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Air
control
valve

CalifornIa
models

The
air
control
valve

con
troIs
the

quantity
of

secondary
air
fed

from
the

air

pump
according
to

engine
speed

and

load
condition
and

prevents
ex

cessive

temperature
rise
of
the

cataly

tic
converter

The
construction
is
as
shown
in

Figure
EC
16
The
intake
manifold

vacuum
and
air

pump
discharge
pres

sure

applied
to

the

diaphragm
chamber

actuate
the

valve
which
is

coupled
to

the

diaphragm
and
control
the

quanti

ty
of

secondary
air
to
be
fed
into
the

exhaust
manifold
in

response
to
the

engine
condition

c
From

air

pump

To

carburetor

air
cleaner

lr

J

EC291

Fig
EC
16
Air
control
valve

Anti
backfire
valve

This

valve
is

con
trolled

by
intake

manifold
vacuum
to

prevent
backfire

in
the

exhaust
system
at

the
ini

tial

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

A
schematic
drawing
of
the
anti

backfire
valve
is
shown
in

Figure

EC
17

The
anti
backfire
valve
inlet
is

con

nected
to
the
air
cleaner
and
the

outlet

to
the
intake
manifold

Th
correct
function
of
It
jS
valve

reduces
hydrocarbon
emission

during

aeceleration

If
the
valve
does
not
work

properly

unburned
mixture
will
be

emitted
Emission
Control

System

from
the
combustion
chambers
and

burns
with
the
aid
of
high

temperature

and

injected
air

which
causes
backfire

I
Tointake

c
manifold

vacuum

I

L

AirdisChaJ1le

I

to
mtake

manifold
From
air

cleaner

ECQ69

Fig
EC
11
Anti
back
ir
valve

Check
valve

A
check
valve
is
located
in
the
air

pump
discharge
lines
The
valve

pre

ven
ts
the
backflow
of
exhaust
gas

which
occurs
in

one
of
the

following

cases

1
When

the
air

pump
drive
belt

fails
2
When
relief
valve

spring
fails

Construction
is

shown
in

Figure

EC

18

F
rom

m

pump

1

Spring

2

Rubber
valve

3

Seat
Secondary
air

Exhaust

gas

EC292

Fig
EC
1B
Check
valve

AIr

InJaction
Into
axhaust

port

The

secondary
air

fed
from
the
air

pump
goes
through
the

check
valve
to

the
air

gallery
where
it
is
distributed
to

each
exhaust

port
The

secondary
air

is
then

injected
from
the
air

injection

nozzle
into

the
exhaust

port
near
the

exhaust
valve

n

L
y

r

V

Air
pump
relief
valve

The
air

pump
relief
valve

controls

the

injection
of
the

secondary
air
into

the
exhaust

system
when
the

engine
is

EG
11
3
I
Air

gallery

2

Exhaust
port

3
Air

jnjection
nozzle

4
Exhaust

manifold

EC293

Fig
EC
19
Air
injection
into
exhaust

port

running
at

high
speed
under
a

heavily

loaded
condition
It

accomplishes
the

following
functions
without

affecting

the

effectiveness
of
the
exhaust
emis

sion
control

system

Minimizes
exhaust

gas
tempera

lure
rise

2
Minimizes

horsepower
losses
re

suiting
from
air

injection
into
the

exhaust

system

3
Protects

pump
from
excessive

back

pressure

The
air

pump
relief
valve
is
installed

as
shown
in

Figure
EC

20

The

secondary
air
is

discharged

from
the
air

pump
relief
valve

to
the

dust
side
of
the
carburetor
air
cleaner

To
carburetor

air
cleaner

Secondary

air

To
carburetor

air

cleaner

J
erCOndary

r

r

EC294

Fig
EC
20
Air

pump
relief
valve
Emission
Control

System

Emargency
air
retial
valve

E
A
R
Valve

California
models

The

emergency
air
relief
valve
con

trols
the

quantity
of
secondary
air

fed

from
the
air

pump
according
to

load

condition
and
it

discharges
the
see

ondary
air
into
the

atmosphere
to

prevent
overheating
of
the

catalytic

converter

The

emergency
air
relief
valve
con

sists
of
a

diaphragm
a

spring
and

a

valve
which
is

coupled
to

diaphragm

1

Diaphragm

2

Val

3

Spring

4

Diaphragm
chamber

EC536

