1977 DATSUN PICK-UP Service Manual

Manual
Transmission

I

TROUBLE
DIAGNOSES
AND
CORREGTIONS

Condition

Difficult
to

intel11lesh
gears

Causes
Jor
difficu
t

gear
shifting
are
classi

fied
to
troubles

concerning
control

system

and
transniissioo
When

gear
shift
lever
is

heavy
and
it
is
difficult
to
shift

gears
clutch

disengagement
may
also
be
unsmooth
First

make
sure
that

clutch

operates
correctly

and

inspect
transmissi
o

Gear
slips
out
of
mesh

In
most
cases
this
trouble
occurs
when

interlock
b
all
check
ball
and

or
spring
is

worn
or
weakened
or

when
control

system

is

faulty
In
this
case
the

trouble
cannot
be

corrected

by
replacing
gears
and
therefore

trouble

shooting
must
be

carried
out

care

fully
It
should
also
be

noted
that

gear
slips

out

of
mesh
due
to
vibration

generated
by

weakened
fron
t
and
rear

engine
mounts

Noise

When
noise
occurs
with

engine
idling
and

ceases
when

clutch
is

disengaged
or
when

noise
occurs
while

shifting
gears
it
is

an

indicati90
that
th
e
noise
is

from
transmis

sion

t
Transmission

may
fa
ule

during
engine

idling

Check
air

fuel
mixture
and

ignition

timing

After
above

procedure
readjust
engine

idling
Probable

cause

Worn

gear
shaft
and
or

bearing

Insufficient

operating
stroke
due
to
worn
or

loose
sliding

part

Faulty
or

damaged
synchronizer

Worn
interlock
ball

Worn
check
ball

and
or

weakened
or
broken

spring

Wom
fork
rod
ball

groove

Wom
or
damaged
bearing

Worn
or

damaged
gear

Insufficient
or

improper
lubricant

Oil

leaking
due

to

faulty
oil

seal
or

sealant

clogged

breather
etc

Worn

bearing

High
humming
occurs
at
a

high
speed

Damaged
bearing
Cyclic
knocking
sound

occurs
also
at
a

19W
speed

Worn

spline

Worn

bushing

j

MT
23
Corrective
action

Replace

pair
or
replace

Replace

Replace

Replace

Replace

Replace

Replace

Add
oil
or

replace

with

designated
oil

Clean
Of

replace

Replace

Replace

Replace

Replace

No
Tool
number

tool
name

ST23540000

Fork
rod

pin

punch

2
ST22360002

Drift
C

3
ST23800000

Transmission

adapter

4
ST238
10001

Setting
plate

adapter
Manual
Transmission

SPECIAL
SERVICE
TOOLS

Description

Unit

mm
in

For
removal
of
fork
rod

retaining
pin

L

i
150
5
91

10
0
39
dia

For

assembly
of
counter
drive

bearing

oOler
dia
32
1
26

inner
dia
23
0
91
SE034

For

assembly
of
main

bearing

480

18
90

outer
dia
44

1
73

inner
dia
31
1
22
SE037

For

setting
adapter
plate
in
a
vise

SE132

74
2

91

MT
24
For

use

on
Reference

page
or

Figure
No

All

Fig
MT
15

models

llBT
M

Fig
MT
44

FS5W

63A

All

Page
MT
1O

models

71BT
M

Fig
MT
14

Fig
MT
15

Fig
MT
45

Manual
Transmission

No
Tool
number

tool
name
Description

Unit
mm
in
For

use

on
Reference

page
or

Figure
No

5

ST22520000

Wrench

38mm

1
50
in
For
removal
and

assembly
of
mainshaft
nut
71BT
M
Fig
MT46

63A

TIM
Fig
MT47

SE313

6
ST23860000
For
assembly
of
counter

drive

gear
7IBT
M

Fig
MT42

Counter

gear

drift

outer
dia
38
50

inner

dia
33
1
30

SE039

7

KV31100400
For
assembly
of
rnainshaft
countershaft
counte
drive

gear
and
7IBT
M

Fig
MT
37

Transmission
counter
drive

bearing
Fig
MT
39

press
stand
4
8
1
89
75
2
95
Fig
MT44

0

Q
0

J

I

0

TM438

8
STJ0031000
For

replacing
bearing
All

Fig
MT
21

Bearing
puller
models

Fig
MT
23

Fig
MT
25

80

3
15

50
1
97

SE041

MT
25

Manual
Transmission

No
Tool
number

tool
name
Unit
mm
in
Description

9
KV32101330
