1979 DATSUN 210 Service Manual

Note
When
tho
vaCUUm
hose

is
dis

connected

plug
it

up
or

engine
will

stumble

EC
47A

FiJ
Fig
EC
49

Disconnecting
Vacuum

Hose

from
C
A

C
Valve

5

Connect

hand
operated
vacuum

pump
in

place
and

manipulate
it
in

order

to

apply
a

pressure
of
2oo
to

250

mmHg
7
87

to
9
84

inHg

to

C
A
C

valve
Increase

engine
speed

to
3
000

rpm
and
confIrm
that

no
air

leaks
from
C

J
C
valve

Fig
EC

50

Checking
C
A
C

Valve

1

6
With
the
above

condition
discon

nect
air
hose
at
check
valve
and

plug
it

up
At
this

point
confirm

the
air

leaks

from

C
A

C
valve

ECl48A

Fig
EC

51

Checking
C
A
C
Volve
2
Emission

Control

System

7
If

teshesults

satisfy
3
4
5

and
6

the
C
A
C
valve

is

properly
function

ing

AIR
INDUCTION

SYSTEM
A
I
S

DESCRIPTION

The
air

induction

system
A
1
s
is

adopted
on
the
FU
model
and
Canada

models
and
is

designed
to
send
see

ondary
air
to
the

exhaust
tube
utiliz

ing
a
vacuum
caused

by
exhaust

pulsa

tion
in
the

exhaust
tube

Air
inductIon
valve

A
reed

valve

type
check
valve
is

installed
in

the
air

cleaner
When
the

exhaust

pressure
is
below

atmospheric

pressure

negative
pressure

secondary

air

is
sent
to
the
exhaust
manifold

When
the
exhaust

pressure
is

above

atmospheric
pressure
the

reed
valve

prevents

secondary
air

from

being
sent

back
to
the
air
cleaner

EC
t8
The

exhaust

pressure
in

the
exhaust

tube

usually
pulsates
in

response
to

the

opening
and

closing
of

the
exhaust

valve
and

it
decreases

below
atmos

pheric
pressure
periodically

If
a

secondary
air
intake
is

opened

to
the

atmosphere
under

vacuum
con

ditions

secondary
air

can
be

drawn

into

the
exhaust
tube
in

proportion
to

the
vacuum

Therefore
the
air
induction

system

A
I
s
reduces
CO

and
HC
emissions

in

exhaust

gases

operatiug
the
same
as

the
air

injection

system
A
I
s
The

system
cpnsistsof
an
air

in

tJctio

valve

a
filter
an

A
B
valve

and
hoses

fl

V

t

5

1

Air

ind9ction
valve

2
Air

c
eancr

3
Carburetor

4

Exhaust
manifold

5

Anti
obRcldlre
valve

EC919

Fig
EC
52

Ai
Induction

SYltem

1

Reed
valvo

2

Stopper

EC920

Fig
EC

53
Air
Induction

Val

Air
Induction
v
lve
filter

The
air
induction
valve
filter
is

installed
at
the
dust
side
of
the
air

cleaner
It

purifies
secondary
air

to
be

sent
to
the

exhaust
tube
The
fIlter

element
should
be

replaced
periodical

ly
in
accordance
with
the
Maintenance

Schedule

EC921

Fig
EC
54
Air
Induction
Valve

Filter

Antl
beckflre
v
lve
A
B
v
lve

Tltis
valve
is

controlled

by
intake

manifold
vacuum
to

prevent
backfire

in
the

exhaust
system
at
the
initial

period
of
deceleration

At
this

period
the
mixture
in

the

intake
manifold
becomes
too
rich
to

ignite
and
burn
in

the
combustion

chamber
and
burns

easily
in
the
ex

haust

system
with

injected
air
in
the

exhaust
manifold

The
anti

backfire
valve

provides
air

to
the
intake

manifold
to
make
the

air
fuel
mixture
leaner
and

prevents

backfire

If

the
valve
does
not
work

properly

unburned
ntixture
will
be

emitted

from

the
combustion
chambers
