engine oil DATSUN PICK-UP 1977 Service Manual

REMOVAL

In

dismounting
transmission
from

the
vehicle

proceed
as
follows

I
Disconnect
battery
ground
cable

from
terminal

2

Place
transmission
control
lever
in

neutIal

position

3
Remove
E

ring
and
control
lever

pin
from
transmission

striking
rod

guide
and
remove
control
lever
See

Figure
MT
4

TM335

Fig
MT

4
Remouing
controllelJ
r

4
Jack

up
the
vehicle
and

support

its

weight
on

safety
stands
Use
a

hydraulic
hoist
or

open
pit
if
avail

able

Confirm
that

safety
is
insured

5
Disconnect
exhaust
front
tube

6
Disconnect
wires
from
reverse

lamp
switch
See
Figure
MT
5

7
Disconnect

speedometer
cable

from
rear
extension

housing
See

Figure
MT
5

8
Remove
clutch

operating
cylinder

from
transmission
case
See

Figure

MT5

O

m

J

@

1

Speedometer
cable

2
Reverse

lamp
switch

3
Outch

operating
cylinder

TM774

Fig
MT
5
Bottom
view
of
car
Manual
Transmission

9
Remove
bracket

holding
center

bearing
on
3rd
crossmember

by

loosening
off

attaching
bolts
See

Figure
MT
6

PD219

Fig
MT

6
Removing
center
balring

holding
brucket

10
Uetach

propeller
shaft
from

companion
flange
of

gear
carrier

by

removing
four
bolts

See

Figure
MT
7

Not

a
Remove

propeller
shaft

carefully
so

as
not
to

damage

spline
sleeve

yoke

and
rear
oil
seal

b

Plug

up
the

opening
in
the

rear
of

rear
exteDSion

housing
to

prevent

oil
from

flowing
out

P0220

Fig
MT
7

Remouing
four
bolt

6ecuring
prop
ller

shtJft
to

companion
ltJnge

11

Support
engine
by
locating
a

jacft
under
oil

pan
with
a
wooden

block
used
between
oil

pan
and

jack

12

Support
transmission
with
a

transmissionjack

13
Remove
exhaust

pipe
btacket

by
unscrewing
attaching
bolts
2

California
models

only
See

Figure

MT
8

14
Remove
rear

engine
mounting

insulator

securing
bolts
I
and
rear

mounting
member

securing
bolts
3

See

Figure
MT
8

MT
4
E
A277

Fig
MT
8

Removing
engine
mounting

rear

support

15

Remove
starter
motor

16
Remove
bolt

securing
transmis

sion

to

engine

After

removing
these
bolts

support

the

engine
and
transmission
with

jacks

and
then
slide
tra
ion
rearward

away
from

engine
and
remove
from

the
vehicle

Note
Take
care
in

dismounting
trona

mission
not
to
strike

any
adjacent

parts
and
main
drive
shaft

DISASSEMBLY

TRANSMISSION
CASE

DISASSEMBLY

I
Prior
to

disassembling
transmis

sion

thoroughly
wipe
off
dirt
and

grease
from
it

2

Drain
oil

thoroughly

3
Remove
dust
cover
from
trans

mission
case

Remove
release

bearing
and
with

drawallever

4

Remove
reverse

lamp
switch

5
Move

gear
to
Neutral

6
Remove
speedometer
pinion
and

pinion
sleeve

by

taking
off
lock

plate

7
Remove
E

ring
and

stopper
guide

pin
from
rear
end
of

re
ll
extension

See

Figure
MT

9

TM337

Fig
MT
9

Removing
triking
rod

E

ring
and

topper
pin

REAR

EXTENSION

DISASSEMBLY

Remove
lock

pin
from

striking

lever
and
remove

striking
rod
Manual
Transmission

Note
00

not
diSlssemble

rear
exten

sion
bush
from

rear
extension

ADAPTER
PLATE

DISASSEMBLY

I

Remove
six

6

bearing
retainer

attaching
screws
with
an

impact

wrench
and
remove

bearing