Fig
EC

21

mergency
air

relief
valve

OPERATION

As
mentioned

previously
there

are

two

types
of
Air

Injection
Systems

A
I

S
a

non
California

type
and
a
California

type
The
California
stand

ard

type
includes
a

system
which

controls

injection
of

secondary
air

so

as
to
assure

proper
function
of
the

catalytic
converter
and
a

system

which
controls
the

supply
of
second

ary
air
to

prevent
abnormal

tempera

tUfe
rise
in
the

catalytic
converter

The
A
I
S
consists
of
the

following

systems

L
A

system
which
allows

injection

of

secondary
air
into
the
exhaust

port

2
A

system
which

bypasses
sec

ondary
air

from
the
air

pump
relief

valve

to
the

carburetor
air

cleaner

during

high
speed
engine
operation

3
A

system
which

supplies
air

from

the
carburetor
air
cleaner

to
the
intake

manifold

by
means
of
the
anti

backfire

valve
so
as
to

prevent
after
fire

during

deceleration

4
A

system
which

controls

injection

of
the

secondary
air

by
means
of
the

air

control
valve

so
as
to
maintain
the

catalytic
converter
at
an

optimum

temperature
level
under

lightly
loaded

condi
tions

Califomia

type
only

5
A

system
which
controls
the

sup

ply
of

secondary
air

through
the
emer

gency
air

relief
vilve

io
pfevent
ab

normal

temperature
rise
of
the

cataly

tic

converter

California

type
only

A
I

S

operation
is

as
follows

I

I

t

1
r

9

I
Air

pump
6

Check
valve

I
0
L
2
Air

pump
air
deaner
7
Air

gallery
pipe

3
Air

relief
valve
8
Injection
non
e

r
4
Air
cleaner
9

Exhaust
manifold

5

Carburetor
10

Anti
backflIe
valve

EC179

Fig
EC
22
Non

California
type
A
I
S

EC
12

The
non
California

type
operates
as

follows

secondary
air
is
sucked

through
the
air

pump
air

cleaner
into

the
air

pump
driven

by
the
crank

pulley
It
is

then

discharged
through

the

check

valve
to

the
air

gallety
where

it
is

distributed
to
each

exhaust

porL

The

secondary
air
is
then

injected

from
the

injection
nozzle

into
the

exhaust

port
near
the
exhaust
valve

The
air
relief
valve

opens
only
when

the

discharge
pressure
of
the
air

pump

surpasses
the

spring
force
of
the
air

relief
valve

during
high
speed
opera

tion

When
the
air

relief
valve

opens

the

secondary
air
is

discharged
in
to

the

carburetor
air
c1eaner

The
anti

backfire
valve

opens
when

the
intake
manifold
vacuum

reaches
a

predetermined
value

during
decelera

tion

and

permits
fresh
air
to
now
into

the
intake

manifold
from
the
air

cleaner

f

I

Jl

rn
l

I
Air

pump

2
Air

pump
air

cleaner

3

Emergency
air

relief
valve

4

Air

relief
valve
riu

Qj

j

I

@
Emission
Control

System

To
intake

manifold

The
California

type
includes
in

addition
to
the

components
of
the

non
California

type
an

air

control

valve

and
an

emergency
air
relief
valve

The
air

control
valve

opens
when

the
sum
of
the
air

pump

discharge

pressure
and

the
intake

manifold
vacu

um

applied
to
the

diaphmgm
reaches
a

predetermined
level
and

discharges

the

secondary
air
into
the

air
cleaner

When
the

pressure
becomes
low
the

valve
doses

with
the

spring
force
of

3

5
Air

cleaner

6

Check
valve

7

Air

gallery

pipe

8

Carburetor

EC

13
To

intake

manifold

Air

diSlcharge
to

intake
manifold

Secondary

air

EC297

Fig
EC

23

Operation

of
A

B
lve

the
air
control
valve

and

stops
dis

charging
the

secondary
air

F
igure

EC

25

When
the

intake
manifold

vacuum

applied
to
the

diaphragm
reaches

a

predetermined
level
E
A

R
valve

operates
to

discharge
the

secondary
air

into
the

atmosphere
When
the

pres

sure

becomes

high
the
valve

closes

by

spring
tension
of
E
A
R
valve

and

stops

