check engine DATSUN PICK-UP 1977 Workshop Manual

The

pump
shaft
is

supported
by
a

double
row

of
ball

bearings

press
fit
in

an
aluminum
die
cast

pump
body
The

bearings
are

permanently
lubricated

and
sealed

to

prevent
loss
of
lubricant

and

entry
of

dirt

The

pump
is

provided
with
an

impeller
which
turns
on
a
steel

shaft

The

steel
shaft
rotates

together
with

the

torque

coupling
wheeL
The
volute

chamber
is
built
in
the

engine
front

cover

assembly

The
inlet
of
the

pump
is

connected

to

the
radiator
s
lower
tank

by
a
hose

i

o

CQ047

Fig
CO
2
Water

pump
and

engine

front
cover

REMOVAL
AND

INSTALLATION

Removal

in
to
a
clean

con

assembly

I

CQ048

Fig
CO
3
Removing
water

pump

Installation

1
Be

sure
to
clean
the

gasket
sur

faces
in
contact
with

pump
and
front

cover

Always
use
new

gaskets
when

installing

pump
assembly
Be
sure
to

tighten
bolts
Cooling
System

Tightening

torque

0
4
to
0
5

kg
m

3
0
to
3
6
ft
lb

2

Fill

cooling
system
and
check
for

leaks
at

pump

3

Install
fan
blade
and

tighten
at

taching
bolts

securely
Install
belt
and

adjust
for

specified
tension

4

Operate
the

engine
at
fast

idling

and
recheck
for
leaks

5
Install
fan
shrouds

Note
Ensure
that
clearance
between

shroud
and
Can
is

even
at

any

place

DISASSEMBLY

Water

pump
is

made
of
aluminum

and
its

bearing
outer
race
is
of
a

press

fit

type
For
this

reason
water

pump

should
not
be
disassembled

INSPECTION
AND

ADJUSTMENT

Inspection

Inspect
pump
assembly
for
the

fol

lowing
conditions
and

replace
if
nee

essary

1

Badly
rusted
or
corroded

body
as

sembly
and

vane

2

Excessive
end

play
or

roughness
of

bearings
in

operation

3
Reduced

cooling
efficiency
due
to

deteriorated
silicone
oil

4
Oil

leakage
in

torque
coupling
Adjustment

Fan

belt
should
be

properly
ad

justed
at
all
times
A

tight
belt
causes

wear
of

alternator
and
water

pump

bearings
A
loose
belt

brings
about

improper
cooling
fan
water

pump

and
alternator

operation

Check
the
belt
slack
between
alter

nator
and
fan

pulley
by
force
of
10

kg

22
lb

Slackness
of
fan
belt

8
to
12

mm

0
31
to
0
47
in

If

adjustment
is

necessary
loosen

bolt

retaining
alternator

adjusting
bar

to
alternator
Move

alternator
toward

or

away
from

engine
until
the
correct

tension
is
obtained

TORQUE
COUPLING

Except
air

conditioner

equipped

models

The

torque
coupling
keeps
the
fan

speed
at
2
500

rpm
rated
or
below

to

conserve
horsepower
at

high
engine

speed
It
also

helps
reduce
fan
noise
to

a
minimum

during
high
speed
opera

tion

This
unit
is
filled
with
a

special

silicone
oil
used
as
a

fluid

coupling

which
controls
the

fan

speed
Silicone

oil

can
not
be

replenished

1

Torque
coupling
wheel

2

Torque
coupling
cover

3

Torque
coupling
bearing

4
Pulley

5
Water

pump

C0060

Fig
CO
4
Sectional
view
of

torque
coupling
and
water

pump

00
3

Conventional

COUplin9

WATER
PUMP
SPEED

F

Z

Tern

coupling

WATER
PUMP

SPEED

C0029

Fig
CO
6
Characteristic

of

Tern
coupling

INSPECTION

Check
Tem

coupling
for
oil

leakage

or
bend
of
bimetal

If
the
above

symptoms
are
found

replace
it
with

a
new
one
as
an

assembly

THERMOSTAT

A
wax

pellet
type
thermostat
is

mounted
in
the
thermostat

housing
at

the

cylinder
head
water
outlet

The
function
of
the
thermostat
is

to
control
the

flow
of
coolant
facili

tating
fast

engine
warm

up
and

regu

lating
coolant

temperature
The
ther

mostat
is

designed
to

open
and
close
at

predetermined
temperatures
and
if

not

operating
properly
should
be

re

moved
and
tested
as
described
below

REMOVAL
AND

INSTALLATION

I

Drain
coolant

partially

2
Disconnect

upper
radiator
hose
at

water
outlet

3

Remove
bolts

and
remove
water

outlet

gasket
and