retainer

from

adapter
plate

2

Remove
reverse
idler
shaft

3
Remove
mainshaft

bearing
from

the
rear
extension
side

INSPECTION

Wash
all

parts
in
a
suitable

cleaning

solvent
and
check
for
wear

damage
or

other

faulty
conditions

Notes

a
Be
careful

not
to

damage
any

parts

with

scraper

b

00
not

clean
wash
or
soak
oil
seals

in
solvent

TRANSMISSION
CASE

AND

REAR

EXTENSION
HOUSING

I
Clean
with

solvent

thoroughly

and
check
for

cracks
which

might

cause
oil
leak

or
other

faulty
con

ditions

2

Check

mating
surface
of
the

case

to

engine
or

adapter
plate
for
small

nicks

projection
or
sealant
e
1
Control
lever

2

Striking
rod

guide

3

Striking
rod

4

Striking
lever

5

Return

spring
plug

6

Stopper

pin

TM353

Fig
MT

27

Exploded
view
of
shifting
mechani6m

Remove
all

nicks

projection
or

sealant
with

a
frne

stone

3

If
rear

extension
bush
is

worn
or

cracked

replace
it
as
an

assembly
of

bush
and
rear
extension

housing

BEARING

I

Thoroughly
clean

bearing
and

dry

with
a

compressed
air

2
When
race
and
ball
surfaces
are

worn
or

rough
or
when
balls
are
out

of

round
or

rough

replacebearihg

with
a
new
one
See

Figure
MT
28

I

TM372

Fig
MT
28

l
pecting
ball

bearing

3

Replace
needle

bearing
if

worn
or

damaged

GEARS
AND

SHAFTS

I

Check
all

gears
for
excessive

wear

chips
or
cracks

replace
as

required

MT
8
2

Check
shaft
for

bending
crack

wear
and
worn

spline
if

necessary

replace

3
Measure
backiasii
in

gears

Standard

0
05
to0
10mm

0
0020
to
0
0039
in

If
the
above
limits
are
exceeded

replace
drive
and
driven

gears
as
a

set

4
Measure

gear
end

play

1st

gear

0
32
to
0
39
mm

0
0126
to
0
0154
in

2nd

gear

0
12
to

0
19
mm

0
0047

to
0
0075
in

3rd

gear

0
13
to
0
37
mm

0
0051
to
0

0146
in

TM374

Fig
MT

29

Measuring
end

play

5

Apply
a

light
coat

of
multi

purpose
grease
to

withdrawal
lever

release

bearing
and

bearing
sleeve
in

stall
them
on
clutch

housing

After

connecting
them

with
holder

spring
instaU
dust

cover
on
clutch

housing

6
Install
control
lever

temporarily

and

shift
control

lever

through
all

gears
to
make

sure

that

gears

opera
Ie

smoothly

Note
Install

drain

plug
and
filler

plug

ith
sealant
in

place
Manual

Transmission

INSTALLATION

Install
the
transmission
in
the
reo

verse
order
uf
removal

paying
atten

tion

to
the

following

points

1
Before

installing
dean

mating

surfaces
of

engine
rear

plate
and

trans

mission
case

2

Before

installing
lightly
apply

grease
to

spline
parts
of
clutch
disc

and
main
drive

gear

3

Tighten
bolts

securing
trans

mission

to

engine
to

specifications
See

Figure
MT
55

5
SPEED
TRANSMISSION

TYPE

DESCRIPTION

REMOVAL

DISASSEMBL
Y

TRANSMISSION
CASE
DISASSEMBLY

DISASSEMBL
Y
OF
GEAR

ASSEMBLY

REAR

EXTENSION
DISASSEMBLY

ADAPTER
PLATE

DISASSEMBLY

INSPECTION

TRANSMISSION
CASE
AND
REAR

EXTENSION
HOUSING

DESCRIPTION

The
transmission

is
of
a
5

speed

forward
with
overdrive
4

OD

speed

fully
synchronized
constant

mesh

type
that

uses
helical

gears

The
5

speed
transmission
covered
in

this
section
is

similar
in

all