discharging
the

secondary
air

fl

t

9
Air
control
valve

10

Injection
nozzle

II
Exha
l
t

manifold

12
Anti
backfire
valve

EC780

Fig
EC
24

California

type
A
I

S

9
From
air

pump

l

h
1

Not
actuated

REMOVAL
AND

INSTALLATION

Air
p
mp
sir
cleaner

Remove
air
hose

then
detach
air

cleaner

from

hoodledge
Air
cleaner

element
and
Ii
r
deancr
lower

body
are

built
into
a
unit
construction

Replace

air
cleaner
clcl

nen
and

lower

body
as

an

assembly

J

J

tt
c

t
o

J

EC
323

Fig
EC
26
Replacing
oir
cleaner

element

Air

pum

Remove
air
hoses

from
air

pump

2
Loosen
air

pump
adjusting
bar

mounting
bolts
and
air

pump
mount

ing
bolts
then

remove
air

pump
drive

bell

3
Remove
air

pump
pulley

4
Remove
air

pump
from
bracket

Air
control
valve

California
models

l
Disconnect

air
hoses
and
a
vacu

um
hose
from
air
control
valve

2
Remove
air
con
trol
valve
from

bracket

E
A

R
valve
California
modela

Remove
vacuum

pipe
and
air

hose

and
dismount
E

A
R
valve
Emission
Control

System

o

jJ
To

Intake
mamfold

rF
vacuum

r

To
air

cleaner

From
air

pump

EC781

Fig
EC
27
Locotion

of
E
A
R
wive

Antl
backflravalve

Disconnect
air
hose
and
vacuum

hose
from
anti
backfire
valve

Check
valve

Disconnect
hose
and
remove
check

valve
from
air

gallery
pipe

Air

ganery
pIpe
andinJactlon

nozzles

It
is

very
difficult
to
remove
the
air

gallery
from
the
exhaust
manifold

without

bending
the

pipe
which
could

result
in
fractures
or

leakage
There

fore

removal
of

the
air

gallery
pipe

and

injection
nozzles
should
be
under

taken

only
when

they
are

damaged

I
Lubricate
around
the

connecting

portion
of
air

injection
nozzle
and
air

gallery
with

engine
oil

2
Hold
air

injection
nozzle

hexagon

head
with
a

wrench
and
unfasten
flare

screw

connecting
ait

gallery
to

injec

tion
nozzle
Remove
air

gallery

EC
14
To
intake

manifold

vaCUl
lm

r

Y

4
9
Gf

T

I
To

air
cleaner

I

Actuated

EC299

Fig
EC
25

Operation
of
air
control
value

Notes

a

Apply
engine
011
to
rews
several

times
during
above

work

b
Be
atreful
not
to

damage
other

parts

3
Unfasten
air

injection
nozzle

from

cylinder
head

applying
engine
oil

to
screwed

portion
several
times

4

Check
air

gallery
and
nozzle
for

fractures
or
leakage
Clean
air

injection

nozzle
with
a
wire
brush

5

At
time
of
installation
hold
air

injection
nozzle

hexagon
head
with

a

wrench
and

tighten
air

gallery
flange

screw
to
a

torque
of
5
0
to
5
9

kg
m

36
to
43
ft
lb

6
Check

cylinder
head
air

injection

nozzle
and
air

gallery
for
leaks
with

engine
running

Air

pump
relief
vslve

Loosen
carburetor
air
cleaner

mounting
sc
ews
and

remove
air

pump
relief
valve

InstallatIon

Install
in
the

reverse
order
of
reo

moval

DISASSEMBLY
AND

ASSEMBLY

Disassembly
of
air
pump

1
Remove
four

pulley
drive
bolts

and
remove

pulley
from
hub

2

Secure
air

pump
drive
hub
in

a

vise

as
shewn
in

Figure
EC

28
and

remove
four
end
cover
bolts

EC540

Fig
EC

38
Install

carbon
shoe

Notes

a

Carbon
shoe
A

is
1
mm
0
039

in

wider
than
B

Do
not
confuse

them

b
If
carbon

shoes
are

exposed
beyond

the
rotor

end
face
remove

carbon

shoes
and
clean
shoe

grooves

Reassemble

carbon
shoes

6

Vane

1
Pack
vane

bearing
with

high

melting
point
grease
MIL
G
3545
A

Esso

ANDOK260
or

equivalent
and

insert

dummy
shaft
into
the

Vane

bearing

STl9900000

EC563

Fig
EC
39
Vane

assembly

2
Install
vane
in

place
on
rotor

using

Dummy
Shaft

STl9900000
as
a

guide

Note
The
vanes

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
50

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
groove

of
shoe
Emission
Control

System

i

111

11

