1979 DATSUN 210 check engine light

Not

Pump
rotors
and

body
are
not
serv

iced

separatdy
If

pump
rotors
or

body
are

damaged
or

worn

replace

ment
of
the
entire
oil

pump
assembly

isnecessary

OIL
PRESSURE

REGULATOR
VALVE

The
oil

pressure
regulator
valve
is

not

adjustable
At
the
released

posi

tion
the
valve

permits
the
oil
to

by

pass
through
the

passage
in
the

pump
cover
to
the
inlet
side
of

the

pump
Check

regulator
valve

spring
to

ensure

that

spring
tension
is
correct

no

1

Regulator
valve

2
Relief

valve

3
Valve

spring
E
L045

Fig
EL
5

Regulator
and
Reli
Vatv
Engine
Lubrication
System

8Peciflcatlons

Oil

pressure

At

idling

more
than

O

Blrg
an2
11

psi

At

3
000

rpm

3
B
to
5
2lrg

an2

54
to
74

psi

Regulator
ai

spring

Free

length

43
49
rom
1
7122
in

InstoJlod
l

ngth
load

30
3
mm
3
67

kg

1
193

inJB
09lbl

Regulator
val

o

ning
pressur

3

8
to
4
2

lrg
an2

54
1060

psi

OIL
PRESSURE

RELIEF
VALVE

The
relief
valve
located
in

the
oil

pump
cover

by
passes
the

oil
into
the

main
oil

gallery
when

the
oil
filter

elem
nt
is

exCessively
clogged
With

regula
tor
valve
removed
check
valve

for

operation
See

Fig
EL
5

OIL
FILTER

tEMOVAL

Place
a
suitable
container
under
the

f1lter

Unscrew
f1lter
from
oil

pump
cover

flange
using
Oil
Filter
Wrench

STl9320000

EL
4
Fig
EL
6

Removing
Oil
Filter

INSTALLAnON

I
Coat

the

packing
on
the
new

f1lter
with

oil
Position
the

f1lter
on

the
oil

pump
cover

flange
Hand

tight

en
the
f11ter
until
the

packing
contacts

the

cover

flange
then
advance
it

2
3

tum

Note
Do
not

overtighten
the
fiIter

or

oil
leak

may
occur

2

Operate
the

engine
at
fast
idle

and
check
for
oil
leaks
Check
the
oil

level
and
add
oil
if

necessary

OIL
PRESSURE

WARNING

SWITCIt

The
oil

pressure
warning
switch
is

located

on
the

oil

pump
cover
and

wired
to

an
instrument

cluster
See

Fig
EL
6

The

warning

light
glows
whenever

the

oil

pressure
drops
below
0

2
to
0
4

kg
cm1
2
8
to
5
7

psi

Prior
to

installing
a
switch
to
cover
I

be

sure
to

apply
a
conductive
sealer

to

threads
of

switch

DASH
POT
SYSTEM

These

carburetors
are

equipped

with
a
dash

pot
interlocked
with
the

primary
thrott
Ie
valve

through
a

link

mechanism

The
dash

pot
prevents
the

throttle

valve

from

closing
abruptly
thereby

reducing
He
emissions

during
deceleia

tion
or

gear
shifting

In
automatic

transmissi9fi
models

it

also

prevents
engine
stall

resulting

from

quick
application
of
the
brake
or

from

quick
release
of
the

accelerator

pedal
after
it
s
been
tread

upon

slightly

INSPECTION

AND

ADJUSTMENT

CARBURETOR
IDLE
R
P
M

AND
MIXTURE
RATIO

CO
idle
adjustment
with

CO
meter

Refer
to
Carburetor
Idle

rpm
and

Mixture
Ratio
Section
ET
for
check

ing
and
a

justment

CO
idle

adjustment
without

CO
meter

Non
California
models

Refer
to

Carburetor
Idle

rpm
and

Mixture
Ratio
Section

ETl
fot
check

ing
and

adjustment

Idle

limiter

cap

Refer
to
Idle

Limiter

Cap

SeCtio

ET
for

checking
and

adjustment

FUEL

LEVEL

I

With

engine
idling

visually
check

fuel
level

through
sight
window
of

float
chamber

Fuel
level
is
correct

if
it

is
at
the

indicator