thermostat
from

thermostat
housing

Fig
CO
7

Removing
therm06t
t
Cooling
System

4

After
checking
thermostat
re

install
with

a
new

housing
gasket
in

place

5
Reinstall
water

outlet

6

Replenish
coolant
and
check
for

leaks

INSPECTION

A

sticking
thermostat
will

prevent

the

cooling
system
from

functioning

properly
If
the
thermostat
sticks
in

the

open
position
the

engine
warms

up
very
slowly
If
the
thermostat

sticks
in

the
closed

position
over

heating
will
result
Therefore
the
ther
mostat
should
be

inspected
to

make

sure
that
it
is
in

good
condition

1
Measure
coolant
temperature

when
thermostat
valve
starts
to

open

2
Measure
the
maximum
lift

of

thermostat
valve

Fig
CO
S

Impecting
therm06t
t

Temperate
Frigid
Tropical

type

type
iype

Valve

opening

80
5
to
83
5
86
5
to
89
5
75

to
78

temperature

177
to
183
187
to
193

167
to
172

oC
OF

Maximum

valve
lift
8
95
8
1
00
8
90

mm
oC

in
F
0
31
203

0
31
212
0
31

194

If
thermostat
does
not

operate
at

the
above

specified

temperature
it

must
be

replaced
because
it
cannot
be

repaired

RADIATOR

The
radiator
is

a
conventional
down

flow

type
having

top
and

bottom

tanks
to

distribute
the
coolant
flow

uniformly
through
the
vertical
tube
of

radiator
core

The

radiator
filler

cap
is

designed
to

maintain
a

pre
set

pressure
0
9

kg
cm2
13

psi
above

atmospheric

pressure

The
relief
valve

consisting
of

a

blow
off

valve
and
a

vacuum
valve

helps
to

prevent
the
coolant
from

boiling
by
giving

pressure
to
it
How

ever
when

the

pressure
is
reduced

below

atmospheric

pressure
the

vacu

um
valve
allows
air

to
re
enter

the

radiator

preventing
the
formation
of
a

vacuum
in
the

cooling
system

CO
5
On
models

equipped
with
auto

matic
transmission

the
oil
cooler
is

combined
with
the

radiator
to
cool

transmission
fluid

REMOVAL
AND

INSTALLATION

Drain
coolant
into
a
clean
con

tainer

2

Disconnect
radiator

upper
and

lower
hoses
On
models
with
auto

matic
transmissions
disconnect
cooler

inlet
and
outlet
lines
from
radiator

3

Remove
fan
shroud
retaining

bolts
and

remove
fan
shroud

4

Remove
front

grille

5

Remove
radiator
retaining
bolts

and
then

remove
radiator

upward

6
Install
radiator
in
the
reverse
se

quence
of
removal
Note
the
fol

lowing

I
Insert
hoses
in

their

positions

until

they
bottom

2
Ensure
that
arrow
marks
on

hoses
are

clearly
visible
from

upper

Condition

Loss

of
water

Poor
circulation

Corrosion

Overheating

Overcooling
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

Loose
fan
belt

Restricted
radiator

Inaccurate

temperature
gauge

Impurity
in

water

Inoperative
thermostat

Inaccurate

temperature
gauge

CO
7
Corrective
action

Repair

Repair

Tigh
ten

Tighten

Replace

Check

engine
oil
for
contamination
and
refill

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

flushed

periodically
Permanent
anti
freeze

Ethylene
glycol
base
can
be

used

through

out
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

Adjust

Flush
radiator

Replace

Use
soft
clean
water

Replace

Replace

r

AIR
CLEANER

1
Loosen

bolts

securing
air
cleaner

to
air
cleaner
bracket

2
Loosen
air

cleaner
lock
bolt
and

remove
air

cleaner
from
carburetor

Disconnect
the

following
hoses
when

dismounting
air

cleaner

Under
hood
air
inlet

hose

Hot
air
inlet

hose

Vacuum

hose
Sensor
to
intake

manifold

Vacuum
hose
Sensor
to
vacuum

motor

Vacuum
hose

Idle

compensator
to

intake
manifold

Hose
Air

pump
to
air
cleaner

Hose
AB
valve

to
air
cleaner

Hose
Carburetor
to
air

cleaner

Blow

by
hose
Air

cleaner
to

rocker

cover

Hose
Air

control
vaive
to
air

cleaner
California

models

only

3
To

install

reverse
the
removal

procedure

INSPECTION

1
AIR
CLEANER

ELEMENT

Viscous

paper
type
