1977 DATSUN PICK-UP oil pressure

Engine
Electrical

System

SERVICE
DATA
AND
SPECIFICATIONS

D4A4

06
D4A4
07

Type
D4A6
07
D4A6
08

Firing
order
1
3
4
2
13
4
2

Rotating
direction
Counterclockwise
Counterclockwise

Owen

angle
degree
490
to
550
490

to
550

Point

gap
mm
in
0

45
to
0

55
0
45
to
0
55

0
018
to

0
022
0
018
to
0

022

Point

pressure
kg
lb
0
40

to
0
55
0
40
to
0
55

0

88
to
1

21
0
88
to
1
21

Condenser

capacity
JlF
0
20

to
0
24
0
20

to
0
24

Condenser
isolate
resistance
Mrl
5
5

Cap
isolate
resistance
Mrl
50
50

Rotor
head
isolate
resistance
Mrl
50
50

Cap
carbon

point
length
mm
in
10

0
39
10
0
39

For
Canada

DISTRIBUTOR
California
models

CONSTRUCTION

CHECKING
AND
ADJUSTMENT

CAP
AND

ROTOR
HEAD

AIR

GAP

CONSTRUCTION

In
the
conventional
distributor
the

ignition
liming
is

detected

by
the
cam

and
breaker
arm
while
in
this
transis

tor

ignition
unit
it
is

detected

by
the

reluctor
on
the
shaft
and
the

pick
up

coil

provided
in

place
of
the
breaker

The

pick
up
coil
consists
of
a

magnet

coil
etc
The
amount
of

magnetic
flux

passing
through
the

pole
piece
in
the

coil
is

changed
at
the

moment
the

pole
CONTENTS

EE
33

EE
33

EE
33

EE
33
ADVANCE
MECHANISMS

DISASSEMBLY

ASSEMBLY

SERVICE
DATA
AND
SPECIFICATIONS
EE
33

EE
35

EE
35

EE
36

piece
faces
the

protrusion
of
the

re

luctor

and
then
the
electrical

signal
is

genera
ted
in
the

pick
up
coil

This
electric
signal
is

conducted

into

the
transistor

ignition
unit
which

in

turn
breaks
tI
e

primary
coil
current

running
through
the

ignition
coil
and

generates

high
voltage
in
the

secondary

winding
Also
this
transistor

ignition

EE
33
unit

utilizes
this
electric

signal
to

restore
the

primary
coil
to
the

original

state
after

cutting
off
the

primary

current
for
a
fIXed
time

The

centrifugal
and
vacuum
ad

vance
mechanisms

employ
the
con

ventional
mechanical

type
The
con

tactor
is
used
to
eliminate
vacuum

and

centrifugal
advance

hysteresis

I

Engine
Removal

Installation

ENGINE

REMOVAL
AND
INSTAllATION

REMOVAL

INSTALLATION

ENGINE
MOUNTING
INSULATORS

REMOVAL

It
is
much
easier

to
remove

engine

and
transmission

as
a

single
unit

than

to

remove
them

separately
After
re

moval

engine
can
be

separated
from

transntission

assembly

Notes

a
Be

sure
to
hoist

engine
and

jack
up

transmission
in
a
safe
manner

b
Use

fender
cove
to

protect
vehicle

body

1
Remove

battery

2
Scribe

hood

hinge
location
for

proper
reinstallation
and
remove

hood

Note
Have

an
assistant

help
you
so
as

to

prevent
damage
to

body

3
Drain

radiator
coolant

4

Disconnect

upper
and
lower

radiator
hoses

from

engine

5

Remove

two
oil
cooler
hoses

from
lower

end
of
radiator
Auto

ma
tic
transmission

models

only

6
Remove

radiator

shroud

7

Remove
four

bolts

securing
radia

tor
and

detach
radiator

Note

Always
tighten
securing
bolt
at

upper
right
hand
side

together
with

body
harness

terminal

8

Remove
carburetor
air

cleaner
as

follows

Remove
fresh
air

duct

Remove

hot
air

duct

Loosen
air

cleaner
band

bolt
and
air

cleaner

supporting
bolts

Disconnect
air

cleaner
ta
air

pump

hose

Disconnect
air
cleaner

to
rocker

cover
hose
at

rocker

cover

Disconnect
air

cleaner

to
air

control

valve
hose
California

models

only
CONTENTS

ER
2

ER
3

ER
3
FRONT

INSULATOR

REAR

INSULATOR

TIGHTENING

TORQUE
ER
4

ER
4

