torque DATSUN 210 1979 Manual PDF
Page 255 of 548
Automatic
Transmission
HYDRAULIC
CONTROL
UNIT
AND
VALVES
The
hydraulic
or
a
tomatic
control
system
is
comprised
of
four
4
basic
groups
the
pressure
supply
system
the
pressure
regulating
system
the
flow
control
valves
and
the
friction
elements
PRESSURE
SUPPLY
SYSTEM
The
pressure
supply
system
consists
of
a
gear
type
oil
pwnp
driven
by
the
engine
through
the
torque
converter
The
pump
provides
pressure
for
aU
hydraulic
and
lubrication
needs
PRESSURE
REGULATOR
VALVES
The
pressure
regulating
valves
con
trol
the
output
pressure
of
the
oil
pump
Pre
ure
rellulator
valve
The
pressure
regulator
valve
con
trois
mainline
pressure
based
on
throttle
opening
for
the
operation
of
the
band
clutches
and
brake
Governor
valve
The
governor
valve
transmits
re
gulated
pressure
based
on
car
peed
to
the
shift
valves
to
control
upshifts
and
downshifts
Vacuum
throttle
valve
The
vacuum
throttle
valve
transmits
regulated
pressure
based
on
engine
load
vacuum
This
pressure
controls
the
pressure
regulator
valve
Also
this
pressure
is
applied
to
one
end
of
the
shift
valves
in
opposition
to
governor
pressure
which
acts
on
the
other
end
of
the
shift
valves
controlling
upshift
and
downshift
speeds
FLOW
CONTROL
VALVES
Manual
valve
The
manual
valve
is
moved
manual
Iy
by
the
car
operator
to
select
the
different
drive
ranges
1
2
ShHt
valve
The
1
2
shift
valve
automaticaIly
shifts
the
transmission
from
first
to
second
or
from
second
to
first
depend
ing
upon
governor
and
throttle
pres
sure
along
with
accelerator
position
solenoid
downshift
valve
See
Hy
draulic
Control
Circuits
Drive
2
2
3
ShHt
valve
The
2
3
shift
valve
automaticaIly
shifts
the
transmission
from
second
to
top
gear
or
from
top
to
second
de
pending
upon
governor
and
throttle
pressure
or
accelerator
position
sole
noid
downshift
valve
See
Hydraulic
Control
Circuits
Drive
3
Range
2
3
Tlmlnll
valve
For
2
3
shifts
a
restrictive
orifice
slows
the
application
fluid
to
the
front
clutch
while
the
slower
reacting
band
is
allowed
to
release
This
prevents
a
hard
2
3
or
3
2
shift
Under
heavy
load
however
the
engine
will
tend
to
run
away
during
the
2
3
or
3
2
shift
pause
therefore
a
2
3
timing
valve
using
throttle
and
governor
pressure
is
used
to
bypass
the
restrictive
orifice
during
such
heavy
load
conditions
Solenoid
down
hHt
valve
The
solenoid
downshift
valve
is
activated
electrically
when
the
ac
celerator
is
f1oor
d
causing
a
forced
downshift
from
top
to
second
top
to
first
or
second
to
first
gear
depending
upon
car
speed
governor
pressure
AT
3
Pre
ure
modified
valve
The
pressure
modifier
valve
assists
the
mainline
pressure
regulator
valve
in
lowering
mainline
pressure
during
high
speed
light
load
conditions
such
as
steady
speed
cruise
Governor
pres
sure
working
against
a
spring
opens
the
valve
which
aUows
modified
throt
tle
pressure