point

Note

Fuel
level
indicator

point
is

located
IS
mm
0
59
in
below

top

of
carburetor

body
H

as
shown
in

Figure
below
Engine
Fuel

EF088A

Fig
EF
33

Checking
Fuel
Level

To

adjust
fuel
level

proceed
as

follows

2

Remove
choke

chamber

3

Turn
down

choke
chamber

to

allow

float
to

come
into
contact
with

needle

valve
and

measure
H

shown

below

When
H

is

approximately
15
mm

0
59
in

top
float

position
is
correct

The

top
float

position
can
be
ad

justed
by
bending
float
seat

Upon

completion
of
the

adjust

ment

check
fuel

level
with

attached

level

gauge

nhH

J

1
Float

2
Float

stopper
3
Float

seat

4
Needle
valve

Fig
EF
34

Adjusting
Floot
Level

EF

14
4

Adjust
bottom
float

position
so

that
clearance

hl
between

float

seat

and
needle

valve
stem
is
1
3
to
I
7
mm

0
051
to
0
067
in
when

float
is

fully

raised
Bend
float

stopper
as

required

5

Install
choke
chamber

6
After

adjustments
in

steps
3
and

4
above
have
been

made
make

sure

that
when
fuel
is
delivered
to
the

float

chamber
the

fuel
level

is
maintained

within
the

specified
value

H

Engine
Fuel

Upon
completion
of

adjustment

make
sure
that

link

system
opera
tes

smoothly
It
is

necessary
to
remove
Carburetor

from

engine
in

adjusting
this
accelera

tor

pump
stroke
limiter

1

Remove
carburetor

from

engine

2

Insert
a
l
l

to
I
S
mm
0

043
to

0
059

in
feeler

gauge
a

piece
of

round

stock
of

proper
thickness
is

best

betwee
l
primary
ca

buretor

throat
and
throtile
valve
ACCELERATOR
PUMP

STROKE

LIMITER

In

rmal
service

operation
this

limiter
should

not
be
removed
or

bent

In
J

0

ID

@

l

1IJl

J
J
00

I
f

oj

G
1
3
IO
2

mm
0
051
IO
004
in

Fig
EF
44
AdjlUting
Acce
rator

Pump
Stroke
Limiter
1
Primary
carburetor
throat

2
Throttle
valve

3
Lever

4

Limiter
5
Piston

6

Pin

7
Feeler

gauge

E
F048A

3

With
throttle
valve
held

open

properly
by
feeler

gauge
check

that

lever

barely
contacts

pin
If
lever
and

pin
are
not
in

contact

bend
limiter
until

proper
contact
is

made

OZ
00
A

fID

1

S

@

4
1

Full

travel
of

lever

f

EF049A
A
1
Lever

2
Correct

contact
area

3
Limiter

4
Pin

5

Pistgn
6
Correct
cont
ct
area

7
Lever

8

Limiter

9
Pin

10
Piston

Fig
EF
45
Stroke
Limiter

DASH

POT

I

Idling
speed
of

engine
and
mix

ture
must

be
well

tuned

up
and

engine

sufficiently
warm

2
Turn
throttle
valve

by
hand
and
read

engine
speed
when
dash

pot
just

toucnes

stopper
lever

3

Adjust
position
of
dash

pot
by

tuming
nut
until

engine
speed
is

in
the

specified

range

California

models
Non

Califomia

models

Automatic

transmission
1

900

to
2

100
1
900
to

2
100

Manual
transmission

1
900

tp
2

100
2
300

to
2

500

FU
model

1

900
to
2

100

EF

t8
1
Lock
nut

2
Dash

pot

E

F730

F
ig
EF
4

Ll
dj

ting
h

P
ot

4

Tighten
lock
nuts

5

Make
sure
that

engine
speed

drops
smoothly
from
2

000

to
1
000

rpm
in

about
three

seconds

ACCELERATING
PUMP

I

Visually
inspect

accelerating

pump
cover

for

any

sign
of
fuel

leaks

2

If
fuel

leaks
are
found

check

gasket
and

replace
if

necessary

3

Turn
throttle

valve

by
hand

make
sure
fuel
is

injected

through

injector
nozzle

