brakes DATSUN PICK-UP 1977 Service Manual

Page 312 of 537


Automatic
Transmission

TROUBLE

DIAGNOSIS
AND
ADJUSTMENT

INSPECTION
AND
ADJUSTMENT

BEFORE

TRQUBLE
DIAGNOSIS

TESTING

INSTRUMENT
FOR

INSPECTION

CHECKING
OIL

LEVEL

INSPECTION
AND
REPAIR
OF

OIL
EAKAGE

CHECKING

ENGINE
IDLING

REVOLUTION

CHECKING
AND
ADJUSTING

KICKDOWN

SWITCH
AND

DqWNSHIFT
SOLENOID

N
J
J
CII
Q

t
L
8li
p

JYSTMs
T
OF

MANUAL
LINKAGE

CHECKING
AND

ADJUSTING

INHIBITOR

SWITCH

STALL
TEST

STALL
TEST

PROCEDURES

JUDGEMENT

Since
most
automatic

transmission

troubles

can
be

repaired

by
simple

adjustment
do
not
disassemble
im

mediately

Firstly

inspect
and

adjust
the
auto

matic
transmission

in

place
utilizing

the
Trouble

Shooting
Chart

If
the
trouble
can

not
be
solved

by

this

procedure
remove
and
disas

semble

the
automatic
transmission

It

is

advisable
to
check

overhaul
and

repair
each

part
in
the

order
listed
in

the
Trouble

Shooting
Chart

I
In
the
Trouble

Shooting
Chart

the

diagnosis
items

are

arranged
ac

cording
to

difficulty
from

easy
to

difficult
therefore

please
follow
these

items
The
transmission
should
not

be

removed
unless

necessary

2
Tests
and

adjustments
should
be

made
on
the
basis
of
standard
values

and

the
data

should
be
recorded

INSPECTION

AND

ADJUSTMENT

BEFORE

TROUBLE
DIAGNOSIS

TESTING
INSTRUMENT
FOR

INSPECTION

I

Engine
tachometer

2
Vacuum

gauge
ROAD
TEST

VEHICLE
SPEED

AT
GEAR

SHIFT

CHECKING
SPEED
CHANGING

CONDITION

CHECKING
ITEMS
DURING
SPEED

CHANGE

SHIFT
SCHEDULE

LINE

PRESSURE
TEST

LINE

PRESSURE

governor
feed

pressure

JUDGEMENT
IN

MEASURING
LINE

PRESSURE

At
49

TR6
uBLE
SHOOTINC
CHART

INSPECTING
ITEMS

TROUBLE

SHOOTING
CHART
FOR

3N71B

AUTOMATIC
TRANSMISSION

TROUBLE

SHOOTING
GUIDE
FOR

3N71B

AUTOMATIC
TRANSMISSION
CONTENTS

AT
4B

AT
48

AT
4B

AT

49

AT
49

AT
49

AT
49

AT
50

AT

50

AT
50

3
Oil

pressure
gauge

It
is
convenient

to
install
these

instruments
in
a

way
that
allows
meas

urements
to
be
made
from
the
driver
s

seat

CHECKING
OIL
LEVEL

In

checking
the
automatic
transmis

sion

the
o
illevel
and
the
condition
of

oil
around
the
oil
level

gauge
should
be

examined
This
is

an

easy
and
effective

trouble

shooting

procedure
since

some

changes
in
oil
condition

are
often

linked
with

developed
troubles

For
instance

Lack
of
oil
causes

faulty
operation

by
making
the
clutches
and

brakes

slip
resulting
in

severe
wear

This
is
because
the
oil

pump
sucks

air

causing
oil

foaming
thus

rapidly

deteriorating
the
oil

quality
and

pro

ducing
sludge
and

varnish

Excessive
oil
is

also
bad
because
of

oil

foaming
caused

by
the

gears

stirring

up
the
oil

During
high
speed

driving

excessive

oil
in

the

transmission
often

blows
out

from
the
breather

Measuring
011
level

To
check
the
fluid
level
start
the

engine
and
run
it
until
normal

operat

T
AO
AT
51

AT
51

AT

52

AT
52

AT
52

AT

52

AT

53

AT
3

AT

53

AT

53

AT

54

AT
57

ing
temperatures
o

temperature
SO

to
800C

122
to
l760F

Approxi

mately
ten

minute
of

operation
will

raise
the

temperature
to
this

range

and

engine

idling
conditions

are
stabi

lized
Then

apply
the
brakes
and

move
the

transmission
shift
lever

through
all
drive

positions
and

place
it

in

park
P

position
In

this

inspec

tion
the
car
must
be

placed
on
a
level

surface

The
amount
of
the
oil
varies

with

the

temperature
As
a
rule
the
oil
level

must
be
measured
after
its

temper

ture
becomes

sufficiently
high

1

Fill
the
oil
to

the
line
H
The

difference
of

capacities
between
both

H
and
L
is

approximately
0
4

liter
Ji
V
S

p
Y

Imp
pl
and

therefore
do

not
to
fill

beyond
the

line

H

2
When

topping
up
and

changing

oil
care
should
be
taken
to

prevent

mixing
the
oil
with
dust
and
water

InspectIng
011

condition

The
condition
of

oil

sticking
to
the

level

gauge
indicates
whether
to
over

haul
and

repair
the