and

burns
with
the
aid
of

high
temperature

and

injected
air
which

causes
backfrre

To
intake

manifold

vacuum

To
intake

manifold

From
air

cleaner

EC069

Fig
EC
55
Anti

backfire
Value
Emission
Control

System

Air
Induction
Into
exhaust

port

The

secondary
air
fed
from
the
air

induction
valve

goes
through
the
check

valve
to
the
air

gallery
in

the

cylinder

head
It
is
then

distributed
to

each

exhaust

port
and

injected
near
the

exhaust
valve

I
Air

gallery

2
Exhaust

port

3
Exhaust
manifold

EC316

Fig
EC
56
Sectional
View

of

Exhaust
Port

REMOVAL
AND

INSTALLATION

Air
Induction
valve
and
filter

Remove
the
screws

securing
the

valve
and
filter
to
the
air

cleaner
body

The
air
induction
valve
and
valve
filter

can
then
be
taken

out

easily
Installa

tion
is
in
the
reverse

sequence
of

removal

EC922

Fig
EC
57

Removing
Air
Induction

Valve
and
Filter

EC
19
Air
Induction

pipe

Loosen
out
a

nut
securing
the

pipe

to

the

engine
cylinder
head
At
the

same
time
remove
the
screws

securing

the
bracket
and
rubber
hose

clamp

The
air
induction

pipe
can
then
be

taken
out
Installation
is
in
the
reverse

sequence
of
removal

Fig
EC
58

A
B
valve

The
A
B
valve
is
located
at
the

rear

side
of
the
air
cleaner
Remove

the
air

hoses
and
vacuum
tube

The
A
B
valve

can
then
be

taken

out
Installation
is
in
the

reverse
se

quence
of
removal

EC152A

Fig
EC
59

Removing
A
B
Valve

INSPECTION

Preliminary
Inspection

Check
hose
for
looseness

flatting

damage
or

faulty
connections
and

each

part
for

proper
installation
If

necessary

replace

Air
Induction
valve
and
filter

I
Disconnect
air
induction
hose
at

air
induction

pipe
side
Suck
or
blow

hose
to
make
sure
that
air

flows

only

on
the
air

induction

pipe
side

EC924

Fig
EC

60
Checking
Air
Induction

Valve

2

Check
air
induction
valve
reed

valve
for

binding
or

damage
At
the

same
time
check
filter
for

damage
or

plugging
If

necessary
replace
Filter

should
be

replaced
periodically
in
ac

cordance
with
Maintenance
Schedule
Emission

Control

System

1
Air
induction
valve
filter

2

Air
induction
valve

EC925

Fig
EC
6I
Checking
Air
Induction

Valve
and
Filter

Anti
backfire
valve
A
B
alve

I
Warm

up
engine
thoroughly

2
Disconnect
hose
from
air
cleaner

EC
20
and

place
aflriger
near
tneoutlet

3

Run

engine
at
about
3

000

rpm

under
no
load
then

quickly
return
it

to
idling
If

you
feel
a

pull
or

suction

force

on

your
finger
the
anti
J
ackfire

valve
is

functioning

normally
If
no

suction
is
felt

replace
the
anti
backfire

valve

eC76S

Fig
EC
62

Checking
Anti
bock
ire

Valve

Emission
Control

System

EXHAUST
GAS

RECIRCULATION

E
G
R
CONTROL

SYSTEM

DESCRIPTION
to
lower
the

spark
flame

temperature

during
combustion
This
results

in
a

reduction
of
the

nitrogen
oxide

NOx

content
in
the
exhaust

gas

When

the
E

G
R
control
valve

is

open
some
of
the
exhaust

gas
is
led
from
the

exhaust
manifold
to
the

E
G

R

chamber

through
the
E

G
R

passage
The

exhaust

gas
is

then
con

trolled
in

quantity
by
the
E

G
R

valve
and

is
introduced
into
the