For
removal
of
mainshaft
end

b

ari
lg
counter
overdrive

gear
and

Bearing
puller
bearing

300
11
81

SE308

MT

26
For

use

on
Reference

page
or

Figure
No

63A

l
fM
Fig
MT
64

FS5W

7IBT
M

DATSUN
PICK
UP

MODEL
620
SERIES

I
NISSAN

I

NISSAN
MOTOR
CO
LTD

TOKYO
JAPAN
SECTION
AT

j

AUTOMATIC
L

TRANSMlsSIO
N

I

I

DESCRIPTION

HYDRAULIC

CONTROL
SYSTEM

REMOVAL
AND
INSTALLATION

MAJOR
REPAIR

OPERATION

TROUBLLDIAGNOSES
AND

ADJUSTMENT

SERVICE
DATA
AND

SPECIFICATIONS

I
SPECIAL
SERVICE

TOOLS
At
2

AT
4

AT

33

AT
36

AHD

AT

59

AT

62

The
model
3N7l
B
automatic

trans

mission
is

a

fully
automatic

unit
con

sisting
primarily
of
3
element

hydrau

lic

torque
converter
and

two

planetary

gear
sets
Two

multiple
disc
clutches
a

multiple
disc
brake
a
band
brake
and

a
one

way

sprag
clutch

provide
the

friction
elements

required
to
obtain

the
desir
d
function
of
lhe
two

plane

tary
gear
sets

The

two

planetary
gear
sets

give

three
forward
ratios

and
one
reverse

Changing
of
the

gear
ratios
is

fully

automatic
in
relation
to
vehicle

speed

and

engine
torque
input
V

chide

speed

and

engine
manifold
vacuum

signals

are

constantly
fed
to
the

transmission

to

provide
the

proper
gear
ralio
for

maximum

efficiency
and

performance

at
all
throttle

openings

The
model
3N71
B
has
six

selector

1

9sition
LP
R

N
D
2
1

I

Park

position
positively
locks

the

output
shaft
to

the
transmission

case

by
means
of
a

locking

pawl
to

prevent
the
vehicle
from

rolling
in

either
direction

This

position
should
be

selected

whenever
the
driver
leaves
Ihe
vehicle

Thc

engine

may
be
slarted
in
Park

position

R
Reverse

range
enables
the

vehicle
to
be

operated
in

a
reverse

direction

N
Neutral

position
enables
the

engine
to

be
started
and
run

without

driving
the
vehicle

0
Drive

range
is
used

for
all

normal

driving
conditions

Drive

range
has
three

gear
ratios

from
the

starting
ratio

to
direct
drive
Automatic
Transmission

DESCRIPTION

2

2

range
provides

performance

for

driving
on

slippery
surfaces

2

range
can
also
be
used
for

engine

braking

2

range
can
be
selected
at

any

vehicle

speed
and

prevents
the
trans

mission
from

shifting
out
of

second

gear

I
I

range
can
be

selected
at

any
vehicle

speed
and
the
transmission

will
shift
to

second

gear
and
remain
in

second
until
v

hicle

speed
is
reduced

10

approximately
40
to
50

kmfh
25

to
30
MPH

I

range
position
prevents
the

transmission
from

shifting
out
of
low

gear
This
is

particularly
beneficial
for

maintaining
maximum

engin
braking

when

continuous
low

gear
operation
is

desirable

The

torque
converter

assembly
is
of

welded

construction
and
can

nOlbe

disassembled

for
service

FLUID
RECOMMENDATION

Use
automatic
transmission

fluid

having
DEXRON
identifications

only
in
the
3N71
B

automatic
transmis

sion

IDENTIFICATioN
NUMBER

Stamped

position

The

plate
is

attached
to
the

right

hand

side
of
transmission
case

as

shown
io

Figure
AT

I

AT
2
AT344

Fig
AT
I

Identification
number

Identification

of
number

Arrangements

See
below

Model
code

JAPAN

AUTOMATIC

0J
TRANSMISSION
CO
LTD

I
MODEL
X2402

I

J
I
NO

4912345

I

Unit
number

Number

designation

4
9

I

234
5

L

Serial

production

number
for

the
month

Month
of

production

X

Oct
Y

Nov
Z
Dec

last

figure
denoting

the

year
A
D

Automatic
Transmission

o
J

II

IIlI

r
I
r