ER
4

Disconnect
air

deaner
to

A
B
valve

hose

Disconnect
air

cleaner
ta

vacuum

hoses

Note

Protect
carburetor
from
dust

and

foreign
matter

by

placing
cover

over
air
inlet

opening

9

Disconnect

fuel

pump
to
fuel

fdter
hose
and
return

hose

10

Disconnect
carbon
canister

hose

on

engine
side

II

Disconnect
air

pump
air

C1eaner

to
al

p

p
hose

12

Disconnect

following
cables

wires

and
hoses

Engine
ground
cable

Accelerator
wire
at

carburetor

High
tension

cable
between

ignition

coil

and
distributor

Wire

to
distributor
at

body
ter

minal

Wire
to

oil

pressure
switch

Wires
to
thermal

transmitter

Wires
to

B
C

p
D
cut
solenoid

Non
California

models

only

auto

choke
heater
and

anti

dieseling

solenoid

Wires

to
alternator

Wires
to
starter

motor

Heater
inlet
and
outlet

hoses
if
so

equipped

Vacuum
hose
of

Master
Vac
at
in

taJce
manifold

Wires
for

back

up

lamp
switch

Cable
to

speedometer

13

Remove
transmission

control

linkage
from

transmission

Manual

transmission
models

I

Detach
rubber
boot

2
Remove
E

ring
and
control

lever

pin
from

transmission

striking
rod

guide
and

remove
control
lever

ER
2
Fig
ER
l

Automatic

transmission
models

I

Disconnect

selector

range
lever

from
manual
shaft

2
Disconnect
wires

at
inhibitor

switch
and

down
shift
solenoid

14
Air

conditioner

equipped

models
need

following

procedures

1
After

removing
flexible

hose

support
remove
four

comi
ressor

se

curing
bolts

Then
move
the

com

pressor
to

battery

support

2

Remove

vacuum
hoses
of

F
LC
D
solenoid
valve

3
Remove
F
LC

D
actuator

15
Remove
two
bolts

securing

clutch

operating
cylinder
Then
dis

connect

operating
cylinder
and

flexi

ble
tube

as
an

assembly

Manual

transmission

models

only

16
Disconnect
front

exhaust
tube

from
exhaust
manifold

17
Remove

propeller
shaft

I

Disconnect

propeller
shaft

center

bearing
bracket
from

third

crossmember

2

Disconnect

propeller
shaft
from

companion
flange
of
differential

carrier

3
Remove

propeller
shaft
from

transmission

and

plug

up
rear
end
of

extension

housing
of

transmission
to

prevent
oil

leakage

18
Attach
a
suitable
wire

or
chain

to
lift

engine

19
Remove

front

engine
mounting

bolts

at

engine
mounting
front

sup

port

l
t

tJ
I

P

o

CUll

Fig
CL
9

Lubricating
poinu
of

withdrawal
lever
and

front
cover

4

Contact
surfaces
of
transmission

main

drive

gear
splines
lithium
base

grease
including
molybdenum
disul

phide

Note

Very
IIIIJllII
amount
of

grease

should
be
ated
to
the
above

points
If
too
much
iubricant
is

applied
it
will
run
out
on
the

friction

plates
when
hot

resulting

in
d

gi
dutch
disc

facings

3
Install
retainer

spring
to
with

drawal
lever
Fit
holder

spring
to

release

bearing
and
sleeve

assembly

then
assemble
withdrawal
Iever
and

bearing
sleeve
as
a
unit
Install
this

assembly
on

transmission
case
Then

install
dust

cover

Pilot

bushing

Before

installing
a
new

bushing

thoroughly
clean

bushing
hole
Install

bushing
in
crankshaft

using
a
soft

hammer

Bushing
need
not
be
oiled

INSPECTION

Wash
all
the
disassembled

parts

except
release

bearing
and
disc
assem

bly
in
suitable

cleaning
solvent
to

remove
dirt
and

grease
before

making

inspection
and

adjustment

Flywheel
and

pressure
plate

Check
friction
surface
of

flywheel

and

pressure
plate
for