EC123

Fig
EC
40

Installing
shoe

spring

Note
When

instaUing
a
shoe

spring

make
sure
that
the
outward
bend

ing
side

faces
in

shoe
and
that
both

ends

of

spring
face
in
the

wall
of

shoe

groove

Be
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

0
mark

in
rotor

ring
and

tighten

four

screws
to

the

specified

torque

with

Hexagonal
Wrench
ST19810000

Tightening
torque

0
5

to
0
7

kg
m

3
6
to
5
1

ft
lb

5T19810000

EC124

Fig
EC
41

In8talling
rotor

ring

9
Removal
of

dummy
shaft

Carefuny
withdraw

dummy
shaft

from

vane

10

Vane
shaft

Pack

rear

bearing
with

high

melting

point

grease
MIL
G
3545

A

so

ANDOK
260
or

equivalent

Apply
thin

coating
of

grease
to
vane

shaft
and
rotor

ring
and
insert

vane

shaft

into
its

bearing

EC
17
Notes

a

Do
not

apply
an
u
tue
stress

to

vane
shaft
when

inserting

b

If
two
vanes
are
dislocated
when

inserting
vane
shaft

correctly

align

vanes

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
cover
as

sembly

Jl
End
cover

Position
end

cover
in

place

Snugly

tighten
the
bolt
close
to

the
dowel

Then

tighten
four
bolts

to
the

speci

fied

torque

Tightening
torque

0

7
to
0

9

kg
m

5

1

t06
5
ft4b

EC302

Fig
EC
42
Insla
ling
end

cover

12

Pulley

Tighten
four

pulley
securing
bolts

to
the

specified
torque

Tightening
torque

0
7
to
0

9

kg
m

5

lt06
5
ft

lb

INSPECTION

Air

InJection
system
hosas

Check
air

system
hoses
for
loose

connections
cracks
or
deterioration

Retighten
or

replace
if

necessary

Air

ystem
manifold

Check
air

gaUery

pipe
and

injection

nozzles
for
loose
connections
and

cracks

Retighten
or

replace
if
neces

sary

Air

pump

I

Operate
engine
until
it
reaches

normal

operating
temperature

2

Inspect
all
hose
hose
connec

tions
and
air

gallery
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

Disconnect
air
supply
hose
at

check
valve

5

Disconnect
vacuum
hose
from
the

air

control
valve
California

type

only

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

lli
uge
so

that
air
blast
emitted

through
drilled

pipe
plug
will
be

harmlessly

dissipated

7
Install

a
tachometer

on

engine

With

engine
speed
at
2

600

rpm
ob

serve

pressure
produced
at

test

gauge

Air

pressure
should
be
100

mmHg

3

94

inHg
or
more

8
If
air

pressure
does

not
meet

above

specifications
proceed
as
fol

lows

I

Repeat
2
and
3

above

2
Disconnect
air

supply
hose
at

anti
backfire
valve

Plug
air

hose

open

ing
and

screw
with
a

clamp
Repeat

pressure
test

3
With

engine

speed
at
1

500

rpm

close
hole
of
test

gauge
with

finger
If

a

leaking
sound

is
heard
or

leaking
air

is
felt

by
ftnger
at
relief

valve
relief

valve
is

malfunctioning
Relief
valve

should

be

replaced
or

repaired

4

If
air

injection
pump
does
not

meet
minimum

requirement
of

pres

sure
test
it

should
be

replaced

Control
valve

The

following
procedures
are
reo

commended
for

checking
and
or
as

certaining
that
the
various

components

of
the
exhaust
emission
con
Irol

system

are

operating

properly

The

engine
and
all

components

must

be
at
normal

operating
tempera

tures
when
the

tests
are

performed

Prior

to

performing
any
extensive

diag

nosis

of
the
exhaust
control

system
it
Emission
Control

System

must
be
determined
that

the

engine
as

a
unit
is

functioning
properly

Check
valva

Warm

up
engine
thoroughly

2

Disconnect
hose

leading
to
check

valve
from
air

hose
COJUlector

3

Check
hose

opening
for

any
indi

cation
of
exhaust

gas
leaks
Ifleaks
are

detected

replace
check
valve

4

Race
the

engine

lightly
at
about

2
000

cpm
and
then

return
it
to

idling
VisuaDy
check