respects
to

the
4

speed
transmission

type

F4W71B
stated

previously
except
the
CONTENTS

MT14

MT17

MT17

MT17

MT17

MT18

MT19

MT19
4
4

to
5
9

kg
m

32
to
43
ft
Ib

1

0
9
to
1
2

kg
m

7
to
9
rt
lb
TM773

Fig
MT
55

Tightening
torque

4
Remove
filler

plug
and
fIll
trans

mission
with
recommended

gear
oil

to

the
level
of
the

plug
hole

Approxi

mately
I
7

liters
3

pt
3

pt

FS5W71B

BEARING

GEARS

AND
SHAFTS

BAULK

RING

OIL

SEAL

ASSEMBL
Y

FRONT
COVER
ASSEMBLY

REAR

EXTENSION

ASSEMBLY

GEAR

ASSEMBLY

TRANSMISSION
ASSEMBLY

INSTALLATION
MT19

overdrive

position
of
it

The

overdrive

gear
rides
on
the

mainshaft

freely
through
the

needle

roller

bearing
and
counter

overdrive

gear
is
fitted
to
the

countershaft

by

splines

The
overdrive

synchronizer
system

is

on
the
mainshaft
rear
side

MT14
MT19

MT19

MT19

MT19

MT19

MT19

MT19

MT19

MT

20

MT20

Placing
the
control
lever
in

over

drive

position
brings
the
reverse
OD

coupling
sleeve
reverse

gear
on
main

shaft
into
mesh
with
overdrive
clutch

gear
The
reverse
OD

synchronizer

hub
is

fItted

to
the
mainshaft

by

splines
so
the
overdrive

gear
on
main

shaft

turns

together
with
the
main

shaft

Manual

iTransmission

TIGHTENING
TORQUE

Installa
tion

Engine
to
transmission

installation
bolt

Transmission
to

engine
rear

plate
bolt

Clutch

operating
cylinder
installation

bolt

Rear

mounting
insulator
to

transmission
installation
bolt

Crossmember

mounting
bolt

Propeller
shaft
to
diff
installation
bolt

Gear

assembly

Rear

extension
installation
bolt

Front
cover

installation
bolt

Bearing
retainer
to

adapter

plate
screw

Main
haft
nut

Check
ball

plug

Stri
lever

lock

pin

Reverse
select

return

plug

Speedometer
sleeve

locking

plate
nut

Reverse

lamp
switch

year
oil
Ier

pl
g

Ge
r
oil
drain

plug
Unit

kg
m
ft
lb

4
4

to
5

9
32

to
43

0

9

to
1
2
7
to
9

2
5

to
3
0

18
to
22

0
8
to
1
1
6

to
8

3

2
to
43

23
to
31

2
4

to
33

17
to

24

1

6

to
2
1

12
to
IS

1
6
to
2
1

12to
IS

1
9
to
2
S
14
to
18

14

0
to
17
0

101
to
123

1
9
to
2
S

14
to
18

0
9
to
1
2

7
to
9

0
9
1
2
7

to
9

0
4

to
O
S

3

to
4

2
0
to
3
0

14
to
22

2
S

to
3
5

18
t02S

2
S

toTS

l8
to
2S

or

SPECIFICATIONS

Gear
backlash

Maindrive

gear
to
counter
drive

gear

1st

gear

2nd

gear

3rd

gear

OD

gear

Gear

end

play

1st

gear

2nd

gear

3rd

gear

OD

gear

Counter

gear

Reverse
idler

gear

Clearance

between
baulk

ring
and

gear

All

gears

Counter

bearing

adjusting
shim
Unit

mm
in

0
05
to
0

10
0
0020
to

0
0039

0
05
to
0

20
0
0020
to
0
0079

O
OS
to
0
20
0

0020
to
0
0079

0
05
to
0
20
0
0020
to
0
0079

0
05
to
0

20
0
0020
to
0
0079

0
32
to
0
39

0
0126
to
0
0154

0
12
to
0
19

0
0047
to
0

0075

0
13
to
0
37
0
0051
to
0
0146

0
32
to
0
39

0
0126
to
0

0154

0
01
to
0
21

0
0004
to
0
0083

0
05

to
0
20
0
0020

to
0
0079

1
25
to
1

60
0
0492
to
0
0630

0
6
0
024

0
5
0
020

0
4
0

016

0
3
0
012

0
2
0
008

0
1

0
004

MT
22

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

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

plate
The

parking
rod

pin
operates
the

rod
at
p

range
