1979 DATSUN 210 check engine

EF053A

Fig
EF

50

Removing
JWrneu

of

Solenoid
valve

2

Connect
rubber
hose

between

vacuum

gauge
and
intake
manifold

Note
A

quick
response
type
boost

gauge
such

as
Bourdon
s

type
is

recommended
a

mercury
type

manometer
should
not
be

used

3
Warm

up
engine
until
it

reaches

operating

temperature
Then

confirm

that

engine
idling

speed
is

specified

valve

Engine

idling
speed

Manual

transmission

700

rpm
Engine
Fuel

Automatic
transmission

in
0

position

650rpm

Note

On
automatic

transmission

models
never

race

engine
when

gearshift
lever

is
in
0

position

4
Run

engine
under
no

load
In

crease

engine
speed
to
3

000

to
3
500

rpm
then

quickly
close
throttle
valve

S
At
the
time
manifold

vacuum

pressure
increases

abruptly
to

600

rnmHg
23
6

inHg
or
above
and

then

gradually
decreases
to
the
level

set
at

idling

a

Maximum

negative
pressure

b

Operating
pressure

c

Idling
pressure

Nega
ive

pressure

EC502

Time

Fig
EF

52
Characteristic
Curve

of

T
O
C
S

6
Check
that
the
T

O
C
s

operating

pressure
is

within
the

specified
pres

sure

Specified

pressure
0
m

sea
level

end
760

mmHg
30

inHgl
atmOs

pheric
pressure

Non
Califomia

models

520
20

mmHg

20
47
0
79

inHg

California
models

560
20

mmHg

22
05

9
79

inHgl

7

I

If
it
is
lower

than
the

specified

level

turn
the

adjusting
screw
or

nut

in
the

following
direction

until
correct

adjustment
is

made

Adjusting
nut

Clockwise

2
If
it
is

higher
than
the

specified

levei
turn
the

adjusting
screw
or

nut

in
the

following
direction
until
correct

adjustment
is

made

EF
20
Adjusting
nut

Counterclockwise

Note

When

adjusting
T

O
C
S
turn

adjusting
nut
in
or
out
with
lock

spring
in

place
Always
set
lock

spring
properly
to

prevent
changes

in

set

pressure

Vo

1

Adjusting
nut

2
Lock

spring

n

EC802

EF055A

Fig
EF
53

Adjusting
Ope
llting

Pre
3ure

Note
The

operating

pressure
varies
in

proportion
to
altitude

a
When

atmospheric

pressure
is

known

operating
pressure
will
be

found

by
tracing
the

arrow
line

A
When

altitude
is

known

op

erating

pressure
will
be

found

by

tracing
the

arrow
line

B

b

When

checking
T

O

C
S

operating

pressure
note

atmospheric
pressure

and
above
sea

level
in
which

check

is

to
be
made
and
determine
set

pressure
by
the

information
fur

nished

For

example
if
above
sea
level
is

1

000
m
3
280
ft

operating
pres

sure
will
then
be
475

mmHg

18
7

inHg
on
non

California

models
or
495

mmHg
19
5

inHg
on
California
models

In
other
words
T

O
C
S

operates

at
475

mmHg
18
7

inHg
or

490

mmHg
19
3

inHg

8
Race

engine
and

check
for

adjust

ment

9
If

engine
speed
will

not

drop
to

idling
speed
when

checking
throttle

opener
operating

pressure
proceed
as

follows

I
Turn

adjusting
screw
counter

clockwise

so
that
throttle

opener
oper

ating
pressure
is
on

high
vacuum
side
Engine
Fuel

25

mmHg
0

98

inHg
away
from
the

specified
value

2

Turn

adjusting
screw
l
O
of
a
turn

clockwise

so
that
throttle

opener
oper

ating
pressure
drops
by
25

mmHg

0
98

inHg

10
If
throttle

opener
operating

pressure
cannot
be
observed

clearly

even
in

step
9

proceed
as
follows

I
Turn

adjusting
screw
counter

clockwise

so
that
tluottle

opener

oper

ating
pressure
is
on

high
vacuum
side

50

mmHg
1
97

inHg
away
from

mid

point
of
the

specified
range

2
Turn