intake

manifold

In

the
exhaust

gas
recirculation

system
a

part
of
the

exhaust

gas
is

returned
to

the
combustion

chamber

U
S
A

models

c

r

i

From
carburetor

EC309A

1
E
G
R
thermal
vacuum
valve

2
E

G
R
control

valve

3
Carburetor

4
E
G
R

passage

5
Intake
manifold
6
Exhaust
manifold

7

E
G
R

tube

8
Orifice

9
B
P
T
tube

10

B
P
T

valve

Canada
models

CD

o

1

Thermal
vacuum

valve

2
E
C
R
control
valve

3
Carburetor

4

E
C
R

passage
5
Intake
manifold

6
Exhaust
manifold

7

E
G
R

tube
Thermal
vacuum

valve

3
port
type
T
V
V

Thermal
vacuum
valve

2
port
type
T
V
V
for
FU
model
E
G
R
tube

E

G
R

control
valve

4

Thermal
vacuum
valve

2

port
type
T
V
v

E
G
R
tube

EC155A

Fig
EC
63
E
G

R

System

EC
21

Emission
Control

System

ATloN

The

operation
of
the
E

G
R

system
is

as
follows

U

S
A

models

Except
FU
model

Thermal

Water

temperature
Oc
OF

vacuum
valve
B
P
T
valve

Exhaust

pressure
mmH20
inH20
E
G
R

system

Below

SO
to

63

I22
to
145
Open
Exhaust

pressure

Below
21

to
33
0
82
to
1
30
Open

Not

actuated

Above

21
to

33
0
82
to

1
30
Closed

Exhaust

pressure

Open
Not
actuated

Aliove

Closed
Below
21
to
33

0
82
to
1
30

SO
to

63

I
22

to
145

Above
21
to
33

0
82

to
130
Closed

Actuated

FU
model

Water

temperature
Oc
F
Thermal
B

P
T
valve

E
G
R

system

vacuum
valve

Exhaust

pressure

mmH20
inH2O

Below
Below
21
to
33
0
82
to

1
30

Open

Closed
Not
actuated

40
to
63
104
to
145

Above
2
to

33
0
82
to
1
30
Closed

Above
Below
21

to
33

0
82
to
1
30

Open
Not
actuated

40
to
63
104
to
145
Open

Above
21
to

33
0
82
to
1
30
Closed
Actuated

Canada
models

Water

temperature
Oc
OF
Thermal

vacuum
valve
E

G
R

system

Below
40

to
63

I04
to
145

Closed

Not
actuated

Above
40
to
63

I04
to
145

Open
Actuated

E
G
R
control
valve

The
E

G
R
control

valve

controls

the

quantity
of
exhaust

gas
to
be
led

to
the
intake

manifold

through
vertical

movement
of
the

taper
valve
con

nected
to
the

diaphragm
to
which
vacuum
is

applied
in

response
to
the

opening
of

the
carburetor
throttle

valve

E
G
R

control
valve
construction

and

type
vary
with

transmission

type
and
car
destination
For
identification

purposes
the

part
number

is

stamped

on
the
recessed

portion
at
the

top
of

the
valve

EC22

1l

I

I

1J

1

Diaphragm
spring

2

Diapliragm

3
Valve
shaft

4
Valve

5
ValVe

seat

6
Valve
chamber

EC231

Fig
EC
64
E
G
R
Control
Value

Thermal
vacuum
valve

2

port

type

FU
and
Canada
models

The
2

port

type
thermal
vacuum

valve
is
mounted
on
the

engine

thermostat

housing
It

detects

engine

coolant

temperature
by
means
of
a

built
in

bi
metal
and

opens
or
closes

the
vacuum

passage
in
the

thermal

vacuum
valve

When
the
vacuum

passage
is

open

the

carburetor
vacuum

signal
is

applied

to
the

diaphragm
of
the
E
G
R
con

trol

valve
to
actuate
the

taper
valve

connected
to
the

diaphragm

1

Spring

2

Bi
metal

3
O

ring

EC232

Fig
EC
65
Thermal
Vacuum
Valve

2

port
type
Emission
Control

System

Thermal
vacuum
valve

3

port
type

U
S
A
models

except

FU

model

The
3

port