and

operates
the

mechanical

lock

system

The

above
described
manual
shaft
is

further

equipped
with

an
inhibitor

switch
A

rotor

inside
the

inhibitor

switch

rotates
in

response
to
each

range
When
tne

range
is

selected
at

p
or

N
the
rotor

closes
the

starter

magnet
circuit

so
that
the

engine
can
be
started
When
the

range

is

selected
at
R
the
rolor
closes
the

back

up

lamp
circuit
and
the
back

up

lamp

lights

CD

1
Manual

pia
te

2
Inhibitor

switch
ATOB7

Parking
rod

Manual
shaft

Fig
AT
4

Manual

linkage

VACUUM

DIAPHRAGM

The

vacuum

diaphragm
is

installed

on
the
left

center

portio
n
of
the

transmission

case
The

internal
con

struction
of
the

vacuum

diaphragm
is

as
follows

A
rubber

diaphragm
forms
a

parti

tion
in
the

center
The

engine
intake

manifold

negative
pressure

l
led

through
a

vacuum
tube
and

spring

force
is

applied
to
the
front
surfaceof

the
rubber

diaphragm
while

atmos

pheric

pressure
is

applied
to
the
back

surface
The
difference

between

pres

sure

applied
to
the
front
and
ba
K

I

surfaces
causes
a

vacuum
reactIOn

which
activates
the
throttle
valve
of

the
control
valve
inside
the
transrhis

sion

case

Wheri
accelerator

pedal
is

fully
de

pressed
and
the
buretor
is

fU

IIy

opened
but
th

engirie

sp
eed
is

not

suificientl
increased
the

manifold

negative
plre
sure
lowers

Le
tends

towards

atmospheric

pressure
and
the
Automatic

Transmission

vacuum
reaction
increases
since

the

flow

velocity
of
mixture
inside
the

intake
m
mifold
is
slow

Contrarily

when
the

engine
speed
increases
and

the
flow

velocity
of
the

mixture
in

creases
or

when
the
carburetor

is

closed

the
manifold

negative

pressure

increases
Le
tends

towards
vacuum

and
the

vacuum
reaction
is

reduced

Thus
a

signal
to

genera
Ie

hydraulic

pressure
P
rfe

tly
suited
to
the

engine

loading
at

trye
control
valve
is

trans

mitted
from
the
vacuum

diaphragm

and
the
most
suitable

timing
for

speed

change
and
lin
e

pressure
is
obtaine

so

that
the

most

proper
torque
capacity

is

obtained

against
the

transmitting

torque

To
inl
lkc

manifold

AT088

Fig
AT
5
Vacuum

diaphragm

DOWNSHIFT

SOLENOID

T
e

downshift
solenoid
is

of
a

magnetic
type
installed
on

the
left
re
r

portion
of
the
transmission

case
When

a
driver

requires

accelerating
power

and

dePresses
the

accelerator

pedal

down

to
the

stopper
a
kickdown

switch

19ca
ted
in
the

middle
of

the

accelerator

link
is

depressed

by
a

push

rod
he

kickdown
switch

doses
cur

rent
flows
to

the
solenoid

the
sole

noid

push
rod
is

depressed
the
down

shift
valve
of
the

control
valvc
insidc

the

transmi
ssion

case
is

depressed
nd

the

speed
is

changed
forcedly
fmm

3rd
to
2nd
within
a
cerlaill

vehi

cle

speed
limit

Note
Since
theki

kdown
switch

closes
when
the
accelerator

pedal
is

d

epr
ssed
from

7

i
t
I
S
I
6

of
tiie

whole

stroke
the
a
ccel
rator

ped
1

should

be
correctly

adjusted
so
as

arf

rd
a

omplete
stro

e
I

The

arrangement
of
the
swit

h

wries

ccording
m

eI

AT

S
c
C

r
11
I

Kickdown

h

switch

Dowri

shift
solenoid

AT089

Fig