the
hose
for

any

indication
of
exhaust

gas
leaks
before

the

engine
returns
to

idling

speed
If

leaks
are
detected

replace
check
valve

EC310

Fig
EC
43

Checking
check
valve

Air

pump
raIle
valve

After

completing
inspection
of
air

pump
check
air

pump
relief
valve
in

the

following
steps

J

Disconnect
hoses

leading
to
check

valve
and
air
control

valve
from
air

hose

connector
and

install
blind

cap

to
the

connector

2
With

engine
running
at

about

3
000

rpm
under
no
load

place
your

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

EC311

Fig
EC
44

Checking
air

pump
relief

valve

EC

18
Air
control
valve

C
U
ornla
models

I
Warm

up
engine
thoroughly

2
Before

checking
air
control

valve

check
all
hoses

for
loose
connection

leaks
etc
and

repair
or

correct
if

necessary

3

With

engine
idling
disconnect
the

outlet
side
hose
of

the
air
control

valve
and

place

your
hand
on
the
air

hose
outlet
to
check
for
air
If
no
air
is

felt

replace
the
air

control
valve

4

Pull
vacuum
hose
off
from
air

con
trol
valve
If

discharge
of
air
from

air
hose

stops
the
air
con
trol
valve

is

normaL
If

discharge
is
still
felt

replace

the
valve

Plug
up
the

removed

vacuum
hose

to

stabilize

engine
running

EC312

Fig
EC
45

Checking
air
control
valve

Emarsancy
air
rella
valve

E
A
R
Valve

lCalHornla
models

L
Warm

up
engine
thoroughly

2

Before

checking
air

control
valve

check
all
hoses
for
loose
connection

leaks
etc
and

repair
or
correct
if

necessary

3
Race

engine
approximately

2
000

rpm
under
no
load
Place

your

hand
on
air

outlet
of
E

A
R
valve
to

check
for

presence
of

discharged
air
If

no
air

is
felt

E
A

R
valve
is
normal

4

Disconnect
vacuum
hose
from

B
A

R
valve
as
shown
in

Figure
EC

46

Race

engine
approximately
2
000

rpm
under
no
load
Place

your
hand

on
air
outlet
of
E
A
R
valve
to
check

for

presence
of

discharged
air
If
air
is

felt

E
A
R
valve
is
normaL

5

If
E
A
R

valve
does
not
function

properly
at
above

steps

replace
E
A
R

valve

To

air

pump

I

ET267

Fig
EC
46

Cheeking
E
A
R
volve

Anti
backfire

valve
A
valve

Warm

up
engine

thoroughly

2
Disconnect
hose

from
air

cleaner

and

place
a

finger
near
the
outlet

3
Run

engine
at
about
3

000

rpin

under
no
load
then

quickly
cetum
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
backflre

valve

Fig
EC
47
Checking
anti

backfire
valve
1
t
D

I
Y1

VI
I

ID
4

JO
0

2
E

C
R
control
valve

3

E
C
R

passage

4
Intake
manifold

5

Thermal
vacuum
valve

6
E
C
R
tube

7
Exhaust

manifold
Emission
Control

System

tXHAUST
GAS

RECIRCULATION

CONTROL
SYSTEM

E

G
R

DESCRIPTION

In
the

exhaust

gas
recirculation

system
a

part
of
the
exhaust

gas
is

returned
to
the

combustion
chamber

to
lower
the

spark
flame

temperature

during
combustion
This
results
in
a

reduction

of
the

nitrogen
oxide

con

ten
t

in
the
exhaust

gas

The
exhaust

gas
recirculation

sys

tem
consists

of
an
E
G
R

passage

E
G
R

con
trol
valve
thermal

vacuum

volve
E
G
R

tube
and
hose
A

warn

@
I
ing
system
which
indicates
when
the

E
G
R

control

system
must
be

in

spected
is
also
installed
in

all
620

models

except
those
bound
for

Coli

fornia
and
Canada

When
the
E

G
R
con
trol

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

Open
c1ose

operation
of
the
E
G
R

control
valve

is
controlled

by
the

thermal

vacuum
valve
which

opera
tes

on

carburetor
vacuum
and

engine
cool

ant

temperature

EC349

Fig
EC
4
Exhaust
Gas
Recirculation

system
E
G
R

E
G
R

system
operating
Thermal
Intake
manifold
E
G
R

Remarks

E
G
R

water

temperature
oC
OF
vacuum
valve
vacuum
control
valve

Below
570C
135OF
