air condition DATSUN 210 1979 Owner's Manual

Condition

Loss
of

water

Poor
circulation

Corrosion

Overheating

Over

cooling
Cooling
System

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Probable
cause

Damaged
radiator
seams

Leaks

at
heater
connections

or
plugs

Leak
at

water

temperature
gauge

Loose

joints

Damaged
cylinder
head

gasket

Cracked

cylinder
block

Cracked

cylinder
head

Loose

cylinder
head
bolts

Restriction
in

system

Insufficient
coolant

Inoperative
water

pump

Loose
fan
belt

Inoperative
thermostat

Excessive

impurity
in
water

Infrequent
flushing
and

draining
of

system

Inoperative
thermostat

Radiator
fin
choked
with
mud
chaff
etc

Incorrect

ignition
and
valve

timing

Dirty
oil
and

sludge
in

engine

Inoperative
water

pump

Inoperative
torque
coupling
or

tem

coupling

Loose
fan
belt

Restricted
radiator

Inaccurate

temperature
gauge

Impurity
in
water

Inoperative
thermostat

Inaccurate

temperature
gauge

CO
7
Corrective
action

Repair

Repair

Tighten

Tighten

Replace

Check

engine
oil
for

contamination
and
reml

as

necessary

Replace

Check

engine
oil
in

crankcase
for

mixing

with
water

by
pulling
oil

level

gauge

Replace

Tighten

Check
hoses
for

crimps
and
clear
the

system

of
rust
and

sludge
by
flushing
radiator

Replenish

Replace

Adjust

Replace

Use
soft
clean
water
rain

water
is
satis

factory

Cooling
system
should
be
drained
and
flush

ed

thoroughly
at
least
twice
a

year

Permanent
antifreeze

Ethylene
glycol
base

can
be

used

throughout
the

seasons
of
the

year
and

change

periodically
at

intervals

recommended

Replace

Clean
out
air

passage
thoroughly
by
using
air

pressure
from

engine
side
of
radiator

Adjust

Refill

Replace

Replace

Adjust

Flush

radiator

Replace

Use
soft
dean
water

Replace

Replace

Engine
Fuel

AUTOMATIC
TEMPERATURE
COtirROL
A
T

C

AIR
CLEANER

DESCRIPTION

U

S
A

mode
18

ExC
FU

model

I

C1J
Cana
ia
and
FU

models

I
Air

relief
valve
Non

alifornia

models

2

Air
hole
for
T
C

S

3
P

C
V

mter

4
Air

hole
for
A
B

valve
5
Idle

compensator

6
Outlet
for
C
A

C
valve

California
model

7

Temperature
seIl50r

8

Heat
control
valVe

EF415A

Fig
EF
l
A
T
C

Air
Cleaner
U
S
A
model

except
FU
model
8
3

1

Air
hole

for
T

C
S

2

Air
induction
valve
and

ftIter

3
P

C
V

mtet
Air

hole
for
A
B

valve

Idle

compen
ator

Temperature
sensor

Heat
control
valve

EF041A

Fig
EF
2
A
T
C
Air
Cleaner
Canado
ond
FUmodel

The

automatic

temperature
control
system
of

the
air

cleaner
is

control
ed

by
the
inlet
air

temperature
and
the

load
condition
of
the

engine
The
inlet
air

temperature
is
detected

by
th

sensor
and
the

vacuum
motor
is

actu

ated

by
the

engine
intake
vacuum
OPERATION

Engine
Under
hood
air

temperature
Sensor
vacuum
at

vacuum
motor

side
Air

con
trol
valve

operation
Sensor

operation

Below
380e

IOO
F
Below
40

mmHg

1
57

inHg
Open
cold
air

AI4
A15
Above
160

mmHg

6
30

inHg
Closed

Closed
hot

air

38
to

S40C

100

to
l290F
Partially
open

cold
air
hot
air
Partially
open

Above
550e

1310F
Open
cold
air

Open

HOT
AIR

OPERATION

When

the

engine
intake
air

tempera

ture
is

low
the

sensor
air
bleed
valve

remains
in

the
closed

position
and

establishes
vacuum

passage
betw

n
the
intake
manifold
and

vacuum