air
cleaner

ele

ment
does
not

require
any
cleaning

operation
until
it

is

replaced
periodi

cally
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
ele

ment
refer
to
Maintenance
Sched

ule

2
HOT

AIR

CONTROL
SYSTEM

In

warm
weather
it
is

difficult
to

find

out
malfunction
of
hot
air
control

system
In

cold
wea
thee

however

malfunction
of
air
control
valve

due
to

disconnection
or

deterioration
of

vacu

um

hose
between
intake
manifold
and

vacuum
motor
and

insufficient
dura

bility
of
air
control
valve

will
cause

insufficient
automatic
control

opera

tion

for
intake
air
and

result
in

engine

disorder

including

I

Stall

or
hesitation
of

engine

oper

ation

2

Increase
in

fuel

consumption

3

uck
of

power
Engine
Fuel

These

phenomena
reveal
malfunc

tion
of
hot
air
control

system
If
these

phenomena
should
occur
check
hot

air
control

system
as

described
in
the

following
before

carrying
out

inspec

tion

of
carburetor

2
1
Vacuum

hose

Intake
manifold
to
3

way
connec

tor
3

way
connector
to

temperature

sensor
3

way
connector
to

idle
com

pensator
temperature
sensor
to
vacu

um

motor

I

Check
that

vacuum
hoses
are

se

curely
connected
in

correct

postion

2

Check
each
hose
for

cracks
or

distortion

hose

clip
for

condition

Note

Vacuum
hose

position
R
H

side
of
Nissan

mark
on
the

top
of

sensor
is
for

intake
manifold
L
U

side
of

the
mark

is
for

vacuum

motor

2
2
Vacuum

motor

I

With

engine
stopped
disconnect

fresh
air

duct

Place
a
mirror

at
the
end
of
air

cleaner
inlet

pipe
as
shown
and

check

to

see
if
air

con
trol
valve

is
in

correct

position

EF213

Fig
EF
11

Inspecting
valve

position

Air

control
valve
is
in

correct

posi

tion
if
its
under
hood
air

inlet
is

open

and
hot
air
inlet
is

closed
Check
air

control
valve

linkage
for

condition

2

Disconnect

vacuum
motor
inlet

vacuum
hose
and
connect

another

hose
to
the
inlet
to

apply
vacuum
to

vacuum
motor
Vacuum
can
be

ap

plied
by
breathing
in
the

hose
end

as

shown

Place
a
mirror

at
the

end
of
air

cleaner
inlet

pipe
and

check
to

see
if

air

control
valve

is
in
correct

position

EF
6
EF217

Fig
EF
12

Inspecting
valve

position

Correct

position
of
air

control
valve

is

the
reverse
of

paragraph
J
above
Air

control
valve
is
in
correct

position
if

under
hood
air
inlet
is

closed
and
hot

air

inlet
is

open

3
With

hot
air

inlet
in

open
posi

tion

as
described
in

paragraph
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
de

scribed
in

step
2

for
more
than
30

seconds
and
that
hot
air

inlet
is

open

If

diaphragm
spring
actuates
the
air

control
valve

by
its

spring
force
to

open
under
hood
air
inlet

within
30

seconds

replace
vacuum
motor
as
an

assembly
since
this

may
be

resulted

from

air
leak
at
vacuum
motor
dia

phragm

2
3
Temperature
ensor

Check

temperature
sensor
for
func

tion

by

proceeding
as
follows
Be

sure

to

keep
engine
cold
before

starting

test

I

With

engine
off

check
air

control

valve
for
condition
In

this
case
under

hood
air

inlet
is

open
Use
a
mirror

for

inspection
as
2
2
1

above

2

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
2
2
I

under

hood
air

inlet
is

closed
and
hot

air

inlet
is

open

3
Check
that
air
control
valve

grad

ually
opens
to
under
hood
air

inlet

side
as

engine
warms

up
When
en

vironmental

temperature
around
tern

perature
sensor
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

operation
of
air

control

valve

carry
out
the

following
test

4
Remove
air

cleaner
cover
Set

temperature
sensing
element
of
ther

mistor
or

thermometer
to
a

position

where

temperature
around
sensor
can

be

measured
In

this
case
fIx

wiring
of

thermistor
or

thermometer
on
the

bottom

