1973 DATSUN B110 Service Repair Manual

AUTOMATIC
TRANSMISSION

HYDRAULIC
SYSTEM
AND

MECHANICAL
OPERATION

The

operating
system
of
oil

pres

sure
in
each

range
is

described
below

The
oil

pressure
in
each
circuit

shown
in

the
illustration
is
classified
as

follows

according
to
the
function

The
numerals

show
the
circuit

num

bers

Pressure

source
of

the
line
7

Operating
line

pressure
for

friction

elements

I
2
3
4
5
6

8
9
10
II

12

Auxiliary
line

pressure
13

Pressure
of

throttle

system

16
17

18
19

Others
14
15
t

AT106

Fig
AT
22
ld

Jltification
of
oil

channels
in
case

front

fac
e

Discharge
hole
of
oil

pump
7

Torque
c

nver

pre
ure

14
co

t
Re
r

lutch

pressure
l

Front
clutch

pres5ure
II

I

c
Suction
hole

of

t
o

ump

lUlJJl
0
o

f

Governor

Dl5charge
hol
of
011

pUf
lP
7

pressure
15

I

II

nl

1F
Jl

r
Torque
converter
o

L
U

pres
ure
14

It
0
Servo
release
i
I

prc
sUre
IO

Rear
clutch

Servo

L

i

pres
ure

I

0

6
tightening
19

iressu
9
01

Front

clutch

rJj
low

reverse

pressure
II
0

C

lrv
brake

pressure

Suction
hole
of
oil

pump
s

6od
OJ
12

Governor
feed

pressure
I

ATlOS
AT101

Fig
AT
21

Identification
of
oil

channels
in
oil

pu
mp
Fig
AT
23

Identification
of
oil

channels
in
case

face

AT
13

1

range
Park

The

operation
of
clutches
and
band

are

functionally

quite
the

same
as
in

Neutral

In

parking
however

as
the

parking

pawl
meshes
in
a

gear
whkh
is

splined

to
the

output
shaft
the

output
shaft
is

mechanically
locked
from

rotating

The

oil

discharged
from
the

oil

pump
is
fed
to
each

part
in
a
similar

manner
to
that
of
the

N

range
The

oil

having
the
line

pressure
7
which

has
been

introduced
to

the
manual

valve

V
reaches
the
I
st
2nd

shift

valve

ID
through
the
line

pressure

circuit
5
As

the
1st
2nd

shift

valve
is
forced
to

the

right
hand
side

by
the

spring
the

line

pressure
5
and

I2
actuates
the
low

and
reverse

brake

through
the

groove
Also
the

parking
pawl
engages
with
the
au
tee

teeth

of
the
oil

distributor

by
the

manual
lever

mechanically
locking
the

output
shaft
CHASSIS

Free
Lock

I

l

J

1

ri
r
r0
1

1
J

r

A
T086

Fig
AT
24

Parking
mechanism

Ceo
Clutch
Low
Band
rvo
One

Parking

RanKe

atia
rever
w

y

pawl

Front
RUI

brake
Operation
Release

clutch

Park

Reverse
2
182
on
on

Neutral

01
Low
2
458
on

Drive
02
Second

1
458

03

Top
1
000
on

2
Second
1
458
on
on

12
Second
1458
on

II
Low
2
458
on

AT
14

AUTOMATIC
TRANSMISSION

P

range
Park

Torque
Converter
Low
R

Brek

Brake

Sand

I

1
VOO
O

Solenoid

C

iT
A

q

r
CMo

I

I
U1

t5
I

j

I

T
CQ
r
C

A
uIUi
g
Velv
Bend

i

Servo
1f

a

riealion

11

11111
J
I
2

CID
v

f
0

1

J

fI
I

I
1
O

II

II
CID
Solen
iO

Cow
lift
I

J

II

I

Front

Lubrical
n

v

n
1

j
III

r
I
1

II

Orifice
18

C

tt

J
v

2
5
Mod

I

I

1
1

I

J
5JJ

if
1
@
2nd
3rd

Timing

I

1l
If

m

t

I
r
I

m

II
I
I

I

II

R
vuletor
Valve

II
U
L
J
l2
23

6

@
Menuel

Vel

P
R

N
D

2
I

fl31
i

I

I
I

I

l

I
Throttl

Dr
n

Valy
T

o

u

g

Il

I
d

Not
Jhorklld
Cu
in

lsur
Go
ernor
1
1
litHe

OICondery

Gov
norVelYe
Primary

Gov
no

1

Governor
ur

T
eMU

H

Fig
A
T
25
Oil

pressure
circuit

diagram
P

range
Park

AT
15

R

range
Reverse

In
R

range
the

front
clutch

and

low
and

reverse
brake

are

applied
The

power
flow
is

through
the

input
shaft

front

clutch

connecting
sheU