type
thermal

vacuum

valve
is
located

on
the
rear

end
of
the

cylinder
head

It

defects

engine
coolant

tempera

ture

by
means
of
wax

expansion
and

opens
or
closes
the
air

passage
from

the
air

cleaner

When

the
air

passage
is
closed
the

carburetor
vacuum
signal
is

applied
to

the

diaphragm
of
the
E
G
R

control

valve
to
actuate
the

taper
valve
con

nected
to
the

diaphragm
This
valve
is

also
co
used
as
a

component
for
the

Spark
Timing
Control

System

JiI2
To
air
cleaner

From
B
P
T

valve

From
distributor

EC156A

Fig
EC
66
Thermal
Vacuum
Valve

3

port
type

B
P
T
valve

The
B
P

T
valve
monitors
exhaust

pressure
to
activate
the

diaphragm

controlling
intake

manifold
vacuum

applied
to
the
E
G
R

control
vaNe
In

other
words
the

amount
of
recirculat

ed
exhaust

gas
vari

s
with
the

position

of
the
E
G
R

valve

regulated
by
the

operating
condition
of
the

engine

EC
23
To
E

G
R

control
valve
Vacuum
nal
Curce

Air
bleed
1

Exhaust

pressure

EC310A

Fig
EC
67
B
P
T
Value

REMOVAL
AND

INSTALLATION

E
G
R
control
valve

I
Disconnect

vacuum
hose
and
re

move
nuts

securing
E
G
R

control

valve
to
E

G
R

passage
The
E

G
R

control
valve

can
then
be
taken
out

Fig
EC

68

Remouing
E
G
R

Control
Valve

CAUTION

Pay
attention

not
to

give
damage
to

packing
of
E
G
R

control
valve

2

Installation
is
in

the
reverse
se

quence
of
removal

Note
In

installing
new
E
G
R

control

valve
confirm
that

the
model

num

ber
and

identification
marks
at

the

top
of
valve
are

as
follows

E
G
R
passage
arid
taibe

I

E
G
R

tube
can
be
removed

by

loosening

securing
nuts

2

Disconnect

blow

by
gas
hose
and

remove

securing
bolts
and

nuts
E

G
R

passage
can

then
be
taken

out

3

Installation
is
in
the

reverse
se

quence
of
removal

EC158A

Fig
EC
S9

Removing
E
G
R

Passage

Note

New

gasket
should

be
used
in

installing
E

G
R

passage

Thermal
vacuum
valve

The
thermal

vacuum
valve
is

made

of

plastic

Consequently
pay
attention

not
to

give
damage
to
it

On
U
s
A

models

except
for

the

FU

model
the
3

port
type
thermal

vacuum

valve
is
located
on
the

rear

end

of
the

cylinder
head

On
Canada
and

FU
mode
the

valve
is

located
on

the
front
end
of
the

cylinder
head
Emission

Corltr
ol

System

I
Drain

engine
coolant
about
one

liter

I
US

qt
Imp
qt

2

Remove
manifold
nut

securing

heat

shield

plate

I
I

LIkat
shield

plate

EC170A

Fig
EC

70

Removing
Heat
Shield

Plate

3
Disconnect
two

vacuum
hoses

and
unscrew
the
thermal
vacuum

valve
The
valve

can
then
be
taken
out

4

Installation
is
in
the

reverse
se

quence
of
removal

Note

a

Be
sure
to

apply
sealer
to
threads
of

the
valve

prior
to

installing
new

wive

b
When

installing
new

thermal
vacu

um
wive
make

sure
it
is

black

t
J

Tightening
torque

Thermal

vacuum
valve

Less
than

2
2

kg
m
16
ft
b

Manifold
nut

1
5
to

2
0

kg
m

11

to
14
ft
b

EC
24
2

port

type

3
port

type

Fig
EC
71

Removing
Thermal

Vacuum
Valve

B
P
T
valve

I

Remove

vacuum
tube
on
the

B
P
T

valve

2

Remove

screws

securing
B
P
T

valve
to

bracket

3
Disconnect
back

