torque DATSUN PICK-UP 1977 Workshop Manual

space
from
the
throttle

pressure
16

to

the
drain

17
decreases

and
the

space
from
the
line

pressure
7
to

Ihe

throttle

pressure
16
increases

Consequently
the
throttle

pressure

16
increases

and
the

valve
is

bal

anced

Contrarily
when
the

engine

torque
lowers
and
the

negative
pr

sure
in

the
intake
line

lowers

tending

toward
vacuum
the
force
of
the

rod

depressing
the
valve
decreases

and
the

throttle

pressure
16
also
decreases

When

pressure
regulated

by
the
throt

tle

back
p
valve
described
in
the

subsequent
paragraph
is
led
to
circuit

17
a

high
pressure
is

applied
through

the

space
from

the
circuit
17
to
the

throttle

pressure

16
Consequently

the
VTV
is
unbalanced
the

throttle

pressure
16
becomes

equal
to
the

back

up
pressure
17
and
the

valve
is

locked

upward

I

16

III
AT100

Fig
AT
15

Vacuum

throttle
valIN

Throttle

back

up
valve

TBY

Usually
this

valve
is

depressed

downward

by
the

spring
force

and

circuit

17
is

drained

upward

As

soon
as
the
lever
is

shifted
either

to
2

or
I

range
line

pressure
is

led
from

circuit
4

the
line

pressure
is

applied
to
the
area
difference

of
the

valve
the

valve
is
forced

upward
the

space
from

circuit
4
to
circuit

17
is

closed

and
with
the

space
from
circuit
Automatic
Transmission

17
to
Ihe

upper
drain
about
to

open

the
back

up
pressure
17
which
is

lower
than
the

line

pressure
4

by
the

pressure
loss
due
to
the

space
from

circuit
4
to

circuit

17
is
balanced

with

the

spring
force

Further
when

gear
is

shifted
from

2nd

to
Low

at
the

range
I
line

pressure
is

led
from
circuit

12
and

the
line

pressure
is

applied

pward
to

the
bottom
of
the

valve

through
the

valve
hole

Consequently
the
valve
is

forced

upward
and
locked
As
a

result
the

space
from
the
line

pressure

4
to

the
back

up
pressure
17
is

closed

completely
and
the
back

up

pressure
17
is

drained

upward

AT101

Fig
AT

16
Throttle
back

up
lJ
Jlve

Solenoid

downshift
valve

SDY

This
valve

is
a
transfer
valve
which

leads
the
line

pressure
7

to
13

and

transmits
the
same
to
the
FSV
and

SSV
when
a
kickdown

signal
is
re

ceived
from

the
downshift
solenoid

Usually
the
solenoid

push
rod
and

valve
are
locked

upward
by
the

spring

in
the
lower
end
and
the
circuit
from

line

pressure
4
to
line

pressure
13
is

opened

When
kickdown
is

performed
the

push
rod

operates
Ihe
valve
is
de

pressed
downward
and
the

circuit

from
line

pressure
7
to

line

pressure

13

opens
Line

pressure
13

opposes

the

governor
pressure
15
at

Ihe
SSV

and
FSV
thus

accomplishing
the

downshift

operation

AT
10
r

AT102

Fig
AT
17

Solenoid

dow
hift
valve

Second

lock

valve
SLY

This
valve
is
a
transfer

valve
which

assists
the
shift

valve
in

determining

the
fixed

2nd

speed
at

the
2

range

In

the
D

range
the

sum
of
the

spring
force

and
line

pressure
3

APplied

upward
xce
ds
the

linepres

sure
2
which
is

applied
to

the
valve

area
difference

as
a
downward
force

As
a
result

the
valve
is

locked

upward

and
the
circuit
from
line

pressure
8

to
line

pressure
9
is

opened

Consequently
the
FSV

becomes

the
2nd

speed
condition
and
line

pressure
is

led
to

the
band

servo

engaging
circuit
9

only
when
line

pressure

1
is
released

to
line

pressure

8

In
the
2

range
the

upward
force

is

retained

only
on
the

spring
and
the

downward
line

pressure
2

exceeds

the

upward
force

As
a
result
Ihe
valve
is

locked

downward
line

pressure
2
is

released

to

9

regardless