adjusting
screw
l
of
a
turn

clockwise

Note

The
throttle

opener
operating

pressure
should
be

correctly
set

within
the

specified
range
after
the

above

adju
stments
even
if
the
en

gine
speed
cannot
be
decreased
to

idling

inHg
mmHg

30

750

29

28

24

A

600

700

23
27

560

26
22

550

650

21
25

0

0
20
24

500

600
0

0

19

23

c

o

c

22

ii
18
0

0
450

550
E

c

0

17
2

16
20

400

500

15
B

Non
California
model

350
14

California
model

13

300

5

000
6

000
1ft

0
1
000
2
000
3
001
4
000

0
0
5
1
5
2
km

Altitude

EF056A

Fig
EF
54

Clumges
in

Operating
Pressure
Versus

Changes
in

Atmospheric

Pressure

EF
21
SERVO
DIAPHRAGM

STROKE

I
Connect

engine
tachometer

2
Warm

up
engine
until
it

reaches

operating
temperature

3
Disconnect
rubber
hose
between

servo

diaphragm
and

vacuum
control

valve

Then

connect
rubber

hose
to
in

take
manifold

Servo

diaphragm

Rubber
hose

T

O
C
S

solenoid
valve

T

O
C
S
control
valve

EF250

EF057A

Fig
EF
55

Connecting
Rubber
Hose

to

Intake

Manifold

4
Servo

diaphragm
is

functioning

properly
if

engine
speed
comes
into

the

specified

range

Specified
engine
speed

1
650

to

1
850
rpm

except

Californial

1

900
to
2

100

rpm

for
California

5
If

necessary
adjust
engine
speed

until
it
is
in
the

specified
range
using

servo
diaphragm

adjusting
screw

When

engine

speed
is

lower
than

the

prescribed
range

Turn

adjusting
screw

clockwise

When

engine
speed
is

higher
than

the

prescribed
range

Turn

adjusting
screw

counterclockwise

1

Servo

diaphragm
4

Stopper

2
Bracket
5
Link

3
Lock
nut
6
Carburetor

EF732

Fig
EF
56

Adjusting
Seroo

Diaphragm

Adjwting
Screw

FUEL

SHUT
OFF

SYSTEM

Precautions

a

Before

checking
make
sure

engine

is

warmed

up
and
choke
wive
is

fully
open

b

On
air
conditioner

equipped
mod

els
turn
off

air
conditioner
switch

in

steps
I

through
12

c

Keep
clutch

pedal
held
down
with

your
foot
while

depressing
accele

g

f
J

1
Engine
Fuel

rator

pedllI
when
shift
leVer
ISm

any
position
other
than

neutral

Otherwise
car
will

surge
forward

abruptly

Note
Do

not
attach
test
leads
of
a

circuit
tester
to
terminals
other

than
those

designated

Run

engine
at

idling

speed

2
Disconnect

anti
dieseling
solenoid

valve
connector
and
make

sure
that

engine

stops
If

not

replace
anti

dieseling
solenoid
valve

assembly

EF856

Fig
EF

57

Checking
Function

of

Anti
die

eling
Solenoid
Valve

31
A

t

CID

@

V

II
l

To

distributor

T
n

l1on
coon
o

1

Ignition
switch

2
Fuse

3

Anti
dieseling
solenoid

4

Neu
tral

detecting
switch
5
Throttle
valve
swltch

6

Engine
revolution
switch

7

Transistor

ignition
unit

8
Function
test
connector

Fig
EF
58

Checking
Fuel
Shut
off

System
Operation
with
Function

Test
Connector
EF436A

EF
22
3
Conilect
anti

ieselingsolenoid

valve
connector

4
Restart

engine

5
Connect

circuit
tester

as
shown
in

Fig
EF
S8

6

Depress
clutch

pedal
and

shift

gears
into
5th

position

7

Depressing
clutch

pedal
increase

engine
speed
to

about
3

000

rpm
by

depressing
accelerator

pedal
Then

quickly
close
throttle
wIve

by
re

leasing
accelerator

pedal

8
At
this
time
check

for

presence

of

voltage
across
A

and
B

I
If

voltmeter

reading
i
ero
dur

ing
acceleration
and
is
12V

during

deceleration
fuel
shut
off

system
is

functioning

2
If

voltmeter

reading
is

zero
or

l2V
in

both

engine
operations
fuel