pressure
tube

from

B
P
T
valve

The
B
P
T

valve
can
then
be

taken

out

EC770

Fig
EC

72

Removing
B
P

T
S

curing

Screws

4

Installation

is
in

the
reverse
se

quence
of

removal

Note
In

replacing
the
B
P
T

valve

with

new
one
h
that
the

type
number
on

new

part
is
the

same
85
that
on
former

one

INSPECTION

Entire

system

I

Make
a

thorough
vjsual
check
of

E

G
R

control

system
If

necessary

wipe
away
oil
to
facilitate

inspection

If

any
hoses

are
cracked
or

broken

replace

2

With

engine
stopped
inspect

E

G
R

control
valve
for

any
indication

of

binding
or

sticking
by

moving
dia

phragm
of
control
valve

upwards
with

a

finger

3
With

engine
running
inspect

E

G
R

control
valve
and
thermal
vacu

um
valve
for
normal

operation

1
When

engine
coolant

tempera

tun
is
low

Make
sure
that
E

G
R

control
valve

does

not

operate
when

engine
speed
is

increased
from

idling
to
3
000
to

3

500

rpm

Place
a

finger
on
the

diaphragm
of

E
G
R

control
valve
to
check
for
valve

operation

EC773

Fig
EC
73

Checking
E
G
R
Control

2

When

engine
coolant

tempera

tureishigh
Emission
Control

System

Make

sure
that
E
G

R
control
valve

operates
when

engine
speed
is
in

creased
from

idling
to
3
000
to
3
500

rpm
Place

fingers
on
the

diaphragm
of

E

G
R
control
valve
to
check
for
valve

operation

If
E
G

R
control
valve
does

not

operate
check
as
follows

Disconnect
one
end
E

G
R

control

valve
side

of
vacuum
hose
connect

ing
ihermal

vacuum
valve
to

E
G
R

control
valve

Increase

engine
speed
from

idling
to

3
000
to
3

500

rpm

Make
sure
that

thermal
vacuum

valve
is

open
2

port
type
or

closed
3

port
type
and

that
car

buretor
vacuum
is

present
at
the

end
E
G
R

control
valve
side
of

vacuum
hose

If

vacuum
is

weak
or

not

present
at

all

replace
thermal

vacuum
valve
If

vacuum
is

present
check
E
G
R

control
valve
or
B
P

T
valve

If

any
difficulty
is
encountered
in

judging
the
condition
of

any
com

ponent
during
above

inspection
check

the

questionable

component
in

dependently
as
follows

U

S
A

models

Ie

EC160A

Canada
models

ET429

Fig
EC
74

Checking
Vacuum

of

E
G
R
Control
Valve

EC
25
E
G
R
control
valve

Dismount
E
G

R
control
valve

from

engine

I

Apply
vacuum
to
E
G
R
control

valve

referring
to
the

following
figure

If
the
valve
moves
to
full

position
it
is

normal

E

G
R

control
valve
will
remain

open
for
more
than

30
seconds
after

vacuum
has
cut
off

5t
orr

rl

1

1

Fig
EC
75
EC129A

Checking
E
G
R
Control

Valve

2

Visually
check
E
G
R
control

wive
for

damage
wrinkle

or
deforma

tion

3

Clean
the

seating
surface
of

E
G
R
control
valve
with
a

brush
and

compressed
air
and

remove

foreign

matter
from
around
the
valve
and

port

Fig
EC

76

Cleoning
E
G
R
Control

Valve

Thermal
vacuum
valve

3

port
type

Remove
thermal
vacuum
valve
from

engine
Inhale
air

from

port
ofE
G
R

system
and
check
to
be
sure
that

thermal
vacuum
valve

opens
or
closes

in

response
to
its

temperature

Thermal

vacuum
valve

dosing

temperature

Above
50

to
630
C

122
to
1450
F