Note
To

check
or

fuel

injection

peep
into
nozzle
rom

upper
side

while

directing
flashlight
beam
to

ward

primary
barrel

ANTI
DIESELING

SOLENOID

VALVI

Start
the

engine
and

keep
at

idling

speed
Disconnect
the

lead
w

e
for
the

anti
dieseling

solenoid
at
the

connec

tor

If
the

engine
does

not

stop
when

the
lead

wire
is

disconnected
the

solenoid
is

stuck
Reconnect
the
lead

wire
and

start
the

engine
Then
turn

off
the

ignition
switch

If
the

engine
does
not

stop
when

the

ignition
switch
is
turned
off

this

indicates
that
the

striking
solenoid

valve
is

stuck
or

short

circuited

If
the

harness
i
in

good
condition

replace
the
solenoid
valve
as
a
unit

them

b
If
carbon
shoes
are

exposed
beyond

the
rotor
end
face
remove
carbon

shoes
and
clean
shoe

grooves
Reas

semble
carbon
shoes

6

Vane

1
Pack

vane

bearing
with

high

melting

poinf
grease
MIL
G
3S45
A

Es

o
ANDOK260
or

equivalent
and

insert

dummy
shaft
into
the
vane

bearing

STl9900000

EC563

Fig
EC
40

Va
Assembly

2
Install
vane
in

place
on
rotor

uMng
Dummy
Shaft
STl9900000
as
a

guide

Note
The
woes

may

require
6
to
16

km
4
to
10
miles
wear
in
running

time
In
the
event

a

slight
squeaking

still
remains
drive
the
car

about
64

to
80

km
h
40
to
SO
MPH
In

most

cases
6

to
16
km
4
to
10

miles
will
be
sufficient
for
wear
in

7

Shoe

spring

Place
shoe

springs
in

deeper
groave

of
shoe

11

I

11

1

EC123

Fig
EC
4I
Ins

tolling
Shoe

Spring

Note
When

installing
a

shoe

spring

make
sure
that
the
outward
bend

ing
side
faces
in
shoe
and
that
both

ends
of

sJlri
face
in
the
wall
of
Emission
Control

System

shoe

groove
6e
Sure
to

push
spring

in

SO
that

spring
end
face
is
flush

with
rotor

8
Rotor

ring

Install
rotor

ring
by
correctly

align

ing
the
rear
end
face
of
rotor
with

the

on

mark
in
rotor

ring
and

tighten

screws
with

Hexagon
Wrench

ST
98
10000

l
l
Tightening
torque

Rotor

ring
screw

0
5
to
0

7

kg
m

13

6
to
5
1
ft
lb

Fig
EC

42
Installing
Rotor

Ring

9
Removal
of

dummy
shaft

CarefuDy
withdraw

dummy
shaft

from
vane

10
Vane
shaft

Pack
rear

bearing
with

high

melting

pain
t

grease
MIL
G
3S45
A

Esso
ANDOK
260
or

equivalent

Apply
thin

coating
of

grease
to
vane

shaft
and

rotor
ring
and
insert

vanf

shafi
into
its

bearing

Note

a

Do
not

apply
an
undue
stress
to

vane
shaft
when

inserting

b
If
two
vanes
are
dislocated
when

inserting
vane
shaft

correctly
align

Yanes

by
inserting
dummy
shaft

Then
draw
out

dummy
shaft
and

insert
vane
shaft

c
When
wear
occurs
on

vane
shaft
or

when

replacement
of
rear

bearing
is

necessary
replace
rear
rover
assem

bly

J
I

End
cover

Position
end

cover
in

place
Snugly

tighten
the
bolt
close
to
the
dowel

Then

tighten
end
cover

bolts

EC
t6
l
l
Tighteningtnrque

End
cover
bolts

0
7
to
0
9

kg
m

5
1

to
6
5
ft
bl

EC302

Fig
EC
43
lnstolling
End
Cover

12

Pulley

Tighten

pulley
securing
bolts

Tightening
torque

Pulley
securing
bolts

0
75

to
0
90

kg
m

5
4

to
6
5
ft

Ib

INSPECTION

The
following

procedures
are
re

commended
for

checking
and
or

as

certaining
that
the
various

components

of
the

exhaust
emission
control

system

are

opera
