1977 DATSUN PICK-UP oil change

Emission
Control

System

EARLY

FUEL

EVAPORATIVE

SYSTEM
E

F
E

DESCRIPTION
spring
and

counterweight
which
are

assembled
on
the

valve
shaft

projecting

to
the

rear
outside
of
the
exhaust

manifold
The

counterweight
is
se

cured
to
the
valve
shaft
with

key
bolt

and

snap
ring
EC
4
A

control
valve
welded
to

the

valve
shaft
is

wtalled
on
the

exhaust

manifold

through

bushing
This
con

trol

valve
is

called
Heat

control

valve
The
heat
control

valve
is

ac

luated

by
the

coil

spring
thermostat
Construction
of
the

early
fuel

evap

orative

system
is

shown
in

Figure

r
I

1

@

rW

9

Sc
w

10
Thennostat

spring

11

Coil
spriiig

12
Control
valve
shaft

13
Heat
control

valve

14

Bushing

15

Cap

16
Exhaust
manifold
1
Intake
manifold

2
Stove

gasket

ManifoktstOve

4
Heat
shield

plate

5

Snap
ring

6

Counterweight

7

Key

g

Stoppel
pin

EC532

Fig
EC
4
Early
Fuel

Evaporutive
tem
E
F
E

The

early
fuel

evaporative
system
is

provided
with
a
chamber
above

a

manifold
stove
moonted
between
the

intake
and
exhaust

manifolds

During

engine

warming
up
air
fuel
mixture
in

the

carburetor
is

heated
in
the
cham

bet

by
exhaust

gases
This
results
in

improved
evaporation
of

atomized
fuel

droplets
in
the
mixture
and
in

smaller

content
of

hydrocarbons
He
in
the

exhaust

gas
especially
in

cold
weather

operation

The
exhaust

gas
flow
from
the

engine
is

obstructed

by
the
heat
con

trol

valve
in
the

exhaust
manifold
and
is

changed
in

direction
as
shown

by

the
solid

lines
in

Figure
EC
4
The

exhaust

gas
heats
the
manifold
stove

Open
close

operation
of
the

heat

control
valve
is
controlled

by
the

counterweight
and
thermostat

spring

which
is
sensitive
to
the

ambient
tem

perature
around
the

exhaust
manifold
With
this
condition
the

heat
control

valve
is
in

the

fully
closed

position

obstructing
the
flow
of

exhaust

gas
As

engine
tempera
lure

goes
up
and

the

ambient

temperature
becomes

high

enough
to
actuate
the
thermostat

spring
the

counterweight
begins
to

rotate
clockwise
and

again
comes
into

con

tact
with

the

stopper
pin
With
this

condition
the

heat
control
valve
is
in

the
full

open
position
and
exhaust

gas

passes
through
the
exhaust
manifold
as

shown

by
the
dotted

lines
in

Figure

EC
4
without
heati

ng
the
manifold

stove
OPERATION

The

counterweight
rotates
counter

clockwise
and

stops
at

the

stopper
pin

mounted
on
the
exhaust

manifold

while

the

engine
temperature
is
low

EC
6

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

Inspection

Note
To
clean
or
wash
all

parts
of

master

cylinder

operating
cylinder

and

piping
clean
brake
fluid
must

be
used
Never
use
minera10ils
llUch

as

gasoline
and
kerosene
It

will

ruin
the
rubber

parts
of
the

hydrau

lic

system

I

Check
cylinder
and

piston
for

uneven
wear
or

damage
and
if
neces

sary
replace

2
If
the
clearance
between

cylinder

and

piston
is

more
than

0
15
mm

0
0059
in

replace
cylinder

3

Renew

piston
cup
when
dis

assembled
It
must
also
be

replaced

when
wear
or
deformation
due
to

fatigue
or

damage
is

found

4

Damaged
dust
cover
oil
reservoir

or

cap
should
be

replaced

Return

spring
and
valve

spring
must

also
be

replaced
when

they
are
broken

or
weak

5

Replace
clutch
hose
and
tube
if

any
abnormal

sign
of

damage
or
de

fro

ti