motor
With

this
condition
the
vacu

um
at

the
intake
manifold
side

actuates
the
air

control
valve
attached
to
the

vacuum
motor

diaphragm
to

introduce
hot
air
into
the
air
cleaner

through
the
hot
air

duct
on
the
ex

haust
manifold

EF
2

TEMPERATURE
SENSOR

Removal

I

Using
pliers
flatten

clip
con

necting
vacuum

hose
to

sensor
vacuum

tube

1

Pipe

2
Catch

3
Fixed
with

adhesive

4
Hose

5
Tab

6

Clip

7
Gasket

EC019

Fig
EF
7

Removing
Seruor

2
Disconnect
hose
from

sensor

3
Take
off

clip
from
sensor
vacuum

tube
and
dismount
sensor

body
from

air
cleaner

Note

The

gasket
between

sensor
and

air

cleaner
is
bonded
to

the
air

cleaner

side
and

should
not

be

removed

Installation

Mount
sensor
on
the

specified

position

2

Insert

clip
into

vacuum
tube
of

sensor
After

installing
each
vacuum

hose

secure
hose
with
the

clip

Note
Be

sure
to
install
vacUl
11n

hose

correctly
Correct

position
is
R
H

side
to

Ntisan

mark
at
the

top

face
of
sensor
for
intake
manifold

L

H
side
for

Deuum
motor

VACUUM

MOTOR

1

Remove

screws

securing
vacuum

motor

to
air
cleaner

2

Disconnect

valve
shaft

attached

to

vacuum
motor

diaphragm
from
air

control
valve

and

remove

vacuum

motor

assembly
from
air

cleaner

3
To
install

reverse
the

removal

procedures
Engine
Fuel

Fig
EF

8
Removing
Vacuum
Motor

INSPECTION

AIR

CLEANER
FILTER

Viscous

paper

type
air

cleaner
filter

does

o
ot

rt

quire
any
cleaning
opera

tion

until
it

is

replaced
periodically

Brushing
or

blasting
operation
will

cause

clogging
and
result

in
enrich

ment

of
carburetor
mixture

and

should
never
be

conducted
For
reo

placement
interval
of
air

cleaner
filter

refer
to

Maintenance

Schedule

AUTOMATIC

TEMPERATURE

CONTROL
SYSTEM

Engine
failures

resulting
from
a

malfunctioning
A
T
C

system
are

manifest

during
cold
weather

opera

tion
Such
failures

include

Engine
stall
or
hesitation

Increase
in
fuel

consumption

Lack
of

power

If
these

phenomena
should

occur

check

A
T
e

system
as

described
in

the

following
before

carrying
out

inspection
of

carburetor

I
Check
that

vacuum
hoses
are

se

l

urely
connected
in
correct

position

2

Check
each
hose

for
cracks
or

distortion

3

Check
A
T

C

system
for

proper

function
as

follo
ys
Confirm
that

engine
is

cold
before

starting
test

With

engine
topped
disconnect

fresh
air

duct
if
so

equipped

Place
a
mirror
at
the
end

of
air

cleaner
inlet

pipe
as
shown
and

check

to
see
if
air
control
valve

is
in
correct

position

EF
4
Fig
EF
9

Inspecting
Valve
Po

man

Air
control
valve
is

in
correct

posi

tion
if
its
cold
air
inlet

is

open
and

hot

air
inlet
is

closed

4
Start

engine
and

keep
idling

Immediately
after

engine

starting

check
air
control

valve
for

correct

position
as
described
above
In

this

case
correct

position
of
air
control

valve
is

the

reverse
of

step
3

under

hood
air
inlet
is
closed

and
hot
air

inlet
is

open

S

Check
that
air
control
valve

grad

ually
opens
to

cold
air

inlet
side

as

engine
warms

up
When

environmental

temperature
around

temperature
sen

sor
is
low

spend
more
time

for

engine

warming
up
operation
to
facilitate

smooth

operation
of
air
control

valve

If
the
above

test
reveals

any
prob

lem
in
the

opera
ion