to
work
against
the
pres
sure
regulator
valve
spring
lowering
mainline
pressure
Lower
operating
pressure
under
light
load
reduces
oil
temperature
and
increases
transmis
sian
life
Throttle
back
up
valve
The
throttle
back
up
valve
assists
the
vacuum
throttle
valve
to
increase
line
pressure
when
the
manual
valve
is
shifted
either
to
2
or
I
range
Second
lock
valve
The
second
lock
valve
is
used
to
bypa
the
1
2
shift
valve
to
maintain
the
band
apply
pressure
in
2
posi
tion
The
valve
is
also
used
as
an
oil
passage
for
the
1
2
shift
valve
band
apply
pressure
in
D2
D3
and
12
Range
CLUTCHES
AND
BAND
SERVOS
The
servo
pistons
of
the
clutches
low
reverse
brake
and
band
are
moved
hydraulically
to
engage
the
clutches
brake
and
apply
the
band
The
clutch
and
brake
istons
are
released
by
spring
tension
and
band
piston
is
released
by
spring
tension
and
hy
draulic
pressure
Page 257 of 548
OIL
CHANNEL
IDENTIFICATION
The
circuit
numbers
shown
in
each
Hydraulic
Control
Circuit
are
classified
as
follows
according
to
the
function
Pressure
source
of
the
line
7
Operating
line
pressure
for
friction
elements
I
2
3
4
5
6
g
9
10
11
12
Auxiliary
line
pressure
13
Torque
converter
pressure
14
Governor
pressure
15
Throttle
system
pressure
16
17
18
19
Oil
pump
discharge
hole
7
f
Torque
converter
pressure
14
Rear
clutch
pressure
1
Front
clutch
pressure
11
W
h0i1
pu
6
suction
hote
e
8
IIlIlJJIII
Automatic
Transmission
L
f
AT106
Fig
AT
5
Oil
Channela
in
Cou
Front
Face
lo
o
o
0
Oil
pump
discharge
hole
7
Governor
pressure
15
1
h
Torque
converter
I
pressure
14
0
0
Servo
release
Rear
clutch
l
press
re
10
r
L
Governor
reed
pressure
1
pressure
1
Servo
tlghtemng
li
nb
o
0
pressure
9
r
Front
clutch
fI
Low
reverse
brake
pressure
12
pressure
11
U
0
111
1
1
P
u
n
e
AT107
ATlOS
Fig
A
T
4
Oil
Channell
in
Oil
Pump
Fig
A
T
6
Oil
Channell
in
Cou
Fac
MECHANICAL
OPERATION
In
the
3N71B
automatic
transmis
sion
each
part
operates
as
shown
in
the
following
table
at
each
gear
select
position
RanKe
Cm
ratio
Clutch
Low
A
Front
Rear
brake
One
w
y
dutch
Parkin
pa
l
Band
servo
Operation
Release
Park
on
on
Reftrst
2
182
on
on
on
Neutral
Dl
Lo
2
458
on
on
Drift
02
Second
1
458
on
03
Top
1
000
on
on
on
2
Second
1
4
8
on
on
12
Second
1458
on
on
Low
2
4
8
on
on
Note
The
low
brake
is
applied
in
11
raiW
to
prevent
free
whee6ng
when
coasting
and
aIlows
engine
braking
AT
5
Page 260 of 548
RANGE
REVERSE
Po
r
flow
With
the
selector
lever
in
R
range
the
front
clutch
is
applied
to
transmit
clockwise
engine
torque
through
the
connecting
shell
to
the
sull
gear
The
clockwise
otation
of
the
sun
gear
causes
the
planet
gears
to
rotate
counterclockwise
With
the
low
and
reverse
brake
holding
the
rear
planet
carrier
the
rear
internal
gear
splined
to
the
output
shaft
turm
counterclockwise
in
a
reduction
ratio
ofapproximately2
18
to
1
Fluid
flow
Manual
Valve
4
Automatic
Tninsmission