shut
off

system
is

malfunctioning

In

any
case
continue
with
the

following
items

9

Shift
lever
to
neutral

then
in

crease

engine
speed
and

quickly
close

throttle
valve

If

voltmeter

reading
is

zero
in
both

engine
operations
and
results
of
test

i
tern

8
are
correct
neutral

detecting

switch
is

functioning
properly
If
not

check
neutral

detecting
switch
harness

and
connections

Replace
if

necessary

10
Turn

off

ignition
switch

II

Disconnect
throttle
valve
switch

connector
and
connect

circuit
tester

to
throttle
valve
switch
connector

12

Run

engine
under

no
load
In

crease

engine

speed
slowly
and
make

sure

engine
speed
is
within
the

speci

fied

range
when
throttle
valve
switch
is

turned
on

Then

decrease

engine
speed
slowly

and
make
sure

engine
speed
is
within

the

specified
range
when
throttle
valve

switch
is
turned

off

If
not

adjust
throttle
valve

switch

13
In
air

conditioner

equipped

models

proceed
as
follows

I
Check
F
l
C
D

rpm
and
correct

if

necessary

2
With

air
conditioner
in
ON

F
l
C
D
is
actuated
increase

engine

speed
slowly
then
decrease
it
And

make

sure
throttle
valve

operates

Click
sOund
is
heard
or

continuity

turns
to
OFF
when

engine
speed

decreases
to

idling

If
not

adjust
throttle
valve
switch

Fig
EF

59

Adjusting
Throttle

Valve
Switch
Eng
ine
Fuel

If
throttle
valve
switch
cannot
be

adjusted
to

specification
replace

Engine
operation
Throttle
valve
switch

continuity
Engine
speed

rpm

When

engine
speed

increases
OFF
ON
1
150

t200

When

engine
speed

decreases
ON

OFF
I
000
t
200

Inspecting
engine
revolution

switch

Note
Before

checking
the

engine

revolution
switch

make
sure

the

functions
of
other

components
are

correct
in
accordance

with
the

items

described
above

Disconnect
throttle
valve

switch

connector
2
Connect
circuit
tester

3
Run

engine
at

idling
speed

4

Depress
clutch

pedal
and
shift

gear
into
5th

position

5

Depressing
clutch

pedal
increase

engine
speed
slowly
Make

sure

engine

speed
is
within
the

specified
range

when
voltmeter

goes
from
OV
to
l2V

Then
decrease

engine

speed
slowly

and
make

sure

engine
speed
is
within

the

specified
range
when
voltmeter

goes
from
12V

to
OV

EF
23
MAJOR
SERVICE

OPERATION

The

perfectly
adjusted
carburetor

deliver
the

proper
fuel
and
air
ratios

at
aD

speeds
for
the

particular
engine

for
which
it

was

designed
By
com

pletely
disassembling
at
re
ular
inter

vals
which
will
allow

cleaning
of
all

parts
and

passages
the
carburetor
can

be
maintained
in
its

original
condition

and
will

continue
to
deliver
the

proper

ratios

To
maintain
accurate
carburetion

of

passages
and

discharge
holes
ex

treme
care
must
be
taken
in

cleaning

Use

only
carburetor
solvent
and

compressed
air

to
clean
all

passages

and

discharge
holes
Never

use
wire

or

other

pointed
instrument
to
clean
or

carburetor
calibration
will
be
affected

REMOVAL

Remove
carburetor
from

engine

taking
sufficient

care
to
the

following

Precautions

a
When

disconnecting
fuel
lines
do

not

spill
fuel
from
fuel

pipe

b
When

removing
carburetor

do
not

drop

any
nut

or
bolt
into

intake

manifold

c
Be

careful
not
to
bend
or
scr
tch

any

part

d
Link

system
of
carburetor
differ

between
models
for
U
S
A

and

Canada
For
details
see

Figure
EF

60
which
is
based
on
Canadian

models

CLEANING
AND
INSPECTION

Dirt

gum
water
or
carbon
con