scoring
or

roughness
Slight
roughness
may
be

smoothed

by
using
fme

emery
cloth

If
surface

is

deeply
scored
or

groov

ed
the

part
should
be

replaced

Clutch
disc
at
llembly

Inspect
clutch
disc
for

worn
or

oily

facings
loose

rivets
and
broken

or

loose

torsional

springs
CLUTCH

I
If

facings
are

oily
the
disc
should

be

replaced
In
this
case

inspect
trans

mission
front
cover
oil
seal

pilot

bushing
engine
rear
oil
seals
and
other

points
for
oil

leakage

2
The
disc
should

also
be

replaced

when

facings
are
worn
locally
or
worn

down
less
than
0
3
mm
0
0118
in

at

revels
See

Figure
CL
IO

DePth

ll
I

gauge

II

1
i
h

1

j1
t

f

Above

0
3
rom

10
012
in

CL089

Fig
CL
I0
Me
JIuringclutch

lining

3
Check
disc

plate
for
runout
when

ever
the
old
disc
or
a

new
one
is

installed

4
If

runoutexceeds
the

specified

value
at

the
outer
circumference
Ie

place
or

repair
disc
See

Figure
CL
II

Runou

t

0
5
mm
0
020
in

total
indicator

reading

R

from
the

hub
center

107
5
mm
4

23
in

CL112

Fig
CL

ll

MeOlUring
disc
runout

5
Check
the
fit
of
disc

hub
on

transmission
main
drive

gear
for

smoothly
sliding
If

splines
are
worn

clutch
disc
or
main
drive

gear
should

be

replaced
that

is
backlash
exceeds

0
4

mm
0
016
in

at
the
outer

edge
of

clutch
disc

Clutch

cover

assembly

I
Check

the
end
surface
of

dia

phragm
spring
for
wear

CL
4
If
excessive
wear
is

found

replace

clu
tch
cover
as
an

assembly

2
Measure
the

height
of

diaphragm

spring
as
outlined
below

See

Figure

CL
12

a
Place
Distance
Piece
ST20050100

on
Base
Plate
ST20050010
and

then

tighten
clutch
cover

assembly

on
the
base

plate
by
using
Set
Bolls

ST20050051

b
Measure

diaphragm
spring
toe

height
A

at
several

points
with
a

vernier

caliper

depth
gauge

STl0050100

rJrf
I
Tl

05001O

f

7

C
L23

STl005Q051

Fig
CL
12

Me
uring
the

height
of

diaphragm
pring

If
the

height

A
of

spring
end
is

beyond
the

specified
value
of
33
to
35

mm
1
23

to
1
38
in

adjust
the

spring

height
with

Diaphragm
Adjusting

Wrench
ST20050240
See

Figure

CL

13

If

necessary
replace
clutch

cover
as

an

assembly
Also
unevenness
of
dia

phragm
spring
toe

height
should
be

less
than
05
mm
0
020
in

ST20050240

CL152

Fig
CL
13

AdjlUting
the

spring
height

3

Inspect
thrust

rings
for
wear
or

damage
As
these

parts
are
invisible

from
outside
shake
cover

assembly
up

and
down
to
listen
for

chattering

noise
or

lightly
hammer
on
rivets
for
a

slightly
cracked
noise

Any
of
these

noises
mean

requirement
for

replace

ment
as
a

complete
assembly

CLUTCH

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Probable
cause
and

testing

Clutch

slips
Corrective
action

Slipping
of
the

clutch

may
be

noticeable
when

any
of
the

following
symptoms
is

encountered

during
operation

I
Vehicle
will

not

respond
to

engine

speed
during
acceleration

2
Insufficient
vehicle

speed

3
Lack
of

power
during
uphill
driving

Some
of
the

above
conditions
are
also

experienced
when

engine

problem
is

oc

urring
First

de
tennine
whether

engine
or
clutch
is

causing
the

problem

If

slipping
clutch
is

left
unheeded
wear
and
or

overheating
will
occur
on
clutch

facing
until
it
is

no

longer
serviceable

TO
TEST
FOR
SLIPPING
CLlJfCH

proceed
as
follows

During
upgrade
travelling
run

engine
at

about
40
to
50
km

h
25
to
31

MPH
with

gear
shift

lever