Close
Close

Non
california

Above

MfT
models

only
Idling

Not
Above
57

to
630C

Open
70

mmHg
Close

actuated
135
to
145OF
76

inHg

California
models

Below

and
N
on
Fullthrollle

f

alifomia

AfT

Above
57
to
6
oC
models

Actua
ted

Open
Above
50

mmHg

Open

135
to
145OF
1
97

inHg

EC
19
OPERATION

Operation
of
E
G
R

system
is
as

shown
below

j

EC231

Thermal

vacuum
valva
o

o

m
Emission

Control

System

0

o

o

o

l

l
@

The
thermal
vacuum
valve

is

mounted
in

the

engine
thermostat

housing
It

detects

engine
coolan
t

tem

perature
by
means
of
a

built
in

bi

metal
and

opensor
closes
the

vacuum

passage
in
the

thermal
vacuum

valve

mt

li

t

00
t

EC232

Fig
EC
54
Thennal

vacuum
valve
To
E

G
R
control
valve

From
carburetor

1

Spring

2
Bi
metal

3

O

ring

E
G
R

warning

system

The

E
G
R

warning
system
install
1

Diaphragm
spring

2

Diaphragm

3
Valve
shaft

4

Valve

5
Valve

Seat

6
Valve
cham
ber

Fig
EC
53
E
G

R
control
value

When
the

vacuum

passage
is

open
the

carburetor
suction

vacuum
is

applied

to
the

diaphragm
of
the
E
G
R

con

trol
valve
to

actuate
the

taper
valve

connected
to
the

diaphragm

theconsiiiictlo

nlie
thermal

vacuum
valve
is

shown
below

ed

independently
of
the

E
G
R

con

trol

system
monitors

the
distance
the

car
has
travelled
and

indicates
when

EC
22
the
E

G
R

control

system
must
be

checked

The
E
G
R

warning
system
consists

of

an
odometer
switch

detector
drive

counter
E

G
R

warning

lamp
and

harnesses

When
the

earn
in
the

odom

eter
switch
connected
to

the

speed

ometer
turns

once
for

each
OAkm
4

mile
the

contact

point
of
the
elec

trica
circuit
closes

allowing
electric

current
to
flow

through
the

magnet

coil
of

the
detector

drive
counter

Thus

energized
the

magnet
coil
ac

Wates

the
latchet
to

turn
the
c
unter

wheel

by
one

pitch
When
the

number

of

counts
reaches
50
000
the
latchet

drops
in

a

groove
provided
on
the

periphery
of

the
counter
wheel
to

activate

the
detector

drive
counter

switch

Then
the

E
G
R

warning

lamp

comes
on

indicating
that
the
E
G
R

control

system
Should
be
checked

The

detector
drive

coun
teT
is

equip

ped
with
an
odometer
which

can
tell

when
to
service

the
E

G
R
contr0
I

system

After

completing

periodic
check

reset
the
odometer
to

zero
by
hand

proceeding
as
follows

1
Remove

grommet
installed
on

the
side

surface
of

detector
drive

counter
unit

2
insert

a
bar

or
a
screwdriver

tip

into
the

hole
from

which

grommet
has

been

removed
and

press
down
knob

provided
in

the
detector
drive
counter

for

resetting

The
E

G
R

warning

lamp
comes

on

under
the

following
circumstances

1
When
the
number
of

counts
has

reached
50
000
In
this

case
the

lamp

indicates
that
E

G
R

control

system

must
be
checked

2
When

operating
starter
motor

Notes

a
It
is

an
indication
of

problem
in

the

E

G
R

warning
lamp
or

problems

in
the

point
or
in
the
harnesses
if

the

lamp
does
not

light
at

50
000

counts

b

The
E

G
R

warning
system
is

mounted

on
all
620
models

except

those

bound
for
California
and

Canada

4
E
G
R

warning
system

EC251

Detector
drive
counter

Detecfor
drive
counter
is
secured

on
the

top
of
R
H

hoodledge
panel
in

engine
room
To

remove
detector
drive

counter
disconnect
w
COJUlector

and

loosen
two
bolts

securing
detector

drive
counter
to
hoodledge

panel

2

E
G
R

warning
lamp

E
G
R

warning
lamp
is
mounted
at

the

top
cen
ter
of
instrument

pad
To

remove
E
G

R

warning
lamp
proceed

as
follows

1
Remove

masking
panel

On
models

equipped
with
radio

remove

warning
lamp
from
under
in

strument

panel

2

E
G
R

warning
