7

Bleeder
screw

8

Secondary
return

spring

9

Secondary
piston

10

Primary
return

spring
11

Primary
piston

12
Piston

stopper

13
Piston

stopper
ring

1
Remove
reservoir

cap
and
filter

and
drain
out
brake
fluid

2

Pry
off

stopper
ring
using
a

screwdriver

3
Remove

stopper
screw
and

take

out

stopper
primary
piston
assembly

spring
and

secondary
piston

assembly

in
the

order
shown

Note
Discard

piston
cup
if
it
is
re

moved
from

piston
sembly
and

use
a
new

one

4

Unscrew

plugs
to

gain
access
to

check

valve
for

disassembling

Note
Never
detach
reservoir
tank
U

it
is
removed
for

any
reason
dis

canI
it

and
install
a
new
one

S
Assemble
master

cylinder
in

the

reverse

sequence
of

disassembly
pay

ing
particular
attention
to
the

follow

ing
notes
Fig
BR
10
Master

cylinder

Tightening
torque

Valve

cap

T
okico

8

t09

kg
m

S8
to
6S
ft
Ib

Nabco

2
5
to
3
S

kg
m

18
to
2S

ft
Ib

Bleeder

0
7

to
0

9

kg
m

S
to

7
ft
lb

Notes

a

Replace
gaskets
and

packings
with

new
ones

b

Apply
brake
fluid
or
rubber

grease

to

sliding
contact
surfaces
of

parts

to
facilitate

assembly
of
master

cylinder

c
The
blllke
master

cylinder
is
avail

able
in
both
NABCO
make
and

TOKlCO
make
There
is
no
inter

changeability
of

repair
kits
or
com

ponent
parts
between
NABCO
and

TOKlCO
JIIlkes
When

replacing

the

repair
kit

or

component

parts

BR
6
ascertain
the
brand
of
the
brake

master

cylinder
body
Be

sure
to

use

parts
of
the

same
make
as
the

former
ones

INSPECTION

Thoroughly
clean
all

parts
in

a

suitable
solvent
and
check
for
WOol
or

damaged
parts
Replace
any

part
that

is

faulty

Note
Do

not
clean
robber

parts
with

minerai
oil
since
this
will
be
the

sure

way
of

deteriolllting
parts
Use

brake
fluid
or
alcohoL
When

alco

hol
is
used
for

leaning
these

parts

do
not

immerse
them

in
it

longer

than
30

seconds
After

parts
are

cIeaned

dry
with

compressed
air

I
Check

cylinder
and

position
for

evidence
of
abnonnaI

wear
or

damage

Replace
if
found

faulty

2

Check

piston
to

cylinder
clear

ance
If
it
is

more
than

O
IS

mm

0
OOS9
in

replace
either

piston
or

cylinder

Master

cylinder
inner
diameter

19
0S
mm
Yoin

3
Check
for
weakened

fatigued
or

damaged
springs
and

replace
if
neces

sary

4
When
master

cylioder
is

disassem

bled
be
sure
to

discard

cups
and

valves

Replace

any
other

part
which

shows

evidence
of
deformation
wear

or

damage

S

Replace
damaged
oil
reservoirs

and

caps

INSTALLATION

Install
master

cylinder
in
the

re

verse

sequence
of
removal

Bleed
air

out
of
master

cylinder
by

loosening
bleeder
screw
after
it
is

installed
in

its

original
position

Tightening
torque

Brake
master

cylinder

attaching

nut

0
8
to
1
1

kg
m

6
to
8
ft
Ib

Brake
tube
connector

I
S
to
1
8

kg
m

II

to
13
ft
Ib

BRAKE

LINE
Brake

System

Detail
A

Detail
B

Detail
C
Detail
D

Detail
E

Detail
of
Detail

G

Detail
R

Detail
1

BR
7
Detail

K

Detail
L

BA767

Fig
BR
ll
Brake
line

REMOVAL

1

Removing
flare

nuts
on

both
ends

and

clips
effects
the

removal
of

brake

tube
and
brake
hose

2

Rear
brake
hose
can
be

removed

by
disconnecting
the
tube
and
then

turning
round
the
hose

Note
When

removing