ting
properly

The

engine
and
all

components

mu
t
be
at
normal

operating

tempera

tures
when
the
tests
are

performed

Prior
to

performing
any
extensive

diag

nosis
of
the
exhaust
control

ystem
h

must

be
determined
that
the

engine
as

a
unit
is

functioning
properly

Air

injection
s

stem
hoses

Check
air

system
hoses
for
loose

connections
cracks
or
deterioration

Retighten
01

replace
if

necessary

Air

pump

I

Operate
engine
until
it
reaches

normal

operating
temperature

2

Inspect
all
hose
hose
connec

tions
and
air

gaDery
for
leaks
and

correct
if

necessary
before

checking

air

injection

pump

3
Check
air

injection
pump
belt

tension
and
adjust
to

specifications
if

necessary

4

Plug
up
air

discharging
hose

from

C
A
C
valve
California
models

y

o

EC144A

Fig
EC
44

Plugging
C
A

C
Value

Air

Discharging
Hose

California
model

S

Disconnect
air

supply
hose
at

check
valve

6
Insert

open
pipe
end
of
Air

Pump

Test

Gauge
Adapter
STl9870000
in

air

supply
hose

Clamp
hose

securely

to

adapter
to

prevent
it
from

blowing

out
Position
adapter
and
test

gauge
so

that
air
blast
emitted

through
drilled

pipe
plug
will
be

harmlessly
dissipated

7
Install
a
tachometer
on

engine

With
the

specified
engine
speed
ob

serye
air

pressure
A

produced
at
test

gauge

Air

pressure
A

More
than

100

mmHg
3
94

inHg

at
2
600

rpm

I

jff

100
m

Hg

f1

3
94

mHg

I

EC145A

Fig
EC
45

Testing
Air

Pump

8
If
air

pressure
does
not
meet

above

specifications
proceed
as

follows
Emission

Control

System

Non

California
models

1
Repeat
2

and
3
above

2
With

engine
speed
at
1
500

rpm

disconnect
tube

from

adapter
and

close
hole
of

test

gauge
with

finger
If

a

leaking
sound
is
heard

or

leaking
air

is
felt

by
finger
at
relief
valve
relief

valve
is

malfunctioning
Relief
valve

should
be

replaced
or

repaired

3
If
air

injection
pump
does

not

meet
minimum

requirement
of

pres

sure
test
it
should
be

repaired

California
models

Disassemble
the
air

pump
and
re

pair
it

Check
valve

Warm

up
engine
thoroughiy

2
Disconnect

hose

leading
to

check

valve
from
air

hose
connector

3
Check
hose

opening
for

any
indi

cation
of
exhaust

gas
leaks
If
leaks

are

detected

replace
check
valve

4
Race

the

engine
lightly
at
about

2
000

rpm
and
then

return
it
to

idling
Visually
check
the
hose
for

any

indication
of
exhaust

gas
leaks

before

the

engine
returns
to

idling
speed
If

leaks
are
detected

replace
check
valve

EC146A

Fig
EC
46

Checking
Check
Valve

Air
pump
relief
valve

After

completing
inspection
of
air

pump
check
air

pump
relief

valve
in

the

following
steps

I
Disconnect
hoses

leading
to
check

valve
and
air
control
valve
from
air

hose

connector
and
install

blind
c

p

to
the
connector

2
With

engine
running
at
about

3
000

rpm
under

no
load

place
your

EG
7
hand
on
the
air
outlet
of
air

pump

relief
valve
to

check
for

discharged
air

If

no
air
is
felt

replace
the

air

pump

relief
valve

G

EC575

Fig
EC
47

Checking
Air

Pump

Relief
Valve

Anti
backfire
valve

A
B

valve

I
Warm

up
engine
thoroughly

2
Disconnect
hose
from
air

cleaner

and

place
a

finger
near
the