of
air
control

valve

carry
out
the

following
test

VACUUM
MOTOR

I
With

engine
stopped
confirm

that

cold
air
inlet
is

open
and

hot
air

inlet
is

c1
Sed

If
not

check
air
control
valve
link

age
for

proper
operation

2

DiscoJln
ct
ac
um

motor
inlet

vacuum
hose

and
connect

another

hose
to
the

inlet
to

apply
vacuum
to

vacuum
motor

Vacuum
can

be

appli
d

by
breathing
in

tile
hos
e
end

as

shown
Then

confirm
that

the
air

control
valve

moves

3
With
hot
air
inlet
in

open
posi

tion
as

described
in

step
2

above

pinch
vacuum
hose
with

fingers
and

cut
off
air
from

vacuum
hose
In

this

condition

check
that
air
control

valve

maintains
the

condition
described
in

step
2

for
more
than

30
seconds

and

that
hot

air
inlet

is

open
If

diaphragm

spring
actuates

the
air
control
valve

by

DESCRIPTION

The

carburetors
are

of
downdraft

two

barrel

type

designed
to
increase

ppwe
r
a
fu
l
eC

l
Il
Y
t

3
ell
a

to

reduce

exhaust

gas
emissions

These
carburetors

present
several

distinct
features
of

importance
to

car

owner

A

summary
of

features
is
as
fol

lows

1

Secondary
throttle
valve
is

oper

ated

by
throttle
lever

High
power
and

good
acceleration
are

gained
with
com

bination
of
the

auxiliary
valve

2

Accelerating

pump
provide
ex

cellent
acceleration

3
Power
valve
mechanism
is

a
vacuo

urn
actuated

boost

type
and

improves

high
speed
driving

4

The
throttle

opener
control

sys

tem

Except
FU
model

incorporates
a

servo

diaphragm
which

helps
open
the

throttle
valve
at

a

decreasing
speed
so

as
to

reduce

hydrocarbon
emissions

to

a
minimum

5
An
anti
d

eseling
solenoid

valve
is

installed
to

prevent
dieseling
When

ignition
key
is

turned
off
the

fuel

passage
involved
in
the
ow

system
is

closed
and
the
fuel

supply
is
shut

down

completely

The
solenoid
valve
also

serves
as
an

actuator
of
the
fuel

shut
off

system
on

the

FU
model

6
In
the
choke
mechanism
an

elec

trie
automatic

choke
is
used

to
auto

maticaDy
control
chok
valve

opera

tion

during
engin
war

up

7

The
carburetor
comes

equipped

with
dash

pot
which
ensures
smooth

deceleration
without

engine
stall
under

aU

operating
conditions

STRUCTURE
AND

OPERATION

These
carburetors
consist
of
a

main

system
for
normal

running
a
slow

system
for

idling
and

an

accelerating

and

power
mechanisIll

Some

emission
control
devices

are

added
E
ngine
Fuel

CARBURETOR

I

J

1

Primary
main

jet

2
Idle

adjust
screw

3
hUe
nozzle

4

By
pass
hole

5

Primary
throttle
valve

6

Primary
slow

jet

7

ptug

8

Primary
5l

w
air
bleed

9

Primary
main
air
bleed
10

Primary
air
vent

pipe

11

Primuy
main

nozzle

12

Choke
valve

13

Primary
small

venturi

14

Secondary
small

venturi

15

Secondary
air
vent

pipe

16

Secondary
main

nozzle

17

Secondary
main
air
bleed

18

Secondary
slow

air
bleed

1
Oloke
valve

2

Primary
air
vent

pipe

3
Prima
y
main
nozzle

4

Primary
slow

jet
19

Plug

20

Secondary
slow

jet

21

Needte

22
Fuel
fLlter

23

Secondary
tIuottle

valve

24

Auxiliary
valve

25

Secondary
main

jet

Note
Do
not
remo
the

parts
inarbd

with
anuteriak

EF416A

Fig
EF
17
Carburetor

PRIMARY

SYSTEM

PrlinarJ
main

sJstam

The
fUel

flowing
out
of
the

passages

at
bottom
of

float
chamber

passes

through