surface
of
air

cleaner
with

adhesive

tape
in

such
a
manner
that

the

set

position
of

temperature
sensing

DESCRIPTION

OPERATION

DESCRIPTION

The
idle

compensator
is

basically
a

thermostatic
valve

which
functions
to

introduce
the
air

directly
from
the
air

cleaner
to
the

intake
manifold
to

compensate
for
abnormal
enrichment

of
mixture
in

high
idle

temperature

The
bi
metal

attached
to
the
idle

compensator
detects

the

temperature

of
intake
air
and

opens
or
closes
the

valve
Two

idle

compensators
having

different

temperature
characteristics

are

installed
one

opens
at
an
intake
air

temperature
of

60
to
700C
140
to

l580F

and
the
other
at
70

to
900C

158
to
1940F

OPERATION

The
construction
of
the
idle

com

pensator
is

shown
in
the

following
Engine
Fuel

element
will
not
be
affected

by
air

flow

Then
install
air
cleaner
cover

Fig
EF
13

Checking
temperature

sensor

IDLE
COMPENSATOR

CONTENTS
5

Carry
out
test
as
described
in

steps
I
2
and
3
above
When
air

control
valve

begins
to

open
to
under

hood
air
inlet
side
several
minutes

after

engine
starting
read
the

indica

tion

of
thermistor
or

thermometer
If

reading
falls
within
the

working
tern

perature

range
of

temperature
sensor

the
sensor
is

normal
If

reading
ex

ceeds
the

range

replace
the

sensor

with
new
one

Note
Before

replacing
temperature

sensor
check

idle

compensator
as

described
in

Idle

compensator

EF
7

EF
7
REMOVAL
AND
INSTALLATION

INSPECTION
EF

B

EF

8

q

EF222
1

Orifice

2
Bi
metal

3
Rubber
valve

Fig
EF

14
Structure

of
idle

compensator

Bi

metal
Intake
air

temperature

No

1
Below
600C
1400F

60
to
70
C

140
to
l580F

Above
700C

158
OF

Below
700C

1580F

70
to
900C

158
to
1940F

Above
900C
1940F
No
2

EF
7
The
idle

compensator

operates
in

response
to
the

under
hood
air

temper

ature

as
shown
below

Idle

compensator
operation

Fully
closed

Close
to

open

Fully

open

Fully
closed

Close
to

open

Fully

open

Engine
Fuel

REMOVAL
AND
INSTALLATION

Remove
air
cleaner

cover

2
Remove
hose

connecting
idle

compensator
and
3

way
connector

3
Loosen
screws

securing
idle
com

pensator
to
air

cleaner
then
remove

idle

compensator

Notes

a
When

removing
idle

compensator

remove

gasket
and

plate

b
When

removing
screw

securing
idle

compensator
to
air

cleaner
be
care

ful
not
to

miss
the
saew

4
To
install
reverse
the
removal

procedure

INSPECTION

I
Check

tha
t
valve
IS
m
closed

position
when
bi

metal

temperature
is

lower

than

operating

temperature
To

check
breathe
air
into

tube
or
suck

DESCRIPTION

The
fuel
fJlter
is

a

cartridge

type
It

uses
a

paper
element
which
can
be

checked
for
condition
from
the
out

side
EF718

Fig
EF
15
Location

of
idle

compenl
otor

air
If
excessive
air

leakage
is
found

at

the
valve

replace
idle

compensator
as

an

assembly
Note
that
two
idle
com

pensators
are
mounted
to
air
cleaner

and
that
it
is

necessary
to

plug
the

valve
of
one
of
these
idle

compensa

tors
so
as
to

prevent
air
leak
while

checking
the
other
one

@

CD

I

tl

1
Orifice

2
Rubber
valve

EF225

Fig
EF

16
Checking
idle

compelll
lor

FUEL
FILTER

1

Body

2

Paper
element

3
Cover
1

EFOO5

Fig
EF

18
Sectional
view

of
cartridge

type
fuel
filter

EF

8
Note

When

checking
idle

compensa

tor
on
vehicle
disconnect
hose

leading
to
idle

compensator
and

connect
other
hose
then

carry
out

check
as
descn
bed
above

2

When
bi
metal

temperature
is

above
the

specified
operating

tempera

ture

visually
check
to
see
if
the
valve

is
in

open
position
If

valve
is
not

open
replace
idle

compensator
as
an

assembly

Watcr

temperature
Observe

valve

11t
No

1
Bknctal

60
to
70De

140
to
1580F

NO
2
Bi
metal

70
to

900C

158to
1940F

EF226

Fig
EF
17