outlet

3
Run

engine
at
about
3

QOO
rpm

under
no

load
then

quickly
return
it

to

idling
If

you
feel
a

pull
or
suction

force
on

your
finger
the
anti
backfire

valve
is

functioning
normally
If

no

suction
is

felt

replace
the
anti
backfire

valve

EC768

Fig
EC
48

Chocking
Anti

backfire

Valve

C
A
C
valve

California
models

I

Make
sure
that

C
A
C

valve
vacu

um

hose
and
air

hose
are

not
cracked

2
Warm

up
engine
throughly

3
With

engine
at
idle

place
your

fmger
over

relief
hose

opening
to

check
for

presence
of
air

4

With

engine
idling
disconnect

vacuum
hose
at
C
A

C
valve

Then
make

sure
that
air
is

discharg

ed
from

C
A
C
valve

C

A
C
valve
is

functioning

properly

if
air
is

discharged
from
it

CAUTION

Do
not
allow
water
to

get
inside
the

thermal
vacuum
valve

EC161A

Fig
EC
77
Ch

c

jng
Th
rmal
Vacuum

Valve

3

port
type

Thermal

vacuum

valve

2

port
type

Dismount
thermal

vacuum
valve

from

engine

Note

Before

dismounting
drain
en

gine
c
oolant
from

engine

Apply
vacuum
to
thermal

vacuum

valve
and

check
to
be
sure

that
ther

SPARK
TIMING

CONTflOL

SYSTE
VI

DESCRIPTION

The

spark

timing
control

system
is

designed
to
control

the
distributor

vacuum
advance

under

varying

driving

conditions
so

as
to
reduce
He
and

NOx
emissions
Emission
Control

System

mal

vacuum
valve

opens
or
closes
in

response
to

engine
coolant

tempera

ture

as

specified

Thermal

vacuum
valve

should

open

at

a

temperature
specified
below

com

pleting
the
vacuum

passage

Thermal

vacuum
valve

opening

temperature

40
to

63
c
104
to
1450

Fl

CAUTION

00

not
allow
water
to

get
inside
the

thermal1
acuum
valve

Jl
i

g

J

eC
42

Fig
EC
78
Ch

ckjng
Thermal
Vacuum

Valve

M
T
model

When

the
transmission

is
shifted

into
the

4th
or
5th

gear
the
electric

current
flows
into

the
vacuum

switch

ing
valve
The
vacuum

switching
valve

is

then
actuated
and

close
the
vacuum

passage
As

a

res
li
the

distributor

fully
advances

its

ignition

liming

When
the
transmission
is

shifted

into

any
gear
other

than
4th
and
5th

current
flow
is

interrupted
The

vacu

umswitclting
valve
is

then
deactuated

and
the

vacuum
leak

passage
is

E026
BoP

T
valve

1

DiSCOIUlect
two
vacuum
hoses

on

BY
T
valve

2

Plug
one
of
two

port
of
BY
T

valve

Apply
a

pressure
above
SO

nimH20

1
97

inHP
to
B
P
T
valve
and

orally
suck
back
other

port
of
B
P
T

valve

as
shown
below

to
check
for

leakage
If

a
leak
is
noted

replace

valve

Apply
pressure
above

SO
mmH10
2
inH10

EC311A

Fig
EC
79

Checking
B
P
T
Valve

opened
This
weakens
the
vacuum

signaUransmitted
from
the
carburetor

As
a
result
the

ignition
timing
of
the

distributor
is

slightly
advanced

On
U
s
A
models

except
for

the

FU
model
a
thermal

vacuum
valve

3

port
type
is
added
on
the

vacuum

line
between
the
carburetor
and
dis

tributor

The
vacuum

signal
is
controlled

by

this
thermal

vacuum
valve

in
accord

ance
with
variation

in

engine
cooling

water

temperature

INSPECTION

Entire

system

U
S
A
MIT

models

except
FU
mo

el

1
Ensure
that

wiring
connectors
are

tight
in

pla
ce

2
Ensure
that

vacuum
hoses

are

properly

cof
1o
c
ed