n
is
found

OPERATING

CYLINDER

Removal
and

installation

Removal

1

Detach
clutch
hose
from

operat

ing
cylinder

2
Remove
two
bolts

securing
op

erating
cylinder
to
clutch

housing

Installation

Install

in
the
reverse
order
of
re

moval

Observe
the

following
instructions

Bleed
air

thoroughly
from
clutch

hydraulic
system

2
Do
not

install
return

spring
or

clutch
will

not
be

disengaged

properly

Tightening
torque

Operating
cylinder
securing
bolt

2
5
to
3
5

kg
m

18
to
25
ft
lb

Bleeder
screw

0
7
to
0
9

kg
m
5
1

to
6
5
ft
Ib

Clutch
hose
connector

1
7
to

2
0

kg
m
12
to
14
ft

b
CLUTCH

Disassembly
and

assembly

Disassembly

1
Remove

push
rod
with
dust

cover

2
Remove

piston
assembly
and

pis

ton

spring

3
Remove

bleeder
screw

1
6

Cl11B

5

Piston

cup

6

Operating
cylinder

7
Bleeder
screw
1

Push
rod

2
Dust
cover

3
Piston

spring

4

Piston

Fig
CL
20

Exploded
view

of

operating
cyUnder

Assembly

Assemble
in
the

reverse
order
of

disassembly
Closely
observe
the
fol

lowing
instructions

1

Prior
to

assembly

dip
piston
cup

in

clean
brake
fluid

When

installing
cup
pay
particular

attention
to
its
direction

2

Dip
cylinder
and

piston
in
clean

brake
fluid
before

assembly

Notes

a
Be

sure
to
install

piston
assembly

with

piston
spring
in

place

b
The
clutch

operating
cylinder
is

available
in
both
NABCO
make
and

TOKICO
make
There
is
no
inter

changeability
of

repair
kits
or
com

ponent
parts
between
NABCO
and

TOKICO
makes

When

replacing
the

repair
kit
or

component
parts
ascertain
the

brand
of
the
clutch

operating
cyl

inder

bndy
Be
sure
to
use

parts
of

the

same
make

as
the
former
ones

Inspection

Visually

inspect
all
disassembled

parts
replacing
those
found
worn
or

rl

Q
damaged
too

badly

beyond
speci

fications

BLEEDING
CLUTCH

SYSTEM

The

hydraulic
clutch

system
must

be
bled
whenever
clutch
line
has
been

disconnected
or
air

has
entered
it

When

pedal
action
has
a

spongy

feeling
it
is
an
indication
that
air
has

entered
the
system

Bleeding
clutch

system
is

an
es

sential

part
of

regular
clutch
service

I

Remove
reservoir

cap
and

top
up

with
recommended
brake
fluid

2

Thoroughly
clean
mud
and
dust

from
bleeder
screw
of

operating
cyl

inder
so
that
outlet
hole
is

free
from

any
foreign
rnaterial
Install
bleeder

hose

vinyl
hose
on
bleeder
screw

Place
the
other
end
of
it
in

a
clean

container

3
Have
a
co
worker

depress
clutch

pedal
two
or

three
times
With
clu
tch

pedal
depressed
fully
loosen
bleeder

screw
to
bleed
air
out
of
clutch

sys

tern

4
Close
bleeder
screw

quickly
as

clutch

pedal
is

on
down
stroke

5
Allow
clutch

pedal
to
return

slowly
with
bleeder
screw
closed

6

Repeat
steps
4
and
5
until

no
air

bubble
shows
in

the

vinyl
hose

7

Operate
clutch
several
times

then
check
connections
for
external

hydraulic
leaks

Notes

a
Brake
fluid

containing
air
is
white

and
has
visible
air
bubbles

b
Brake
fluid

containing
no
air
runs

out
of
bleeder
screw
in
a
solid

stream
without
air
bubble

c

Pay
close
attention
to
clutch
fluid

level
in
reservoir

during

bleeding

operation

d
Do
not

reuse
brake
fluid
drained

during
bleeding
operation

e
Exercise
care
not
to

splash
brake

fluid

on
exterior
fInish
as
it
will

damage
the

paint

f
Pour
brake
fluid
into
reservoir

up

to

specifIed
level

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