brake
tubes
and

hoses

use
Flare
Nut

Torque

Wrench
GG943IOOOO

Never
use

an

OpeD
end

or
an

adjust

able
wrench

INSPECTION

1
Examine

all
hoses
for
swell

rubbing
marks
or
ozone
cracking

re

placing
those

found
with

any
of
above

badly
beyond
use
Also

inspect
end

fittings
and
be
sure
that
no
fluid
leak

through
staked
end

has
taken

place

replace
if

necessary
Hose

with

badly

rusted

fitting
should

also
be

replaced

with
a
new
one

2

Clean
all
tubes

to
remove
dust

and

dirt
with

isopropyl
alcohol

check

ing
for

collapse
wear

cracking
swell

or

rusting
Replace
if
foun
d

with

any

of
wove
Use
care
not
to

damage

brake
tubes

while

operation

Check
if
tubes

are

clamped
secure

ly

Mter
all

brake
lines

have
been

installed

retighten
aU
connections
if

necessary
to

assist
in

obtaining
correct

torque
In

retightening
at
front
wheel

cylinder
first
remove
hose

clamp
and

loosen
flare
nut
on

opposite
side
to

avoid

twisting
hose

Hold

pedal
as
far
downward
as

possible
80

kg
176
lb
or
more

examining
evidence
as
to
whether
fluid

is

leaking
through
brake

lines
or

con

nections

Leakage
in

any
manner
can

not
be

permitted
here
In

case
fluid

leaks

tightening
to

specified
torque

tighten
additionally
up
to
2
5

kg
m

J
8
ft
lb
Under

no
circumstances

should
not

be

tightened
over
2
5

kg
m

18
ft
Ib

torque
since
this

elongates

end

fitting
making
it

impossible
to

reuse
brake
tube

Under
no
circumstances
should
rear

brake
hose
and
3

way
connector
be

retightened
over

specified
torques
In
Brake

System

stead

replace

copper
washer
with
a

new
one

after

checking
for

sign
of

damage
on

seating
surface
Never
reuse

an
old

copper
washer

INSTALLATION

Brake
hose

Front
brake

hose

In

installing
brake
hose
first

jack

up
vehicle

to
take
off
the

weight
of

vehicle
from

wheels
so
that

suspension

is
in
rebound

Steering
wheel
should

also
be

kept
in

straight
ahead

position

To
connect
brake

line
first

connect

brake

hose
to
wheel

cylinder
with
the

specified
torque

Tightening
torque

1
7
to
2

0

kg
m

12
to

14
ft
Ib

Then
secure

brake
hose
to
the

bracket
with
lock

plate
so
as
not
to

twist
or

abnormally
bend
the
hose

Note

After

connecting
brake
hose

at

both
eiuIs

pay
keen
attention
not

to
twist
the
hose
when
additional

tightening
is

required

Fig
BR

12
Front
brake

hose

Rear

brake
hose

First
secure
rear
brake
hose
to

3

way
connector
on
rear
axle
case
to

the

specifications
Mter

connecting

hose
do
not

tighten
it

at
3

way

connector

additionally
since
this

oper

ation

causes
hose
to
be
twisted

Tightening

torque

I
7

to
2
0

kg
m

12
to
14
ft
Ib

BR
8
Fig
BR
13
Rear
brake
ho
e

After
brake
hose
has
been
installed

check

to
be

sure
that
there
is

enough

clearance
between
hose
and

adjacent

parts
to
avoid
contact
with
other
ones

The
check
should
be
carried
out
while

moving
wheel

up
and
down

through
its

full

stroke
and

rotating
steering
wheel

between
two
extreme
lock

positions

The
wow
clearance
must
be
as

follows

Hose

to

rotating
or

mOving
parts

such
as
tire
and

rim

40
mm
1
57
in

and
more

Hose
to

stationary

part

2S

mm
0

98
in
and
more

In

case
that
the

above
clearance

cannot
be