and
to

the

sun

gear
Clockwise
rotatiun
of
the

sun

gear
causes

counterclockwise

rotation

of
the
rear

planetary
gears

With
the

connecting
drum
held
sta

tionary
by
the
low

and
reverse
brake

the
rear

planetary

gears
rotate
the
rear

internal

gear
and

drive

flange
counter

clockwise
The
rear
drive

flange

splined
to
the

output
shaft
rotates

the

output
shaft
counterclockwise
at
a

reduced

speed
with
an
increase
in

torque
for
reverse

gear

J

When
the

manual
valve

V
is

posi

tioned

at
R

range
the
oil

having
the

line

pressure
7
is

directed
to
the
line

pressure
circuits

5
and
6
The

pressure
in

the
circuit

ID
actuates

the

low

and
reverse
brake
after

being

introduced
into

the
line

pressure
cir

cuit

I2

through
the
lst

2nd
shift

valve

ID
The

pressure
in

the

circuit

operates
the
release
side
ofband

servo

and
the
front
clutch
after

being
led

to

the
line

pressure
circuit

10

through

the
2nd

3rd
shift
valve

@
The

throttle

pressure
16
and
the

line

pressure
6
which

vary
with
the

degree
of
the

depression
of
accelerator

pedal
both
act
on

the

pressure
regula

tor
valve

CD
and

press
its
valve

CD

increasing
the
line

pressure
7
In
R

range
the

governor

pressure
is
absent

making
all
sllch
valves

inoperative
as

the
lst
2nd

shift

valve

@

2nd
3rd
shift
valve
and

pressure

modifier
valve

@
CHASSIS

R

C

Fig
AT
26
Power
transmission

during
R

range

lI

a

Go

I
w
L

AT085

Fig
AT

27

Operation
of
each
mechani6m

duirng
OR

range

Clutch
low
Band
servo
One

Parking

Ran
Gear

ratio
reverse

way

pawl

Front
Rear

brake
Operation
Release

clutch

Park
on
on

Reverse
2
182
on
on
on

Neutral

01
low
2
458
nn
on

Drive
D2
Second
458
nn
on

OJ

Top
1
000
on
on

2
Second
458
nn

t2
Second
458
on

tt
low
2
458
on
on

AT

16

AUTOMATIC

TRANSMISSION

R

range
Reverse

o
fro

Clutch
R

Clutch
Low
0

R

8

B
e

Torque
Con

14

Q

T
CO
fI

I
9
ID
v

Th

Vel

r

j
Orei

1
Ve

Front

Lubdce

O
IfQ

Cheek

Vah
OJ

iJ

Thronle

D
ein

V
D
i
V

l

x

21

CDp

R
Iulato
Velv

@

Not

M
k
r
D
ein

Unep
n
IGover
o

t
t
praaur
1

G
l
Gov
r
o

pr

Torque
CO

rler

p

ThrOU

epr
s
cOnclMV

Gov
nOt
V
P

i
V

Gov
nor
Velv

Fie
A
T
28
Oil

pressure
circuit

diagram
R

range
RelJerse

AT
17

CHASSIS

rang
e

eutral

In
N

range
all

the
clutches
and

band
are

not

applied
therefore
no

power
is
triJllsmilted

10
the

output

shaft

The

pressure
of
oil

discharged
from

the
oil

pump
is

regulated

by
the

pressure
regulator
valve

D
to
maintain

the
line

pressure
7
and
the
oil

is
led

to
the

manual
valve

r
2
vacuum
throt

tle
valve

@
and
solenoid
downshift

valve

@
The
oil
is

further
introduced

into
the

torque
converter
at
its

operat

ing
pressure
14
and

a

portion
of
this

oil

is
distributed

to
each

part
as
the

front
lubricant
The
oil

which
has
been

discharged
from
the

torque
converter

is
also

distributed
to
each

part
as
the

rear
lubricant

As
the

oil

pump
rotates
at
the

same

speed
as
thal
of
the

engine
the

dis

charge
of
oil

pump
increases
with
the

engine
speed
But

the

surplus
oil

is

returned
to
the

oil

pan
by
the

pressure

regulator
valve

D

I

l
nUI

h
lo
BJnd
oefVQ
On

Parkin
Gt
ar

Rang
e
rl
tro
e
lA

a

pawl
ratio

Front
RUT
brake
Operation
Rdu
e

clutch

Park
on
on

Revtr
21Rl
on
on
on

Neutral

01
Low
2
458
on
on

Orive
02
Second
1
458
on
on

OJ

Top
1000
on
on

ton
on