Note
Prior
to

assembling
reverse
fork

rod
instaU
two
2
interlock
balls

into

adapter

piate
as
shown
in

Figure
MT
I6

6
Install
check
ball
and
check

ball

spring

Apply
sealant
to
check

ball

plug

and
install
it
in

place

Align
notch
in

reverse
fork
rod
with

check
ball

See

Figure
MT
52

TM369

Fig
MT
52

Installing
reverse

fork

rod

7

Torque
each
check

ball

plug
to

1

9
to

2
5

kg
m

14
to
18
ft
Ib

Note
BaD

plug
for
ht
2nd
fork
rod

is

longer
than
those

for
rev
shift

fork

rod
and

3rd
4th
fork
rod

8

Apply
gear
oil
to
all

sliding
sur

faces

and
check
to
see
that
shift

rods

operate
correctly
and

gears
are

engaged

smoothly

TRANSMISSION

ASSEMBLY

Tran
mis
lon
ea

mbly

1
Clean

mating
surfaces
of

adapter

plate
and
transmission

case

Apply
sealant

to

mating
surfaces

of

adapter
plate
and

transmission
case

2

Slide
transmission

case
onto

adapter
plate
by

lightly
tapping
with

a

soft
hammer
until
case

bears

against

adapter
plate

Carefully
install
main
drive

bearing

and
countershaft
front

bearing

Make

certain
that
mainshaft

rotates

freely

3
Fit

main
drive

bearing

snap
ring

to

groove
in
main

drive

bearing

by

using
Expander
See
Figure
MT
53
Manual
Transmission

Fig
MT
53

Fitting
main
drive

bearing
snap
ring

R
ar
xt

nslon
ass

mbly

I
Clean

mating
surfaces
of

adapter

plate
and

fear
extension

Apply
sealant
to

mating
surfaces

of

adapter
plate
and

rear
extension

2
With
fork

rods
in

their
neutral

positions

graduaUy
slide
rear
exten

sion

onto

adapter
plate

making
sure

that

speed
change
cross

lever

engages

with

fork

rod
brackets

correctly

3

Install
washers
and

through
bolts

and

torque
to
1

6
to

2
1

kg
m

12
to

15
ft
lb

Available

shim
Front
eov
r
s

mbly

I

Select
countershaft
front

bearing

shim
as
follows
See

Figure
MT
54

1
Measure

depth
A
from

front

end
of
transmission
case
to

counter

shaft
front

bearing

2
Select
a
shim
of
thickness
A

measured

D

A

JJ
ID

@

2J1

I

Transmission

case

2

Countershaft

front

bearing

3

Countershaft

4

Shim

TM371

Fig
MT
54

Selecting
countershafl

front
bearing
shim

No

A
Countershaft
front

rnm
in

bearing
shim
mm
in

I
2
92
to
3

01
0
1150

to
0

1185
0

6
0
024

2

3
02
to

3
11

0
1189
to
0
1224

0
5
0
020

3
3
12

to
3
21
0

1228
to
0

1264
0
4

0
016

4
3
22
to

3
3
I

0
1268
to
0

1303
0
3
0
012

5

3
32
to
3

41
0

1307

to
0
1343

0
2
0
008

6
3
42

to
3
5
I

0

1346
to
0

1382
0
1
0
004

7
3

52
to

3
61
0

1386

to
0
1421

8
3
62

to
3
71
0
1425
to
0

1461

2
Clean

mating
surfaces
of
front

cover
and

transmission
case

Apply
grease
to
shim
selected
to

retain
it
on
front
cover
install
front

cover
to
transmission
case
with

gasket

in
place

Install

through
bolts
with

washers

under
them
and

tighten
to
1

6
to
2
1

kg
m
12

to
15
ft
lb

torque

Apply
sealant
to
threads
of

through
bolts
before
installation

MT13
3

Install

speedometer
pinion
assem

bly
on
rear
extension

After

making

Sure
that

lock

plate
is

lined

up
with

groove
in

speedometer
pinion
sleeve

install

through
bolts
and

torque
to
0
4

to
0
5

kg
m
3

to
4
ft

lb

4

Install
back

up
lamp
switch
and

torque
to
2

0
to
3

0

kg
m

14
to
22

ft
lb

Be
sure
to

apply
sealant
before

installation

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

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