tamination
in
or
on
exterior

moving

parts
of
a
carburetor
are
often

respon

sible
for

unsatisfactory
performance

For
this

reason
efficient
carhuretion

depends
upon
careful
cleaning
and

inspection
while

servicing

Blow
all

passages
and

castings

with

compressed
air
and
blow
off
all

parts
until

dry

Note
Do
not

pass
drills
or
wires

through
calibrated

jets
or

passages

as
this

may

enlarge
orifice
and

seriously
affect
carburetor
calibra

tion

2
Check
all

parts
for
wear
If
wear

is
noted

damaged
parts
must
be
re

placed
Note

especially
the

following

I
Check
float
needle
and
seat
for

wear
If
wear
is

noted
assembly
must

be

replaced

2
Check
throttle
and
choke
shaft

bores
in
throttle
chamber
and
choke

chamber
for
wear
or
out
of
roundness

3

Inspect
idle

adjusting
needle
for

hurrs
or

ridges
Such
a
condition
re

quires
replacement
Engine
Fuel

3

Inspect
gaskets
to
see
if

they

appear
hard
or

brittle
or
if

edges
are

torn
or

distorted
If

any
such

condi

tion
is
noted

they
must
be

replaced

4

Check

filter
screen

for
dirt
or
lint

Clean

and
if
screen
is

distorted
or

remains

plugged
replace

5

Check

linkage
for

operating

condition

6

Inspect
operation
of

accelerating

pump
Pour
fuel
into
float
chamber

and
make
throttle
lever

operate
Check

condition
of
fuel

injection
from
the

accelerating
nome

7
Push

connecting
rod
of
dia

phragm
chamber
and

block

passage
of

vacuum
with
finger
When

connecting

rod
becomes
free
check
for
leakage
of

air
or

damage
to
diaphragm

Jets

Carburetor
performance
depend

on

jets
and
air
bleeds
That
is

why

these

components
must
be
fabricated

with
utmost
care
To

clean
them
use

cleaning
solvent
and

blow
air

on
them

Larger
inner
nwnbers

stamped
on
the

EF

29
jets
indicate

larger
diameters
Ac

cordingIy
main
and
slow

jets
with

larger
numbers

provide
richer
mixture

the
smaller
numbers
the
leaner
mix

ture

Conversely
the
main

and
slow
air

bleeds

through
which
air

to

passes

make
the
fuel

leaner
if

they
bear

larger

numbers
the
smaller

numbers
the

richer
fuel

Assembly

To
assemble
reverse

the
disassem

bly

procedure
taking
care
to
the

following

I
Thoroughly
wash
all
the

parts

before

assembling

2

Inspect
gaskets
to

see
if

they

appear
hard
or
brittle
or
if

edges
are

torn
or
distorted

If

any
of
such
undesirable
condi

tions
is

noted

they
must
be

replaced

3
Install

jet
and
air

bleed

having
the

Same
size

number
as
that
of

original

one

4

After
reassembling
carburetor

check
each

rotating
portion
or

sliding

portion
for
smooth

operation

Engine

fuel

TROUBLE

DIAGNOSES
AND

CORRECTIONS

In
the

following
table
the

symp

toms
and
causes
of
carburetor
troubles
and
remedies
for
them
are
listed
to

facilitate

quick
repairs

There
are
various

causes
of

engine

malfunctions

It
sometimes

happens

that
a

carburetor
which
has
no
fault

appears
to
have

some

problems
when

Condition
Probable

cause

Overflow

Dirt
accumulated
on
needle
valve

Fuel

pump
pressure
too

high

Needle
valve

improperly
seated

Excessive
fuel

consumption
Fuel
overflow

Slow

jet
too

large
on
each
main

jet

Main
air

bleed

clogged

Choke
valve
does

not

open
fully

Outlet

valve
seat
of

accelerator

pump

improper

Unked

opening
of

secondary
throttle
valve

opens
ioo

early

Power

shortage
Mainjels
clogged

Every
throttle
valve
Joes

not

open

fully

Idling
adjustment
incorrect

Fuel