the

primary
main

jet
and
is

mixed
with
air

coming
from
main
air

bleed
The

gas
mixture
is

pulled
out

into
the

venturi

through
the
main

nozzle

When

throttle
valve
is
wide

open

and

engine
require
dense
mixture

gas

power
valve

opens
and
fuel
also
flows

into
main

system

EF044A

Fig
EF
18

PtJrlially

Loading

EF
8

I

Secondary
slow
air

bleed

2

Secondary
main
air
bleed

3

Secondary
main
nozzle

4

Primary
main
nozzle

5

Primary
main

air
bleed

6

Primary
slow
air
bleed

7

Primary
slow

jet

8

Primary
main

jet

9
Idle
nozzle

10
Primary
throttle
valve

II

Auxiliary
valve

12
Seco
dary
throttle
valve

13

Secondary
main

jet

14

Counterweight

IS

Secondary
slow

jet

EF419A

Fig
EF
24
At
Full

Open
High
Speed
Engine
Fuel

Secondary
slow

system

Step
system

The
construction
of
this

system

corresponds
to

the

idling
and
slow

system
of
the

primary
system

This

system
aims

at
the

power

filling
up
of
the

gap
when

fuel

supply

is
transferred
from

the

primary
system

to
the

secondary
system
The

stepport

is
located

near
the

auxiliary
valve
in
its

fully
closed
state

ANTI

DIESELING
SYSTEM

The

carburetor
is

equipped
with
an

anti
liese1i

lg
solenoid

valye

As
the

ignition
switch
is

turned
off

the
valve
is

brought
into

operation

shutting
off
the

supply
of

fuel
to

the

slow
circuit

The

following
figure
shows
a
see

tional
view

of
this

control

An

ti
dies

eling
solenoid
valve

Ignition
switch
OFF

ON

t

L
li

FLOAT
SYSTEM

There
is

only
one
float
chamber

while
two
carburetor

systems

primary

and

secondary
are

provided

Fuel
fed
from
the
fuel

pump
flows

through
the
filter
and
needle
valve
into

the
float

chamber
A
constant
fuel

level
is
maintained

by
the

float
and

needle
valve

Because
of

the
inner
air

vent

type

float

chamber
ventilation
fuel
con

sumption
is

not
affected

by
dirt
ac

cumulated
in

the
air
cleaner
Ignition
switch

Q

1

T
Battery

niT

EC
3

Fig
EF
25

Anti
dieseling
Solenoid
Valve

The
needle
valve
includes

special

hard

steel
ball
and
wiD

not
wear
for
all

its

considerably

long
use

Besides
the
insertion
of

a

spring

will

prevent
the

flooding
at

rough
road

running

THROTTLE
OPENER

CONTROL
SYSTEM

T
O
C
S

Except
FU

model

The
function

of
the
throttle

opener

is
to

open
the

throttle
valve
of
the

carburetor

slightly
while
the
car
is
in

EF
10
deceleration

During
deceleration

the

manifold
vacuum
rises
and

the

quan

tity
of
mixture
in
the

engine
is

not

suffICient
for
normal

combustion
to

continue

4
consequently
a

great

amount
of

unburned
HC
is
emitted

Carburetors

equipped
with

the

throttle

opener
supply
the

engine
with

an

adequate
charge
of

combustible

mixture
to
maintain

proper
combus

tion

during
deceleration

resulting
in
a

dramatic
reduction
in
HC

emission

The

system
for
the

manual
trans

mission
model
consists
of

servo
dia

phragm
vlicuum

control
valve
throttle

opener
solenoid
valve

spee
l

detecting

switch
and

amplifier
On

the
auto

matic

transmission
model
an
inhibitor

and
inhibitor

relay
are
used
in

place
of

speed

detecting
switch
and

amplifier

on
the
manual
transmission

model
An

altitude

corrector
fitted
to
vacuum

control
valve

serves
to

automatically

regulate
the

operating
pressure
in

the

system