obtained
it

may
be
caused

by
the
hose

twisted

Accordingly

carry
out
the
correction
with
hose

connection

again
following
the
above

instructions

Brake
tube

In

installing
a
brake
tube
use
care

to
locate
its

end

squarely
on

mating

seat

noting
the
fact
that
nut
can
be

turned

freely
by
a

light
finger
twist

Then

tighten
to
correct

torque
with
a

Brake

Pipe
Torque
Wrench

GG943
10000

Tightening
torque
Flare
nut

1
5
to
1

8

kg
m

11
to

13
ft
Ib

In
addition
care
should
also
be

exercised
to
avoid

damaging
or
col

lapsing
brake
tube

during
operation

Be
sure
to
make

enough
clearance

between
all
tubes
and
other

adjacent

parts
to
avoid
contact

In

installing
tube

through
hood

ledge

grommet
be
sure
to

position
it

at
the

center
of

grommet

After

connecting
brake
tube
be

sure
to

check
the
clearance
to

prevent

from

damage
The
clearance
at

the

following
portions
must
be

specified

distance
or

more

Tube
to

body
panel
and

frame

Over
5

mm
0
20
in

Tube

to
edge
of
each

panel

Over
10
mm
0
39

in

Tube
to
tube

Loop
pitch

OVer
5
mm
0
20
in

Between
front
tube
and

rear
tube

Over
9

mOl
0
35

in

Tube
to

moving
parts

Over
10
mm
0
39
in

Loop
tube
to

hood

ledge

panel

Over
10

mm
0
39
in

Notes

a
Brake
tubes
are

shaped
at

factory

to
secure

specified
clearance
and

may
not

require
reshaping
Discard

if

they
call
for
excessive

reshaping

b
In

reshaping
a
brake
tube
take
care

to
avoid

damaging
galvanization
or

collapsing
section

Mter
brake
lines
have
been

asssem

bled
check
to
make
sure
that
all

fittings
and
flare
nu
Is
ale

lightened
to

correct

torques

Tightenint
torque

Brake
tube
to
connector

I
Ston

kg
m

II
to

13
ft
Ib

Brake
tube
to
brake
hose

1
7
to

2
0

kg
m

12
to
14
ft
lb

Connector
and

clip
fixing
bolt

O
3S
to
O
4S

kg
m

2
5

to
3
3

ft
lb

3

way
connector

fixing
bolt

on
rear

axle
case

0
8
to
1
1

kg
m

6
to
8
ft
lb

N
L
S
V

DESCRIPTION

The

Nissan
Load

Sensing
Valve

N
L
S
V

serves
to

change
braking

power
of
the

rear
wheels
in

response

to

changes
in
the
load
and
fluid

pressure
improving
braking
stability

and

shortening

stopping
distances
Brake

System

The
N
L
S
V

is
installed
on
the

frame

being
inclined
at
10

degrees
A
summary
of

the
N

L
S
v

operation
is

given
in

Figures
BR
14

and
BR
15

r
Master

cylinder
TI
II

I

y

1

J

I

l
Attaching
angle

D

Wheel

cylinder

BR928

Fig
BR
14
Construction

of
N
L
S
V

Performance
curve
of
brake
fluid

pressure
is
as

follows

0

S

c
A

0

C

o

l
0
oadea

U1U

Front
wheel

cylinder

fluid

pressure
BR769

Perfonnance
curve

of
fluid

pressure
Fig
BR
15

N
L
S
V
TEST

the

following
occurs

When
rear
wheels
lock

stopping

distance
is
shorter
than
13
1

m
43

0

ft
whether
loaded
or
unloaded

Stopping
distance
should
be

measured

from
the

place
where
the
brake

pedal

is

first

applied
to
the

place
the
vehicle

actually

stops
Front
wheels
lock

simultaneously
with
or
ahead
of
rear

wheels
Operating
test

The

test
should
be
conducted
under

these
conditions

Drive
a
vehicle
with

pay
load
and

then
with

only
driver
on

a

dry
flat

concrete
or

asphalt
road

applying
the

brake
suddenly
at
40
km

h
25
MPH

N
L
S
V
is

functioning
normally
if

BR
9