AT
6

Downshifl80lenoid

GOVERNER

VALVE

The

primary
and

secondary

gover

nor
valves
are
installed

separately
on

the

back
of
the
oil
distributor

on
the

transmission

outp
t

sha
ft

tn

y
op

erate

al
the
same

speed
as
th
ar

iJf
tile

output
shaft
thai
is

they
operate
at

a

speed
in

proportion
10

the
vehicle

speed
The
line

press
retis

applied
to

those
valves

s
the

input
from
the

control

valve

through
the

transmission

case
rear

flange
and
oil
distributor

The

governor

pressure
in

proportion

to
the

ouiput
shaft

speed
vehicle

speed
is

led
to
the
shift
valve
ofthe

control
valve

through
the

opposite

route
of
the

output
In

this
manner

speed
change
and
line

pressure
are

controlled

Operation
of

secondary

governor
valve

T
e

secon

ary
valve

is
a

contro

valve

Y
hich
receives

line

pressure

an

cqQ
rols
the

governor

pressu
e

When
the
manual

valve
is
selected

at
D
2

or
l

range
line

pressure

is

applied
t
the
ri

g
sh

aped
area
of

this
valve
from
circuit
I

l
and
this

I

v

Jy
is

depressed
lOW
jr
tI
c

fer

Movemcnt

of
this
valvl
III
a
cr

in

positillll
doses
the
dr
uit

from

Olto

15
while

simultaneously

making
a

sr
rronl
IS
to
Iii
center

d
niin

port
and

press
re

in
tllc
ci
rJ

it

l5j
is

lowered

When

thc
vehicle
is

stopped
1
d

the

cenlrifugal
force
of
this
valve
is
zero

the
v
lve

is
balanced
At
this

poini
a

govcr
lOr

pressurc
y
hich

bal
i1
nced

with

th

spr
ng
force

occurs
on
IS

Wh
n

thc
vehicle
is

st
rted
nd

the

centrifugal

fqr
incre

ses
this
valve

movcs

slightly
10

Ihc
oUlSide
and

as

3

Jit
f
ng
valve

24

1

3

L
l

r

I
Js

I
i

ilr
t
pressure
6
when

shif
ing
from
3rd

to
2nd
at
D

range
Thus
the

throttle
of
line

pressure
6
reduces

the

shock

generated

fro
shifting

A

plug
in
the

SSV
left

end

readjust

the

throttle

piessu
e
I
6
which
varies

depending
on
the

engine
throttle
con

dition
to
a
throttle
pressure
19

suiled
to
the

sp
ed

change
control

Moreover
the

plug
is
a
valve
which

applies
line

P

esspre
13
in
lieu
of
the

throttle

pressure
to
the
SSV
and
the

FSV
when
kickdowri
is

performed

When
the
throttle

pressure
16
is

applied
to
the

left
side
of
this

plug

and
the

plug
is

epressed
toward
the

right
a

slight

space
is
formed
from
the

throttle

pressure
6
10

19
A

throt

tIepressu
19

w
1iFh
is
lower

by
the

pressure
loss

equivalent
to
this

space
is

rH

1

Pressure
Odifier
valve
PMV

I

Compared
to
the

operating

pressure

required
in

starting
th
vehicle
the

ppwer
trimsinitting
capacity
of
the

clutch
that
is

required
operating

pres

sure

may
be

lower
when
the
vehicle
is

once
started
When
the
line

pressure
is

retained
at

a

high
level

up
to

a

high

vehicle

speed
shock

gerieraled
from

the

shirring
increases
arid
the

oil

pump
loss
also
jncrdases
In
order
to

prevent
his
the
t

lrott
le

pressure
must

be
l

hanged
over

with
the

operation
of

the

governor
pressure
15
to
reduce

Ihe
line

pressure
The
PMV
is
used
for

this

purposc
Automatic

Transmission

generated
the

piessure
loss
is
adde
d
to

the

spring
force

and
the

plug
is
lhus

forced

back
from
the