2
cond
1
58
on
on

12
Second
1
458
on
on

I

II
low
2
458
on
on

AT
iS

AUTOMATIC
TRANSMISSION

UN

range
Neutral

Low

R

Brek

B
eke

B

x

12

VK

Th
o
I

V
lv
7

G
0

j

Lve

Fro

Lub
lc
l

Otifite

Check

Valve
D

alnValve
j

11

I
3

ThrOUle

OrOlln

Vah
f
11

J

l

8
5018

Back
up
g

Dow
ill
V
lv

V
v

P
Modif

V
lve

15

13

8Jlux

3

j
p
ssu

A
euleto
Velye
6

lL

2
Menuel

V
lv

iiJIN
NOI
M
ked
O
in

Lin
pre
lGovernor
teed

pr
e

Gove
no

pr
s

Torquecon
e

p
e5SU

ThroW

p
S
Ond

y

G
o
V

8
Primary

Goy
no
V
l

Fig
A
T
29
Oil

pressure
circuit

diagram
N

range
Neutral

AT
19

CHASSIS

D

range
Low

gear

The

low

gear
in
D

range
is

somewhat
different
from
that
in

II

range

The
rear
clutch

is

applied
as
in

range
but
the
une

way
duldl
is

holding
the

connecling
drum
The

power
flow
is
the
same

as
in

11

range
That
is
the

power
flow
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
the

rear
clutch

dri
es

the
rear
clutch

hub
and

from

internal

gear

The
front
inlernal

gear
rotates
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

Tear

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

flange

clockwise

The
internal
drive

flange
is

splined
to
the

output
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
I
2

and
3

The

pressure
in
the
circuit
I

actuates
the

rear
clutch
and
the

gover

nor
and
at
the
same

time

operates
the

lst

2no
shift
valve

ID
to

change
the

speed
The
circuit
2
leads
to
the

second
lock
valve

@
The
circuit
3

actuales
the
2nd
3rd

shift
valve

0

for
the
2nd

3rd

speed
change
and

at
the

same
time

locks
the
second

lock
valve

@

The
throllIe

pressure
16

which

changes
with
the

degree
of
accelerator

pedal
depression
presses
the

pressure

regulator
valve

CD
and
increases
the

line

pressure
7
When

Ihe

speed
of

vehicle
has
increased
the

governor

pressure
J
5

inlroduced
from
the
line

pressure
circuit

ll
actuates

the

lst
2nd
shift

valve
ID
2nd
3rd

shift
valve

@
and

pressure
modifier

valve

@
When
the

governor
pressure

is

high
the

pressure
modifier
valve

CID

acts
in
such

a
direction
as
to

compress
C

AT080

Fig
A
T
30
Power
transmission

during
V
range

ATOP1
dmifi

Fig
AT

3
Operation

of
each
mechanism

during
VI

range

G
Clutch
Low

Band
rVo
One

Parking

Ro
reverse

woy

pawl
ratio

Front
Rear

brake
Operation
Release

clutch

Park
on

on

Reverse
2
182
on
on

on

Neutral

01
low
14

8
on
on

Drive
01
Second

1
458
on

on

03

Top
1
000
on
on
on
on

1
Second
1
458
on
on

tl
Second
1
458
on
on

1

II
low
2
458
on
on

rhe

spring
and
the

throttle

pressure
is

led

10
the
throllIe

pressure
18

This

pressure
acts

againsr
the
force
of

spring
of
the

pressure

regulator
valve

CD
and
also

against
the

Ihrollle

pres

sure

16
thus

lowering
the
line

pres

sure
7

The

governor
pressure
also

increases

with

the

speed
of
vehicle

exerting
a

pressure
on
one
side
of

the
1st

2nd

shift

valve
and

counteracts
the

throt
lie

p
ssure
19
line

pressure
I
and

the

spring
which
are

exerting
against

the

governor

pressure
Therefore

when

the

governor
pressure
exceeds

this

pressure
the

speed
is

shifted
from

Ihe
I
Sl

gear
10
the

2nd

gear
The

further
the

acceleraror

pedal
is
de

pressed
the

higher
becomes
the

throt

tle

pressure
19

increasing
the

gover

nor

pressure
and

shifting
the

speed

change

point
to
the

higher
side

AT
20