transmission

or

look
for
the

faulty

part

If
the
oil
has
deteriorated
to
a

varnish
ike

quality
it

causes
the

con

trol
valve
to
stick
Blackened
oil
indi

cates
a
burned
clutch
brake
band
etc

Page 318 of 537


Automatic

Transmission

TROUBLE
SHOOTING
CHART
FOR
3N718
AUTOMATIC
TRANSMISSION

The
number
shown
beluw

indicates
the

sequence
in

which
the

checks
should
be
taken

up

Trouble
ABeD

EFGHIIJKL
MNOP

tnnqr
stuv

wxy

ngine
does
not
start
in
N
P

ranges
2

3
1

Engine
starts
in

other

range
than
N

and

P
1
2

Sharp
shock
in

shifting
from
N

to

0

range

Vehicle
will
not

run
in
D

range
bul

I

TUns
in
2u
l
and
R

ranges
2
4

@

3

5
6
3
7

@
@
2
1
3

Vehicle

will
not

run
in
0
1

2

ranges
bul
runs
in
R

range
1
2

Clutch

slips
Very
poor
acceleration
4

Vehicle
will
nol
run
in
R

range
bul

runs
in
0

2
and
I

r

nges
1
2

Iukh

slips
Very
poor
acceleration
3

5
6
4

@@
1
@
@

Vehicle
will
not
run
in

any
range
1
2
3
5
6
4
1
@
@

Clutches

or
brakes

slip
somewhat

1
2
6

I
3
5
7
4

@@

in

starting

Vehicle
runs
in
N

range
I
3
2

Maximum

speed
not
allained

1
2
4
5
7
6
3
8

OO
I@

Acceleration

poor

Vehicle
braked

by
Ihrowing
Icver
inlo
3

2
1

@

I
@

R

range

I

Excessive

creep
1

No

creep
al

all
I
2
3
5
4

@@

@
1

Failure
10

dumge
gear
from
2nd

I
2
3
5
6
8
7
4

@
@

to
3rd

Failure

tllchJllgC
gear
from
1
1

1
2
3
5
6
8
7
4

@
@
@

to
2ud

Too

high
a

gear
change
poinl
from

I

sC
to
2nd
from

2nd
to
1
2
3
5
6
4
1

3rd

Gear

change
directly
from

lsl
to

2
4

3
1
@

@

rd
occurs

AT

54

Page 377 of 537


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

Page 378 of 537


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

Page 397 of 537


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

Page 398 of 537


Condition

Brake
chatters

Brake

squeals

Pedal

pulsates

Brakes
fade

Brakes

drag

Unbalanced
brakes
Brake

System

Probable
cause

Groove

or
out
of

round
brake
drum

Loose

or
bent

brake

disc

Distorted
brake
shoes

or

pads

Grease
or
brake
fluid
on

linings

Dirty
or
scored
brake

drums

Distorted
brake
shoes
or
bent

support
plate

Weak
or
broken
brake
shoe

retaining
spring

or

return

spring

Glazed
or
contaminated
brake

lining

Out
of

round
or
off
center
drum

Brake
fluid
has
too
low

boiling
point

Use
of

improper
linings
or
brake

linings
are

contaminated

Brake
drums
are
out
of
round

Hydraulic
connections
master

cylinder
and

wheel

cylinders
are

corroded
or

damaged

Bleed
screw
is

open

Pedal

linkage
is

binding
or

push
rod

adjust

ment
is
too

long

Master

cylinder
compensator
part
is
ob

structed

Seized
master

cylinder
piston

Poor
shoe
condition

Poor

wheel
cylinder
condition

Deformation
of

piston
cups

Hand
brake
will
not
return

Clogged
master

cylinder
return

port

Improper
tire
inflation

Improper
adjustment
of
shoe

to
drum
clear

anee

Grease
oil
mud
or
water
on

linings
or

pads

Mud
in

brake
drum

Deterioration
of

linings
or

pads

Excessive
wear
of

linings
or

pads

BR
23
Corrective
action

Grind
or

replace
as

required

Tighten

support
plate
bolts
to

specified

torque
or

replace
plate

Replace
as

necessary

Replace
linings

Blowout

assembly
with

compressed
air
or

refinish
drum

Replace
faulty
unit

Replace
if

faulty

Cam

ground
lining
to
eliminate

glaze
If

it

doesn
t

replace
linings

Turn

drum
or

replace
as
necessary

Drain
and
fill

system
with

approved
fluid

Replace
linings

Repair
or

replace
as
necessary

Repair
as
necessary

Close
screw
and
bleed

system

Lubricate

linkage
check

pedal
return

spring

for
condition
and

adjust
push
rod

as
neces

sary

Blowout

foreign
matter
with

compressed

air

Disassemble
master

cylinder
and

replace

piston
Bleed

system

Clean
and

repair

Repair
or

replace

Replace

Check
and

repair

Clean

Inflate
to
correct

pressure

Readjust

Clean
brake

mechanism
and
check
for
cause

of

problem
Replace
linings
or

pads

Clean

Replace

Replace