filter

clo
ll
ed

Vacuum

jet
clogged

Air
cleaner

clogged

Diaphragm
damaged

Power
valve

operating
improperly

Improper
idling
Slow

jet

clogged

Every
throttle
valve

does
not
close

Secondary
throttle
valve

operating
im

properly

Throttle
valve
shafts
wom

Packing
between

manifold
carburetor

faulty

Manifold
carburetor

tightening

improper

Fuel
overflow

T

O
C
S

adjustment
incorrect

Vacuum
control
solenoid

damaged

Stuck
dash

pot

EF
30
acfuaJIy
theelectric

syslem
i
at
fatilt

Therefore

whenever
the

engine
is
mal

functioning
the

electrical

system

should
be
checked

fust
before

adjust

ing
carburetor

Corrective

action

Clean
needle
valve

Repair
pump

Replace

See
above

item

Replace

Clean

Adjust

Lap

Adjust

Clean

Adjust

Repair

Repair

Clean

Clean

Replace

Adjust

Clean

Adjust

Overhaul

and
clean

Replace

Replace

packing

Correct

tightening

See
the
first

item

Adjust

Replace

Replace

Condition

Engine
hesitation

Engine
does
not

start
Engine
Fuel

Probable

cause

Main

jet
or
low

jet
clogged

By
pass
hole
idle

passage
clogged

Emulsion
tube

clogged

Incorrect

idling

adjustment

Secondary
throttle
valve

operating
improp

erly

Fuel
overflows

No
fuel

Idling
adjustment
incorrect

Fast
idle

adjustment
incorrect

Damaged
anti
dieseling
solenoid

EF
31
Corrective
action

Clean

Clean
tube

Clean

Correct

adjustment

Overhaul
and

clean

See
the
first

item

Check

pump
fuel

pipe
and
needle
valve

Adjust

Adju
t

Replace

Emission
Control

System

CRANKCASE
EMISSION
CONTROL
SYSTEM

DESCRIPTION

This

system
returns
blow
by

gas
to

both
the

intake
manifold
and
carbure

tor
aitdeaner

The

positive
crankcase
ventilation

P

C
v
valve
is

provided
to

conduct

crankcase
blow

by
gas
to
the
intake

manifold

During
partial
throttle

operation
of

the

engine
the
intake
manifold
sucks

the
blow

by
gas
through
the
P

C
V

valve

Normally
the

capacity
of
the

valve

is

sufficient
to
handle

any
blow

by
and

a

small
amount
of

ventilating
air

L

J

J

o

I

Fresh

air

Blow

by
gas
The

ventilating
air
is

then
drawn

from

the
dust
side
of
the
carburetor

air

cleaner

through
the
tube
connect

ing
carburetor
air

cle
er
to
rocker

cover
into
the
crankcase

Under
full
throttle
condition
the

manifold
vacuum
is

insufficient
to

draw
the

blow
by
flow

through
the

valve
and
its

flow

goes

through
the

tube
connection
in
the

reverse
direc

tion

On
cars
with
an

excessively
high

blow
by
some
of
the
flow
will

go

through
the
tube
connection

to
car

buretor
air

cleaner
under
all
condi

tions

r

IiI
e
1

LJ

1

Seal

type
oil
level

gauge

2
DafOe

plate

3

Flame
arrester

4
Filter

5

P
C
V
valve

6
Steel
net

1
Baffle

plate

EC871

Fig
EC
5
Crankcase
Emis
ion
Control

Sy
tem

EC
6
INSPECTION

p
C
V
VALVE
AND
FILTER

With

ei
gine

runnirig
at
idle
remove

the
ventilator
hose
from
P

C
V

valve

if
the
valve
is

working
a
hissing
noise

wiD
be
heard

as
air

passes
through
the

valve
and
a

strong
vacuum
should
be

felt

irnniediately
when
a

fmger
is

placed
over
valve
inlet

EC139A

Fig
EC
6

Checking
PC

V
Vo
ve

VENTILATION

HOSE

I
Check
hoses

and
hose
connec

tions
for
ieaks

2
oisconn
ct
all
hoses
and

clean

with

compressed
air

If

any
hose

cannot
be

free
of

obstructions

replace

Ensure
that
flame

arrester
is

surly

inserted
in

hose
between

air
cleaner

and
rocker
rover

ET277

Fig
EC

7

Checking
Ventilation
Hose