Front
gear
set
Rear
gear
ell
Output
Input
throush
front
clutch
Held
by
low
A
reverse
brake
AT329
lW
w
Y
Front
clutch
Rear
clutch
Low
and
reverse
brake
Brake
band
servo
On
way
clutch
5
Throttle
Back
up
Valve
Low
A
reverse
brake
ON
Downshift
Valve
1st
2nd
Shift
Valve
12
6
L
Pressure
Regulator
Valve
2nd
3rd
Shift
Valve
10
AT
8
AT085
ON
OFF
ON
OFF
Preuwe
release
o
ernmnin
F
AT
9
M
hanical
Operation
during
R
Range
13
2nd
3rd
Shift
Valve
L
1st
2nd
Shift
Valve
I
Throttle
Back
up
Valve
y
Low
Reve
Brake
Band
Servo
Release
Side
11
Front
Clut
h
I
Page 261 of 548
Automatic
Transmission
R
ren
e
Rever
Torque
con
r1
ril
j
j
I
f
I
12
C
I
J
111
x
J
0
8
Q
I
II
lr
Vacuum
Throttl
I
old
I
10
J
f
k
JP
L
u
I
lJ
El
J
U
I
II
O
co
l
chell
01
TO
I
drain
fol
il
Xl
tJj
1
J
l
2nd
3rd
Ii
minQ
x
U1
1
21
1
1C
ll
IIF
li@S
OC
II
to
0
r
6
9r3
Q
rm
g
L
1
u
iii
uLrt
23
r
t
@
PRND2
I
I
x
moo
la
OlenOid
Oil
cooler
1Rear
lubr
c
otion
f
L
ohl
r
Front
u
J
I
@2nd
3
Shift
vol
a
IS
I
12
u
l
r
I
3
w
q
r
4
I
l
Secondory
Qo
rnar
01
Primarf
Qo
i1lr
lol
Note
Mork
d
X
Qr
droin
j
Lin
prUltfrt
Go
nor
tced
r
rr
uur
J
G
0
1
1
101
pr
L
J
3
J
Torqu
can
tar
P
Urt
Tn
rotU
pr
ur
AT456
Fig
AT
10
Oil
Pr
lSure
Circuit
Diagram
R
range
Reverse
AT
9
Page 264 of 548
DI
RANGE
LOW
GEAR
Po
r
flow
With
the
shift
selector
in
0
low
gear
engine
torque
is
traJWnitted
through
the
applied
rear
clu
tch
to
the
internal
gear
of
the
front
gear
set
The
c1o
kwise
rotation
o
f
the
front
inter
naI
gear
causes
the
front
planet
gears
to
rotate
clockwise
driving
the
com
pound
sun
gear
counterclockwise
The
front
planetary
carrier
is
splined
to
the
output
shaft
This
cau
the
planet
gears
to
drive
the
sun
gear
instead
of
walking
around
the
sun
gear
This
counterclockwise
rotation
of
the
sun
gear
causes
the
rear
planet
gears
to
rotate
clockwise
With
the
one
way
clutch
holding
the
rear
planet
carrier
the
rear
planetary
gears
turn
the
rear
internal
gear
and
output
shaft
clock
wise
in
a
reduction
ratio
of
approxi
mately
2
46
to
L
Fluid
flow
Manual
Valve
2
3
Automatic
Transmission
Fiont
gear
set
Rear
gear
set
Input
t1uOllsh
rear
clutch
Output
shaft
Held
by
on
way
clutch
Input
from
front
gear
set
Output
to
real
gear
set
AT330
1
J
ld
AT081
Front
clutch
Reu
clutch
Low
and
revcrx
brake
Brake
band
servo
Onto
way
clutch
OFF
ON
OFF
OFF
HOLDING
Fig
AT
12
MochanicaIOp
rationduri
DJ
Ra
Governor
Valve
Pressure
Modifier
Valve
15
2nd
3rd
Shift
Valve
lst
2nd
Shift
Valve
2nd
3rd
Timing
Valve
1st
2nd
Shift
Valve
j
Rear
Clutch
I
Second
Lock
Valve
Second
Lock
Valve
LOrifice
Check
Valve
2nd
3rd
Shift
Valve
AT12
Page 265 of 548
D
ran
Low
r
Oil
pump
l
t
Torque
convlrter
pr
ur
rlgula
Tor
yalvl
t
t
1
L
Line
pr
ur
l
Governor
preslur
Automatic
Transmission
Fr
on1
clutch
Rear
cl
ulch
t
l
Torque
conyert
pressure
Throttle
pr
iur
Brake
ba
n
d
o
h
Band
I
b
rvo
I
Low
0
nd
reven
brQke
t
l
Thralll
pre
ur
t
1V
Governor