of
the

operating

condition
of
the
FSV
and
the

band

servo

is

engaged

J

2

8

ATl03

3

Fig
AT
18
Second
lock
lJ
Jlve

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

fhe
numeraJs
show

the
circuit

num

bers

Pressure
source
of
the
line
7

Operating
Iinc

prcssure

for
friction
elements

123456
8910
1112

Auxiliary
line

pressurc
13

Throttle

system
pressure

16
17
18

19

Others
14
15

Oil

pump
discharge
hole
7

Cd

Torque
converter

pressure
14

Rear
iutch

prc
surc
1

FTOOI
c1
tL
h

prc
ur

It

J
1
011
pump
Sllctlon
hole

M

IIJ1iIII
Automatic
Transmission

Fig
AT
21

Identification
of
oil
channels

in
oil

pump
AT105
Oil

pump
suction
hole

ATl06

Fig
AT

22

Identification
of
oil
channels
in
case

front
face

I
o

Oil

pump
dischar
hole
7

I9JM

c

Torque
converter

f
Os
I
1L

0
ervo
Ie
ease

pressure
14

0
pressure
10

Rear
clutch

Servo
t

ightening

ho
L

pressure
l
0
1

pressure
9
lJ
L

I
c

I

Front
clutch
IT

0

LIO
reverse
brake

pressure
12

U

r
FT

II
pressure
11

rrOil
pump
suction
hol

J

C
Jf
JC
O
Governor

pressure
15

Governor

feed

pressure
l

An07

Fig
AT
23

Identification
of
oil
channels

in
case

face

AT
13

R
RANGE
REVERSE

In
R

range
the

front
clutch
and

the
low
and
reverse
brake
are

applied

The

power
flow
is

through
the

input

shaft
front
clutch
and

connecting

shell
to
the

sun

gear
Clockwise
rota

tion
of
the
sun

gear
causes
counter

clockwise
rotation
of
the

rear

planeta

ry
gears
With
the

connecting
drum

held

stationary
by
the
low
and

reverse

brake
the
rear

planetary
gears
rotate

the
rear
internal

gear
and
drive
the

flange
counterclockwise
The

rear

drive

flange
splined
to
the

output
shaft

rotates
the

output
shaft
counterclock

wise
at
a

reduced

speed
with
an

increase
in

torque
for
reverse

gear
Automatic
Transmission

R

Fig
AT

26
Power

tranamis
ion

during
R

range

m
i

1

A
TOBS

Fig
A
T
21

Optrationof
each
mechanism

during
R

range

When
the
manual
valve

V
is

posi

Clutch
Low

Band
servo
One

tioned
at

R

range
the
oil

having
the
Gear

Partina

Ranae
re
ne

way

line

pressure
7
is

directed
to
line
ralio

Front
Rear

brake
Openlion
Relulie

clutch
plwl

pressure
circuits
5

and
6
The

pressure
in
the
circuit
5
actuates
the
Park
on
on

low
and
reverse

brake
after

being
Ruene
2
182
on
on
on

introduced

into
line

pressure
circuit

Neutral

12

through
the
I

st
2nd
shift
valve

ID
The

pressure
in

the
circuit

op
DI
Low
2
458
on
on

erates
the
release
side
of
the
band

servo
and
the
front
c1u
tch
after

being
Driowe
D2
Second
1
458
on
on

led
to
line

pressure
circuit
0
D3

Top
1
000
on
on
on

through
the
2nd
3rd
shift
valve

@

2
Second
1
458

The
throttle

pressure
I
6
and
the
line
on
on

pressure
6
which

vary
with
the

12
Second
S8
on
on

degree
of
accelerator

pedal
depression

II
Low
2
458

both
act
the

pressure
regulator
on

on

on

valve

CD
and

press

against
its
valve

CD

increasing
line

pressure
7
In
Rn

range
the

governor

pressure
is
absent

making
all

such
valves
as
the
1st
2nd

shift
valve

ID
lnd
3rd
shift

valvc

@
and

pressurc
modifier
valve

inoperative

AT16

R
range
Reverse

Torq
Con

Oil
Cool
r

A
r

Lubt

lcetlon

0

II
iL
Vel

o

Front

or
ln

l

n

jL
r

x

Q

A
uletor

Val

NIJte
kld
Automatic
Transmission

@
2nd
3n
l

Timl
lil

1i
II

r

U

nu

r
l3
ni

II

15
15
Front

Cll
ltc
Il
Low

a
Aev

Br
k

B
k

II
I

LJ

2f
ID
p
Mc
e
lf
v

If
I
I

CID
VEL
1

Thrc

r

V
I

I

11
1

IU

T
R

Clutch

f

r

Ir
l
II

Orlflc

Check

Velve

22

n
@lnd
3rdShlft

v

D
h
III

r
r
I

I

111

L

Ll
p
O
nOl
f
t

p
r

Goy
norpreat
l