in

3rd

speed
position
shift
into

highest
gear
and
at
the
same
time

rev

up
engine
If
clutch

is

slipping
vehicle
will
not

readily

respond
to

depression
of
accelerator

pedal

Clutch

facing
worn

excessively

Oil
or

grease
on
clutch

facing

W

r
d
clut
h
cov
r

pressure
plat
Replace

Replace

tpa
o
e
lace

Dragging
clutch
is

particularly
noticeable
when

shifting
gears
especially
into

low

gear

TO
TEST
FOR
DRAGGING
CLlJfCH

proceed
as
follows

I
Start

engine
Disengage
clutch
Shift
into

reverse

gear
and
then
into
Neutral

Gradually

increase

engine
speed
and

again
shift
into
reverse

gear
If
clutch
is

dragging
gear
grating

is

heard
when

shifting
from
Neutral
into

Reverse
Clutch

drags

2

Stop
engine
and
shift

gear
Conduct
this
test
at
each

gear
position

3
Gears

are
smoothly
shifted
in

step
2
but

drag
when

shifting
to
1st

speed
position
at

idling

a
If

dragging
is
encountered
at
the
end
of

shifting
check
condition
of

synchro

mechanism
in
transmission

b
If

dragging
is
encountered
at
the

beginning
of

shifting
proceed
to

step
4

below

4
Push

change
lever
toward
Reverse
side

depress
pedal
to
check
for
free
travel

a

If

pedal
can
be

depressed
further
check
clutch
condition

b
If

pedal
cannot
be

depressed
further

proceed
to

step
5
below

5
Check
clutch
control

pedal
height
pedal
free
travel
withdrawal
lever

play
etc

If
no
abnonnal

condition
exists
and
if

pedal
cannot
be

depressed
further
check
clutch

condition

Clutch
disc
runout
or

warped

Wear

or
rust

on
hub

splines
in
clutch
disc

Diaphragm
spring
toe

height
out
of
ad

justment
or
toe

tip
worn

Worn
or

improperly
installed

parts

CL10
Repair
or

replace

Clean
and
lubricate
with

grease
or

replace

Adjust
or

replace

Repair
or

replace

Condition

Clutch
chatters

Noisy
clutch

Clutch

grabs
CLUTCH

Probable
cause
and

testing
Corrective
action

Clutch

chattering
is

usually
noticeable
when
vchicle
is

just
rolled
off
with
clutch

partially

engaged

Weak
or
broken
clutch
disc
torsion

spring

Oil
or

grease
on
clutch
facing

Clutch

facing
out
of

proper
contact
or

clutch
disc

runout

Loose
rivets

Warped

pressure
plate
or
clutch
cover

surface

Unevenness
of

diaphragm
spring
toe

height

Loose

engine
mounting
or
deteriorated

rubber

A
noise
is
heard
after
clutch
is

disengaged

Damaged
release

bearing

A
noise
is

heard
when
clutch
is

disengaged

Insufficient

grease
on
the

sliding
surface

of

bearing
sleeve

Clutch
cover
and

bearing
are
not
installed

correctly
Replace

Replace

Replace

Replace

Repair
or

replace

Adjust
or
replace

Retighten
or

replace

I
Replace

Apply
grease

Adjust

A
noise
is
heard
when
vehicle
is

suddei11y
staited
off
with
clutch

partially
engaged

Damaged
pilot
bushing

I
Replace

When

grabbing
of
clutch
occurs
vehicle
will
not
start
off

smoothly
from
a

standing
start
or

clutch
is

engaged
before
clutch

pedal
is

fully

depressed

Oil
or

grease
on
clutch

facing

Clutch

facing
worn
or
loose
rivets

Wear
or
rust
on

splines
in

drive
shaft
and

clu
tch
disc

Warped
flywheel
or

pressure
plate

Loose
mountings
for

engine
or

power

train
units

CLll
Replace

Replace

Clean
or

replace

Repair
or

replace

Retighten

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

the

space
from
I

to
IS
increases

space
from
15
to
the

drain

port

simultaneously
decreases
As
a

resull

governor
pressure
of