lamp
is

a
twist

type

Remove

lamp
and
socket

as
an

assembly
Push
and
twist

lamp
off

can

EC554

Fig
EC
60
Removing
E
G
R

warning

lamp
Emission
Control

System

3
Odometer
switch

Odometer
switch
is
mounted
on
the

back
side
of

speedometer
Cam
in
the

odometer
switch
is
rotated

by
the

speedometer
To

dismount
odometer

switch

proceed
as
follows

I

Dismount
combination
meter
as

sembly

2
Remove
meter
front
cover
and

take
off

clips
and
screws
to

dismount

shadow

plate

3

Loosen
screws

securing
speed

ometer
to

printed
circuit

housing
then

remove

speedometer

4

Remove
two
screws

securing

odomete
switch
to
the

back
side
of

speedometer
and
detach
odometer

switch

EC239

Fig
EC
61

Removing
odometer

switch

InstaUatlon

To
install
reverse
the
removal

pro

cedure

EC24
V

r
CID

1
Detector
drive
counter

2
E
G
R
warning
lamp

3
Speedometer

Fig
EC
59
E
G
R

warning
y
tem

INSPECTION

Checking
E

G
R
control

system
in

its
mounted
conditionS

I

Make
a

thorough
visual
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
running
check

E

G
R

warning
system
for

proper

function
Make
sure
that
E

G
R
warn

ing
lamp
lights
when

ignition
switch
is

turned

to
START

position
starter

mo

tor
runs
If
E
G
R

wanung
lamp
does

not

light
inspect
harnesses
and

con

nectors
or

replace
warning
lamp
Then

turn

ignition
switch
to
ON

position

and

check
the
following
items

I

If
odometer
of
detector
drive

counter
has
not
reached
50
000

counts
make
sure
that
E
G
R

warning

lamp
does
not
light

2
If
odomete
of
detector
drive

counter
has
attained
50
000
counts

make
sure
that
E
G
R

warning
lamp

lights

If

warning
lamp
does
not

light

check
harnesses
connectors
and
de

tector
drive
counter
replace
warning

lamp
or
detector
drive
counter
if

necessary

Notes

Operation
oC
E
G
R

warning
lamp

is
as
Collows

Ignition
Switch
Position
START

Detector
Drive

Counter

E
G
R

Warning
Lamp
ON

b
After

completing
inspection
of

E

G
R

control
system
be

sure
to

reset

odometer
of
detector
drive

counter
to

zero

c
This
item

applies
to
all
620
models

except
those
bound
for
California

and
Canada

3

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

2
When

engine
coolant

tempera

ture
is

high

I
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
a

fmger
on
the

diaphragm
of
E
G
R
control

valve

to
check
for
valve

operation

2
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
thermal
vacuum
valve
to
E
G
R
Emission
Control

System

ON

Below

50
000
counts
Above

50
000
counts

OFF
ON

4
With

engine
running
inspect

E
G
R

control
valve
and
thermal
vacuo

um
valve
for
normal

operation

1
When

engine
coolant

tempera

ture

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

fmger
on
the

diaphragm
of

E
G
R
control
valve
to

check
for
valve

operation

EC253

Fig
EC
62

Checking
E
G
R
control
valve

control
valve

Increase

engine
speed
from

idling
to

3
000
to
3

500

rpm

Make
su
re
that
thermal
vacu
um

valve
is

open
and
that

carburetor

vacuum
is

present
at
the
end

E

G
R
control

valve
side
of

vacu

um
hose

If
vacuum
is
weak
or

not

present
at

all

replace
thermal
vacuum
valve
If

vacuum
is

present
replace
E
G

R

control
valve

EC
25
EC254

Fig
EC

63

Checking
lhermal

vacuum
valve

If

any
difficulty
is
encountered
in

judging
the
condition
of

any

compo

nent

during
above

inspection
check

the

questionable
component
independ

ently
as

follows

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

la

ET152

Fig
EC
64

Checking
E
G
R

control

ualue

2

Visually
check
E
G
R

control

valve
for

damage
wrinkle
or
defonna

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