Torque
Ilrfl

r

Throttl

D
ln

v

5

1

O
eln

rmrp

Throttl
p
a
nor
v
11

J

I

t

Q
V

1ve

Fig
A
T
28
Oil

preBBure
circuit

diagram
R

range
Reverie

AT
17

N
RANGE

NEUTRAL

In

N

range
none
of

the
clutches

and
band
are

applied
thus
no

power
is

transmitted
to

the

output
shaft

The

pressure
of
oil

discharged
from

the
oil

pump
is

regulated
by
the

pressure
regulator
valve

Dto
maintain

the
line

pressure
7

and
the
oil
is

led

to
the
manual
valve

@
vacuum
throt

tie
valve

@
and
solenoid
down
shift

valve

@
The
oil
is
further
introduced

into

the

torque
converter
at
its

op

erating

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
con

verter
is

also
distributed
to
eacn

part

as
the

rear
lubricant

As
the
oil

pump
rotates
at
the
same

speed
as
the

engine
the
oil

pump

discharge
increases
with

engine

speed

But
the

surplus
oil
is
returned
to
the

oil

pan
by
the

pressure
regula
tor
valve

D
Automatic
Transmission

Geu
Clutch
Low
4

Band
crvo
One

Pultin

R

atio
WI

pawl

Front
Rear

brake
Operation
Release

clutch

Park
on
on

Reverse
2
182
on
on
on

Neutral

Dt
Low
2
458
on

on

Drive
D2
Second
1
458
on
on

m

Top
1
000
on
on

on
on

2
Second
1
458
on

on

12
Sec
ond
1
458
on
on

II
Low
2
458
on
on

AT
la

Automatic
Transmission

R
RANGE
REVERSE

R

In
R

range
the

front
dutch
and

the
low
and

reverse
brake
are

applied

The

power
flow
is

through
the

input

shaft
front
clutch
and

connecting

shell
to

the
sun

gear
Clockwise
rota

tion

of
the

sun

gear
causes
counter

clockwise
rotation
of
the
rear

planeta

ry

gears
With
the

connecting
drum

held

Slationary
by
the
low
and
reverse

brake
the
rear

planetary
gears
rotate

the
rear
internal

gear
and
drive
the

flange
counterclockwise
The
rear

drive

flange
splined
to
the

output
shaft

rotates
the

output
shaft
counterclock

wise
at

a
reduced

speed
with
an

increase
in

torque
for
reverse

gear

f

When
Ihe
manual
valve

CV
is

posi

tioned
at
R

range
Ihe
oil

having
Ihe

line

pressure
7
is

directed
to

line

pressure
circuits
5
and

6
The

pressure
in

the
circuit
5
actuates
the

low
and
reverse
brake
after

being

introduced
into
line

pressure
circuit

12

through
the
I
st

2nd
shift
valve

@
The

pressure
in
Ihe

circuit

op

erates
the
release
side
of
the
band

servo
and

the
front
clutch
after

being

led
to

line

pressure
circuit

10

through
the
2nd
3rd
shift
valve

@

The
throtlle

pressure
16
and
the
line

pressure
6

which

vary
with
the

degree
of
acceJerator

pedal
depression

both
act

on
the

prcssure
regulator

valve

CD
and

press

against
its
valve

CD

increasing
line

pressure
7
In
R

range
the

governor

pressure
is
absent

making
all
slldl

valves
as
the
J
SI

2nd

shift
valve

@
2nd
3rd
shift
valvc

@
and

pressure
modifier
valve

j

inoperative
C

Fig
AT

26
Power

transmi
ion

during
R

range

A
TOS5

Fig
AT
27

Operation
attach
mechanism

during
R

range

G
Clutch
Low
A

Band
servo
One

Parkin

Ran
no
wa

plwl
ratio

Front
Rear

brake

Operllioo
Rdr
ue

clutch

k
on
on

Revctte
1
181
on
on
on

Neutnl

DI
Low
1
418
on
on

Driw
D2
Second
1
458
on
on

DJ

Top
1
000
on
on
on
on

2
Second
1
458
on
on

12
Second
1
458
on
on

I

II
Low
2
458
on
on

AT
16

N
RANGE
NEUTRAL
Automatic
Transmission

In
N

range
none
of
the
clutches

and
band
are

applied
thus

no

power
is

transmitted
to
the

output
shaft

The

pressure
of

oil

discharged
from

the
oil

pump
is

regulated
by
the

pressure
regulator
valve

CD
to
maintain

the
line

pressure
7
and
the
oil
is
led

to
the
manual
valve

V
vacuum
throt

tle
valve

@
and
solenoid