to

their

positions

3
Ensure
that
distributor
vacuum

controller

properly
functions

4

Set

timing
light
and
start

engine

S

While

engine
cooling
water
tem

pefature
is
below

SOOC

I220F

check
function
of

system
as
follows

WARNING

To

protect
against
accidental
for

ward

surge
engage

parking
brake

firmly
while
above
check
is

being

made

I
Run

engine
and

keep
it

at

ap

proximately
1
600

rpm

2

Disengage
clutch
Shift

gears
in

top
3rd
then
neutral

positions
Read

spark

timing
in

respective
shift

posi

tions

The

system
is

properly

functioning

if

spark
timir
g
does
not

change

If
t

changes
check
thefmal
vacuum

valve

3

port
type

Note

Ensure
that
thermal
vacuum

wIve

is
closed
when

cooling
water

i
below

5
to
lSoC
41
to

640F
or

above
SO

to
630C
122
to
14S0F

I

6

After
the

engine
has
been

warmed

up
sufficiently
check
the

function
of
the

system

again
in
the

I

Same
manner

The

system
is

properly
functioning

if

spark
iimin
advances
in

top
posi

tion

If

not
check
thefmal
vacuum
valve

control

circuit
or
vaeu
um

switching

valve

Entire

system

FU
model
and

Canada
MIl
models

I
Ensure
that

wiri
lg
connectors
are

tight
in

place
Emission

Control

System

2

Ensure
that

vacuum

hoses
are

properly
connected
to
their

positions

3

Ensure
that

distributor
vacuum

controller

properly
fu
ctions

4

Set

timing
light

WARNING

To

protect

against
accidental
for

ward

surge
engage
parking
brake

firmly
while
above
check

is

being

made

5
Run

engine
and

keep
it
at

ap

proximately
1
600

1
m

6

Disengage
clutch
Shift

gears
in

4th

5th
ihen
neutral

positions
Read

spark
timing
in

respective
shift

posi

tions

The

system
is

properly
functioning

if

spark
timing
advances
in

top
gear

position

If

spark

timing
does
not

vary
at
all

in

tests
des
rilied

in

step
6
above

check

control
circuit
or

vacuum

switching
valve

Entire

system

California
AIT
models

I
Ensure
th
t

wiring
connectors

are

tight
in

place

2

Ensure
that
vacuum
hoses
are

properly
coIDwcted
to

thejr
positions

3

Ensure
that

distributor
vacuum

controller

function
s

properly

4
Set

timing
light
and
staft

engine

S

While

engine
cooling
water
tem

perature
is
below
SOOC
1220F

check
the
function
of
the

system
as

follows

WARNING

To

protect
againSt
accidental
for

ward

surge
engage

parking
brake

firmly
while
above
check
is

being

made

I
Run

engine
and

keep
it
at

ap

proximately
1

600

rpm
at
P

range

2

Make
a

short
circuit

between
the

specified
two
terminals
at
function

te
t

connector

EC31
The

entire

system

except
for
the

top
switch
is

properly

functioning
if

spark
timing
does
not

change
If

it

changes
check
the

thermal
vacuum

valve

3

pori

type

CAUTION

Pay
attention
not
to
make
a
short

circuit
between
other
terminals
than

the

specified
terminals
or
electrical

system
of
car
will

get

damaged

4

EC328A

Fig
EC
94

Making
Short
Circuit

6

After
ihe

engine
has
been

warmed

up
sufficiently
check
the

function
of
the

system
again
in
the

same
manner

The

system
except
for
the

top

switch
is

properly

fU
lctioning
if

spark

timing
is

approximately
greater
than

that
without