pre
sur
AT448
Fig
AT
J3
Oil
Pr
ure
Circuit
Diagrom
D
rang
Low
gear
AT13
Page 266 of 548
D2
RA
NGE
2ND
GEAR
Power
flow
In
02
range
the
brake
band
is
applied
to
hold
the
connecting
shell
and
sun
gear
stationary
Engine
torque
through
the
applied
rear
clutch
is
delivered
to
t
he
int
D
1l
1
gear
of
the
front
gear
set
in
a
clockwise
rotation
Clockwise
rotation
of
the
internal
gear
causes
the
planet
gears
to
walk
around
the
stationary
sun
gear
in
a
clockwise
direction
This
causes
the
output
shaft
which
is
splined
to
the
front
planet
carrier
to
turn
ina
clock
wise
direction
with
a
reduction
ratio
of
about
I
46
to
I
Fluid
flow
As
car
speed
and
governor
pressure
increase
the
governor
pressure
acting
on
the
end
of
the
1
2
shift
valve
Manual
Valve
I
Automatic
Tra
l
mission
Front
Bear
set
Rear
gear
set
Input
throuah
rear
clutch
AT331
1f
j
cW
oo
w
I
ATD79
Front
Clutch
Rearc1utch
Low
and
reverse
brake
Broke
band
One
way
clutch
OFF
ON
OFF
ON
OFF
AT447
F
S
AT
14
MechanicalOperation
during
DJ
Range
overcomes
the
force
of
the
1
2
shift
valve
spring
and
line
pressure
This
allows
the
1
2
shift
valve
to
move
to
the
upshift
position
which
directs
line
pressure
through
the
2nd
lock
valve
and
on
to
the
brake
band
Governor
Valve
15
Pressure
Modifier
Valve
2nd
3rd
Timing
Valve
2nd
3rd
Shift
Valve
1st
2nd
Shift
Valve
econd
Lock
Valve
9
Band
Servo
I
Apply
Side
1st
2nd
Shift
Valve
8
l
Rear
CIutclt
I
Second
Lock
Valve
2
3
Second
Lock
Valve
L
Orifice
Check
Valve
2nd
3rd
Shift
Valve
AT
14
Page 267 of 548
0
ren
e
2nd
gear
1
Oil
pump
l
t
ra
d
l
t
Tor
q
UI
convlrt
r
Prlssure
rlQulotor
valvl
Automatic
Transmission
Front
clutch
tt1t
P
RN021
Rear
clutch
Brake
band
LOllii
ond
rlverse
brake
Govern
or
preslure
t
Line
pressure
Governor
pre
ur
j
iiiiB
Torque
canverter
prollure
Throttle
pre
ur
AT448
Fir
AT
15
Oil
Pr
re
Circuit
D
m
D
rang
2nd
g
ar
AT15
Page 269 of 548
D3
ran
3rd
g
ar
Oi
I
pump
1
t
Torque
J
C
onYlrt
r
I
i
t
t
Pressure
reQula
or
Ya
lye
L
i
ns
pressure
Goyernor
pressure
Automatic
Transmission
Front
clurch
Rlar
clutch
Brake
bond
Low
and
rever
brake
0
thBond
L
B
so
J
1
1
1
lt
r
T
tr
Throttle
pressure
t
t
I
@
t
Governor
pr
au
r
Torque
canYlr
er
pr
ssure
rIA
Throttle
pressure
AT449
Fill
AT
17
Oil
Pro
ure
Circuit
Diagram
D3
range
3rd
gear
AT
17
Page 276 of 548
X
F
1
2
dll
U
Sflift
lllvI
21
I
S
nd
lock
6
Ir
II
P
UX
6
I
Mo
ol
f
L
t
u
uu
u
u
I
f5
LI
P
OI
I
Go
o
fo
d
P
I
ren
e
2nd
eer
Torqul
con
rter
Oil
pump
Oil
tool
RIAr
Ivbri
cor
ion
D
Orain
fa
hi
Front
lubrici
lti
0
0
0
1
I
tU
x
j
Pr
l
UQU
010r
Yol
u
1
Automatic
Transmission
Front
lulch
Riot
x
l
N
r
N
N
I
I
i
l
I
18
16
ahl
J
@
Vacuum
Huottl
Vol
if
J
II
Throttl
drain
yol
l
II
@2ft
3rd
Shiff
101
1
iii
1J
g
2nd
3rd
timino
101
11
8
Goy
rnor
prlUUAI
Torque
Cony
tar
pr
r
Th
toni
pt
ure
Slcondor
governor
vol
1
Primo
00
vlrnor
va
AT461
Fig
AT
21
Oil
Pr
Circuit
Dwgrom
12
ro
2nd
ear
AT
24