down
shift

valve

@
The
oil
is

further
introduced

into
the

torque
converter
at
its

op

erating
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
con

verter
is
also
distributed

to
eacn

part

as
the
rear
lubricant

As

the
oil

pump
rotates
at
the
same

speed
as
the

engine
the
oil

pump

discharge
increases
with

engine
speed

But
the

surplus
oil

is
returned
to
the

oil

pan
by
the

pressure
regulator
valve

CD
G
Clutch
Low

Band
servo
One

Pukiq

R
w

pawl
ntlo

Front
Rur

br
ke
Optruion
Release

clutch

PIlIi
on
on

Reverse
2
182
on
on
on

Neut
1

01
Low
2
458
on
on

Drive
02
Second
t
458
on
on

03

Top
1
000
on
on
on
on

2
Setond
1
458
on
on

12
Second
1
4
58
on
on

1

II
Low
2
458
on
on

AT

18

Automatic

Transmission

0

range
Low

gear

Torque
Conven
Front

Clul
L
A

e

B

6
Clutch

I

Q

011

Cool
TIC
011

p

V

RUf

LubtJuflon

n

Ii
IO
lln

V
l

F

ont

Lub
lclt
n

D
nV

l

ThroW

0
1

V

I

Q
P
P

tOO
V

Note
U
X
Ir

or
n

Llnep
IO
nor
feed

GoY
no
p

Torque
co

p

Th
on
I

ID
v

Th
O

V

Orifice

V

L

13

t

12

tt
2NtSt
llttY

5

i

Iecotodary
Y

QoY
nOl
V
Oew
roo
v

Fig
A
T
32
Oil

pressure
circuit

diagram
uD

1
range
Low

gear

AT
21

D
RANGE
2ND
GEAR
Automatic
Transmission

t
In
this
case
the

rear

c1ut
h

IS

applied
and
the
band
brake

holds
the

fronl

dUh
h
drum
the

connecting

shell
and
the
sun

gear
from

rotating

The

power
flow
lakes

place
through

the

input
shaft
into
the

rear
clutch

and

the
front
internal

gear
With
the
sun

gear
held

stationary
the
front

planeta

ry
gears
rotate

around
the

sun

gear

carrying
the
front

planet
carrier

with

them
The
fronl

planet
carrier

being

splined
to
the

output
shaft
causes

clockwise
rotation
of
the

output
shaft

at
a

reduced

speed
compared
with
the

speed
of
the

input
shaft
with

an

increase
in

torque
As
the
low
and

reverse
brake

is
not

applied
the
clock

wise

rotation
of
the

output
shaft

causes
clockwise
rotation

of
rear
inter

nal

gear
and
the
rear

planet
carrier

also

rotates
around

the
sun

gear
in

a

clockwise
direction

The
one

way

clutch

will
act

to
allow
the
clockwise

rotation
of

connecting
drum

When
the
car

speed
increases

while

running
at
D

range
I
st

gear
the

st
2nd
shift

valve

ID
moves
allow

ing
the
line

pressure
I
to
be
intro

duced
into
the
line

pressure
8

Ihrough
itself
The
line

pressure
8
is

further
led
to

the
line

pressure
9

through
the
second
lock
valve

@
and

by
locking
the
band
servo

obtains
the

2nd

gear
condition
Fig
AT
33

Power
transmission

during
Dz

range

A

T079

Fig
AT
34

Operation
of
each
mechanism

during
D

range

Clutch
Low

Band
servo
On

Patking

G

Range
reverse
w

pawl

ratio

Fronl
Rur
brake
Optrltion
Release

clutch

PlIk
on
on

Revtne
2
182
on
on
on

Neutral

01
Low
2
4S8
on
on

Drive
02
Second
1
4S8
on
on

OJ

Top
1
000
on
on
on
on

2
Second
1
4S8
on
on

12
Second
1
4S8
on
on

1

II
Low
2
4S8
on
on

AT
22

Automatic
Transmission

I

M
nual

f4fL
J

0
I
1
r

PR
0

range
kickdown
Shift
valves
In
2nd
gear
position

To

queeO
t
Front

Clutch
Low
a

A

8

8
e
e

a

o

14

0

Oil

COO

R
L
ubrication

n

0

Drain
1
4

j

v

I

Front

Lub
icet

p
n
o

I

Thron

p
ain

V

I

j

R
gu
ato
V

I

Not
Ma
ked
X
r
p
n

Li
pr
IGo
no
f
d

p
l

Governor
p

c
Torque
CO
I
1

p

ThrOWepr
VK

Th
o

V
lv
7
1

iftV
8
Throttle

BKk
up

V
hl
ID
So
e

COw

P
Ifk

Check

V

I

1
24
5
Mod
Yo

I

@2nCl
3rdSl
lilr

V

12

3
ht
2nd
Shih
V

5

L

I
X

S
COnd

Primary

G
rw
Va
Gov
nor
Valve

AT
27
Fig
AT
39
Oil

pressure
circuit

diagram
D

ronge
kickdown
shift
values
in
2nd

gear
position