right
to
the

left

When
this

pressure
19
increases
ex

cessively
the

plug
is
further

depressed

toward
the

left

space
from
the
lhrot

tle

pressure
19
to

the
drain
circuit

13

increases
and
the
throttle

press

ure

19
decreases
Thus
the

plug
is

balanced
imd
the
throttle

pressure

19
is

reduced
to
Ii
certain
value

against
the
throttle

pressure
6

Wheri

performing
kickdowri

the

SDV
moves
a

high
line

pressure
is

led

to
the
circuit

19
from
the
line

pressure
circuit

13
which
had

been

drained

the

plug
is
forced
toward
the

left

and
circuit

19
becomes

equal
to

the
line

pressure
13

I

W
15

I

A
TOgS

Fig
iT
13
2nd
3rd

shift
vallJe

I

When

the

governor
pressuie
IS

which
is

applied
to
the

right
side
of

the
PMV
is
low
the
valve
is
forced

toward

the

right
by
the
throttle

ines

sure
16

applied
to
the
area
differ

ence
of
the
value
and
the

spring
foice

and
t

he
circuit

from
circuit

16
to

circuit
18
is
closed
However
when

vehicle

speed
increases
andl
the

gaver

nor

pressure
15
exceeds
a
certain

level
the

governor
pressure
toward

the

left
which
is

applied
to
the

right
side

exceeds
the

spring
force
and
the

throt

tle

pressure
16

toward
thc

right
the

valve
is

depressed
loward
the
lefi

and

the
throttle

pressure
is
led
from
circuit

AT

9
16
to
circuit

18
This
throttle

pressure
18
is

applied
to
the

top
of

the
PRV
and
the
force
of
the

line

pressure
source
7
is
reduced

Contra

rily
when

the
vehicle

speed
decreases

arid
the

governor

ipressure
15
de

creases
the

force
toward
the

fight

exceeds
ithe

governor
pressure
the

valve
is

forced
back
toward
the

right

and
the

throttle

pressure
18
is

drained
to
the

spring
unit

This
valve
is

sWitched
when
the

throttle

pressure
and
the

governor

pressure
are

high
or
when

tIiey
are

both
Tow
i

i
I
11

18
16

n

r

I

I

15

AT099

Fig
AT
14

Pre
ure

modifier
valve

Vacuum
thro
le
valve
VTV

The

vacuum
t
rottle
valve
is
a

regula
tor
valve

whiCh
uses
the
line

pressure
7

for
the

pressure
source

and

regulates
the

throttle

pressure
16

I

which
is

proportioned
t
the

force
of

the

vacuum

diaphragm
The
vacuum

dia

phragm
yories
depending
on
the

engine
throt
le

condition

negative

pressure
in
the

inta
e
line

When
the
line

pressure
7
is

ap

plied
to
the
bottom

through
the

valve

hole
and
the
v

a
ve
is

forced

upward

space
from
the
line

pressure
7
to
the

throttle

pressure
16
is
dosed
and

the

space
from
the
Ihrottle

pressure

16
to

the
drain
circuit
17
is
about

to

open
In

this

operation
the
throttle

pressure
16
becomes
lower
than

the

linep
s

ureY
btthe
p
e
sur

9
iv

alenl
of
the

loss
of

space
and
Ihe

force

depressing
tlie
rod
if
the

vaeuum

diaphragm
is

balanced
wit

Ii
thethrot

tie

pressure
16
a

pplied
upward
tOlthe

bottom

When
the

erigine

torque
is

high
Ihe

negative
pressure
in
the
intake
iirie

rises

tending
ioward

atmospheric

pressure
and
the
force
of
the
rod
to

depress
the
valve
increases
As
a
result

the
valve
is

depressed
downward
the

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

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