with

variation
of

atmospheric

pressure

T
o
C
S
n

operatIon

At
the

moment

when
the

manifold

vacuum
increases
as

occurs

upon
de

celeration

the
vacuum

control
valve

opens
to
transfer

the
manifold

vacuum

to
the
servo

diaphragm
chamber
and

the
throttle
valve
of
the

carburetor

opens

slightly

Under
this

condition
a

proper

amount

of
fresh
air

is
sucked

into
the

combustion
chamber
As
the
result

complete
combustion
of
fuel
is

as

sisted

by
this
additional
air

and
the

amount

of
H
C

contained
in

exhaust

gases
is

dramatically
reduced

Throttle

Clpener
sol
nold

valve

operation

Manual

transmission
models

The
throttle

opener
solenoid
valve

is
controlled

by
a

speed

detecting

switch
which
is

actuated

by
the

speed

ometer
needle

As
the

car

sp
ed
falls
below
16

km
h
10
MPH

this
switch
is
acti

vated

producing
a

signal

The

signal
is

led
to
the

amplifier
so

that
the

signal
can
be

amplified
to

a

degree

large
enough
to
actuate
the

ELECTRIC
AUTOMATIC

CHOKE

An
electric
heater
warms
a
bi
metal

interconnected
to
the
choke
valve
and

controls
the

position
of
c
oke

valve

and
throttle
valve
in
accordance

with

the

time

elapsed
the
warm

up
condi

tion
of
the

engine
and
the
outside

ambient

temperature

Electric
heater

The
electric

heater
is
made

up
of

a

semiconductor
and

installed
in

the

automatic
choke
cover
in

the

body

2
Bi
metal

Electric
current

flows

through
the

heater

as
the

engine
starts
and
warms

the
bi
metal
The

deflection
of
the

bi

metal
is

transmitted
to
the
choke

valve

through
the

choke
valve
lever

3

Fast
idle
cam

The

fast
idle

cam
determines
the

opening
of
the

throttle
valve

SQ
that

the

proper
amount

of
mixture

cor

responding
to
the

opening
of
the

choke
valve
will
be

obtained
The

opening
of
the

choke
valve
is
de

pendent

upon
the
warm

up
condition

of

the

engine

4
Choke
unloader

When

accelerating
the

engine
during

the

warm

up
period
that
is

before
the

choke
valve

opens
sufficiently
this

unloader
forces
the

choke
valve

open
a

little

so
as
to
obtain
an

adequate

air
fuel
mixture

S

Vacuum
break

diaphragm

After
the

engine
has
been
started

by
cranking
this

diaphragm
forces
the

choke
valve

open
to
the

predetermined

extent
so
as
to

provide
the

proper

air
fuel
ratio

A
two

stage
acting
type
vacuum

diaphragm
is

employed

6
Si
metal

case
index
mark

The
bi
metal
case
index
mark
is

used
for

selling
the
moment
of
the

bi
metal
which
controls
the
air

fuel

mixture
ratio

required
for

starting
Engine
Fuel

r
m

2

3

4

5

6
r
3

1

@
@
Alternator
L

terminal

Automatic

choke

relay

Automatic
choke

cover

P
T
C
heater

Bi

metaJ

spring

Choke
valve

Fig
EF
31
Electric
Automatic
Choke

l
eater
EF045A

l

A

Higher
ambient
temperature

Manifold

vacuum
Clearance
B

B
Lower
ambient

temperature
Clearance

Manifold

vacuum
1
Hi
metal

2
P
T
e
heater

3
Thermostat
cover

4
Vacuum

diaphragm

5
Fast
idle

earn

6
Bi
metal
cover

index
mark

7
Choke
shaft
lever

8
Choke
valve

9
Unloader

tang

10
Throttle
valve

11
Fast

idle

adjusting
screw

EF243

t

Diaphragm

2

Spring
I

3

Spring
11

4
Rod

5
Choke
valve

6
Plate

@
7
Bi
metal

EF884

Fig
EF

32
Electric
Automatic
Choke

EF

13

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