A

T288

I
Transmission
ca
e

2
Oil

pump

3
Front
clutch

4
Band
brake

5

Rear
clutch

6
Front

planetary
gear

7
Rear

planetary
gear

8
One

way
clutch

9
Low

Rever5e
brake

10
Oil
distributor
II

Governor

12

Output
shaft

13
Rear
extension

14
Oil

pan

IS
Control
valve

16

Input
Jlihafl

17

Torque
converter

t
8
Converter

housing

19
Drive

plate
Tightening

torque
T
of

bolts
and
nuts

kg
m

ft
lb

@
T

4105
29

10
36

@
T

141016
10110116

@
T
4
5

to
5
5
33
1040

@
T

0
6100

8
4
106

@
T
0
5
to
0
7
4
10
5

T

2
0102
5
14
10
18

@
T
1
3
10
1

8
9
10
13

T

0

55100
75
4
105

CD
T
0
25
10
0

35
2
to
3

Fig
AT
2
Cross
sectional
view
of
3N71B
automatic
transmission

AT3

Automatic
Transmission

HYDRAULIC

CONTROL
SYSTEM

FUNCTIONS
OF
HYDRAULIC
CONTROL

UNIT
AND
VALVES

OIL

PUMP

MANUAL
LINKAGE

VACUUM
DIAPHRAGM

DOWNSHIFT
SOLENOID

GOVERNOR
VALVE

CONTROL
VALVE

ASSEMBLY

HYDRAULIC
SYSTEM
AND

MECHANICAL
OPERATION

FUNCTIONS
OF

HYDRAULIC
CONTROL

UNIT
AND
VALVES

The

hydraulic
control

system
con
CONTENTS

P
RANGE
PAR

K

R

RANGE
REVERSE

N

RANGE

NEUTRAL

D1
RANGE
LOW
GEAR

D2
RANGE

2ND
GEAR

D3
RANGE
TOP
GEAR

D
RANGE
KICK

DOWN

2

RANGE
2ND
GEAR

t
RANGE
LOW
GEAR

12
RANGE
2ND

GEAR
AT
4

AT
4

AT
4

AT
5

AT
5

AT
5

AT

6

AT13

tains

an
oil

pump
for

packing
p
oil

from
the
oil

pan
through
the
oil

strainer
A

shift
control
is

provided
by

two

centrifugally
operated
hydraulic

governors
on
the

output
shaft

vacuum

control

diaphragm
and
downshift
AT14

AT16

AT18

AT

20

AT

22

AT

24

AT

26

AT

28

AT

30

AT

32

solenoid

These

parts
work
in

conjunc

tion

with
valves

in
the
valve

body

assembly
located
in

the
base
of
the

transmission
The
valves

regulate
oil

pressure
and
direct
it

to

appropriate

transmission

components

Oil

pump
I
I

Control
valve
I

Torque
converter

1

I
I

I

Manual

linkage
Front
clutch

Vacuum

diaphragm
I

Rear
clutch

I
Low
and

reverse
brake

Downshift
solenoid

I
Band
brake

Governor
valve

r
I
Lubrication

OIL
PUMP

The
oil

pump
is

the
source
of

control
medium
i

e
oil
for
the

control

system

The

oil

pump
is

of
an
internal

involute

gear
type
The
drive
sleeve
is
a

part
of
the

torque
converter

pump

impeller
and

serves
to
drive
the

pump

inner

gear
with
the
drive
sleeve
direct

ly
coupled
with
the

engine
operation

The
oil
flows

through
the

following

route

Oil

pan
Oil

strainer
bottom
of
the

control
valve

Control
valve
lower

body
suction

port
Transmission

case

suction

port

Pump
housing
suction

port
Pump
gear

space
Pump
housing
delivery
port
Transmission

case

delivery

port
Lower

body

delivery

port
Control
valve
line

pressure
circuit

AT071

I
Housin
4

Inner

gear

2

Cover

5
Crescent

3
Ouler

gear

Fig
AT

3
Oil

pump

AT
4
MANUAL

LINKAGE

The
hand

lever
motion
the
hand

lever
is
localed
in

the
driver
s

compart

ment

mechanically
transmitted
from

lhe
remote

control

linkage
is

further

transmitted
to

the
inner

manual
lever

in
the
transmission

case
from
the

range

selector
lever
in
the

right
center

par

tion
of
the
transmission

case

through

the

manual
shaft
The
inner

manual

lever
is

thereby
turned

A

pin
installed
on

the
bottom
of

the
inner

manual
lever

slides
rhe
manu

al
valve

spool
of
the

conlrol
valve
thus

positioning
the

spool
opposite
rhe

appropriate
select

posilion

The

parking
rod

pin
is

held
in
rhe

groove
on
the

top
of
Ihe
inner

manual