a
short
circuit

If

not
check
the

thermal
vacuum

valve

control
circuit
or

vacuum
switch

ing
valve

7
As
the
final

step
of

checking

entire

system
top
switch
should
be

checked

as
follows

1
Start

engine
and

keep
at

idling

speed

2

Disconnect
lead
wires
from
vacu

um

switching
valve

at
connetors

CAUTION

Never

forget
this

operation
otherwise

the
circuit

tester
will

get
damaged

EC173A

Fig
EC

95

Disconnecting
Vacuum

Switching
Valve
Connector

3

Apply
parking
brake
and

keep

brake

pedal
fully

depressed

4

Check

continuity
between
two

specified
terminals
ai

function
test

connector
with

gearshift
lever
in
R

or
N

position

The

top
detecting
switch
is

func

tioning
properly
if
the

continuity
is

as

following
table

If
not

replace
the
switch

N

position
No

R

position
Yes

Note
At

idling

CAUTION

Never

race
the

engine
or
car
will

creep

r

q

EC329A

Fig
EC
96

Checking
Top

Detecting

Switch

Arr
model
Emission
Control

System

Entire

system

Non
California
AfT
models

except
Canada

1

Ensure
that
vacuum

hoses
are

properly
connected
to

their

positions

And

confirm
that

gearshift
lever
is
in

P

position

2
Disconnect

vacuum
hose
atdis

tributor

vacuum
controller

3

While

engine
cooling
wat
r

is
be

low
SOoC

1220F
race

engine
and

check
vacuum
for
distributor
If
vacu

um
is
felt
check

thermal
vacuum
valve

3

port
type

4

After

engine
is

sufficiently

warmed

up
repeat
the
above

opera

tion

In

this
case
vacuum
should
be
felt

If
not
check
thermal

vacuum
valve

Vacuu
m

switching
valve

If

spark
timing
does
not

vary
at
all

in

checking
entire

system
check
vacu

um

switching
valve
i
follows

I
Warm

up
engine

sufficiently

2

Disconnect

vacuum

switching

valve

lead
wires

3

Set

timing
light
and

keep
engine

speed
at

approximately
1

600

rpm
On

AfT
models

geaishiftlever
should

be

in

N
or
P

4

Apply
l2V

battery
voltage
to

one
of
two

lead
wires

from
vacuum

switching
valve
Then
connect
the

other
lead
wire

to

ground

At

this
time

spark
timing
should

change

appioximately
by
50

If
it
does
not

replace
vacuum

switching
valve

EC175A

Fig
EC

97

Checking
Vacuum

Switching
Valv

Thermal
vacuum
valve

3
port

type
U
s
A
models

except
FU

model

Remove

thermal
vacuum

valve
from

engine
Inhale
air
from

port
of

spark

EC32
timing
amttol

systetn
andcheck
to

sure
that

thermal
vacuum
valve

opens

or
closes
in

response
to
its

tempera

ture

Thermal

vacuum
walye

closing

temperature

Above
50
to

63
c

122
to
1450
F

Below
5
to

1SoC

41
to

64
Fl

J

EC161A

Fig
EC
98

Checking
Thermal

Vacuum

Valv

CAUTION

Do

not
allow

water
to

get
inside

the

thenna

vacuum
valve

Top
detecting
switch

M
T
models

To

check

top
detecting
switch
for

proper
ON
OFF

operation
contact

leads
of

an
ohmmeter

with
swiich

lead

wires
and
shift
transmiosion

from

TOP
to
other
forward

gear
and

vice

versa
If

switch
does
not

operate
prop

erly
replace

Continuity
of

top
detecting
switch

should
be

a
follows

Other
than

4th
and
5th
No

4th

and
5th

Yes

Note
In

checking

continuity
oCthe

switch

keep
the

ignition
switch

OFF
Otherwise
the

circuit
tester

will

get

damaged