15
increases

and
the

governor
pressure
is
balanced

with
the
sum
of

centrifugal
force
and

spring
force
The
governor

pressure

thus
changes
in

response
to
the
vehicle

speed
change
centrifugal
force

Operation
of

prlmar

governor
valve

The
valve
is

an
ON
OFF

valve

which
closes
the

governor

pressure

IS

regulated
by
the

secondary

gover

nor
valve
when
the
vehicle
reaches
the

minimum

speed
and
when
the
vehicle

speed
exceeds
a
certain

level
the

governor
opens
and
forwards

the

gov

ernor

pressure
15
to
the
control

valve

When
the
vehicle
is

stopped
the

governor

pressure
is
zero
However

when
the

vehicle
is

running
slowly

this
valve

is

depressed
to
Ihe

center

and
the

groove
to
15
is
closed
since

the

governor
pressure
applied
to
the

ring

shaped
area
is

higher
than
the

centrifugal
force
of
this
valve
When

the

governor
speed
exceeds
a
certain

revolution
the

governor
pressure
in

the
circuit
15
also
increases
How

ever
as
the

centrifugal
force

increases

and
exceeds
the

governor
pressure
this

valve
moves
toward
the
outside
and

the

governor
pressure
is

transmitted
to

the
circuil
5

Two
different
valves
are

employed

in

the

governor
so
that
it
will
inde

pendently
control
the

speed
at

high

and
low

speeds
That
is
within
the
low

speed

range
the

governor

pressure
is

not

generated
because
of
the

primary

valve
whereas
at
the

high
speed
range

above
the

breaking
point

governor

pressure
is

regulated
by
the

secondary

valve

The

breaking
point
is
the

point
at

which

the
function
of

one
of
the

governor
is
transferred
to

the
other

as
the

speed
changes
from
the

low

speed
to
the

high

speed
range
Automatic
Transmission

To
onlml

valve

l
Governor

pre
S1I
1I5
j

I

Q
J
J

f
1

1

CID

l

l
m

Line

pressure
t
D@

I

Primary
governor

2
Secondary

governor

3
Governor
valve

body
AT090

4

Oil
di
lributor

5

Output
sh
lft

Fig
AT
7
Cr05s
sectionallliew

of

governor

CONTROL

VALVE
ASSEMBLY
Ai09

Fig
AT

S

Output
shaft
with

oil

distributor
and

overnor

r

@

@
0

aBUlllI8

iUQlli
V

JlAU

I
Oil
distributor

2
Governor
nlve

body
A

T092

3

Primary
governor

valve

4

Secondary
governol

valve

Fig
A
T

9

Exploded
view

of
governor

Flow

cbar
of

control
valve

system

Oil
from

pump

Regulator
valve

1

I
i

j

Throttle
valve

I
I
l

Manual
valve
I

I

I

I

I

I

I

L

n
L

j
Speed
change

valve
I

I

t

t

I

I

I

I

I

I
Governor
I

I
valve

I

I

I

L
L

1
II
Auxiliary
valve

Line

pressure

j
Clutch
and
brake

The
control
valve

assembly
receives

oil
from
the

pump
and
individual

signals
from
the
vacuum

diaphragm

and
transmits
the
individual

line

pres

sures
to
the

transmission
friction
ele

ment

torque
converter
circuit
and

lubricating
system
circuit
as

outputs

More

specifically
the
oil
from
the
oil

pump
is

regulated
by
the

regulator

valve
as
line

pressure
build

up
the
line

pressure
is

fed
out
from

the
control

valve

assembly
through
various

direc

AT
6
tion

changeover
valves

including
ON

OFF
valve
and

regulator
valves
are

newly
reformed
to
a
throllle

system

oil

pressure
and

operate
other
valves

Finally
the
line

pressure
is

transmilled

to

the

required
dutch
or

brake
servo

pisJon
unit
in

response
to
the
individu

af

running
conditions
after
re

ejving

signals
from
the

va
uum

diaphragm

downshift
solenoid

governor
V
dlvc

and
or
manual

linkage