Checking
idle

compensator

3
Others

I
Check

hoses
for

correct
installa

tion

distortion
or
cracks

2

Check
rubber
valve
seat
of
idle

compensator
for

sticking
or

any
other

faulty
conditions

REMOVAL

Disconnect
inlet
and
outlet
fuel

lines
from
fuel

fJlter
and
remove
fuel

fJlter

Note

Before

disconnecting
fuel
lines

use
a
container
to

receive
the
fuel

remaining
in
lines

4

Run
the

engine
at

varying
speeds

5

The

pressure
gauge
indicates

static
fuel

pressure
in
the
line

The

gauge
reading
should
be

within
the

following
range

0
21
to
0

27

kg
em2

3
0

to
3

8

psi

Note
If

the
fuel
in
carburetor
float

chamber
has
run
out

and

engine
has

stopped
clip
and

pour
fuel

into

carburetor
Fasten

clip
secure

ly
and

repe
1
static

pressure
test

Pressure
below
the
lower
limit
indi

cates
extreme
wear
on
one

part
or

a

small
amount
of
wear
on
each

working

part
It

also
indicates

ruptured
dia

phragm
worn

warped
dirty
or

gum

ming
valves
and
seats
or
a
weak

diaphragm
return

spring
Pressure

above
the

upper
limit
indicates
an

excessively
strong
tension
of
dia

phragm
return

spring
or
a

diaphragm

that
is
too

tight
Both
of
these
condi

tions

require
the
removal
of

pump

assembly
for

replacement
or

repair

CAPACITY
TEST

The

capacity
test
is

made

only

when
static

pressure
is
within
the

specifications
To

make
this
test

pro

ceed

as
follows

1

Disconnect

pressure
gauge
from

T
connector
and
in
its
vacant

place

install
a

suitable
container

as
a
fuel

sump

2
Run

engine
at
1

000

rpm

3
The

pump
should

deliver
1
000

cc

2
11

US

pt
of
fuel
in

one
minute
or

less

If
little

or
no
fuel
flows
from
the

open
end
of

pipe
it
is
an

indication

that
fuel
line
is

clogged
or

pump
is

malfunctioning

REMOVAL
AND

DISASSEMBLY

Remove
fuel

pump
assembly
by

unscrewing
two

mounting
nuts
and

disassemble
in

the

following
order

1

Separate

upper
body
and
lower

body
by

unscrewing
body
set
screws
Engine
Fuel

2

Take
off

cap
and

cap
gasket
by

removing
cap
screws

3
Unscrew
elbow

and
connector

4
Take
off
valve

retainer

by
un

screwing
two
retainer

screws
and
re

move
two
valves

5
To
remove

diaphragm

press

down
its

center

against
spring
force

With

diaphragm
pressed
down

tilt
it

until
the
end
of

pull
rod
touches
the

inne

wall
of

body
Then
release

diaphragm
to
unhook

push
rod
Be

careful

during
this

operation
not
to

damage
diaphragm
or
oil
se
L

i
J

EFOO7

Fig
EF

20
Remouing
pull
rod

6
Drive
rocker
arm

pin
out
with
a

press
or
hammer

8

o

6

7

8

@

INSPECTION

I

Check

upper
body
and
lower

body
for
cracks

EF
10
I
fuel

pump
cap

2

Cap
gasket

3
Valve

packing

4

fuel

pump
val
e

assembly

S
Valve
retainer

6

Diaphragm
assembly

7

Diaphragm
spring

8
PuRro

9

Lower
body
seal

washer

10
Lower
body
seal

11
Inkl
connector

12
Outlet
connector

13
Rocker
arm

spring

14
Rocker
arm

I
S
Rocker

artyl
side

pin

16
Fuel
pump
packing

17

Spacer
fuel

pump

fo
cylinder
block

EF510

Fig
EF
21
Slruc
ure
of
fuel

pump

2
Check

valve
assembly
for
wear
on

valve
and
valve

spring
Blow
valve

assembly
with
brea
th
to
examine
its

function

3
Check

diaphragm
for

small
holes

carcks
or
wear

4

Check

rocker
arm
for
wear
at
the

mating
portion
with

camshaft

5

Check
rocker
arm

pin
for
wear
A

worn

pin
may
cause
oil

leakage

6
Check
all

other

components
for

any
abnormalities
and

replace
if
neces

sary

DESCRIPTION

INSPECTION

REMOVAL
AND

INSTALLATION

DESCRIPTION

The
electric
fuel

pump
is

adopted

on
air

conditioner

equipped
models
Engine
Fuel

ASSEMBLY

Reverse

the
order
of

disassembly

Closely
observe
the

following
instruc

tions

L

Use
new

gaskets

2

Lubricate
rocker
ann
rocker
arm

link
and

rocker
arm

pin
before
installa

tion
3

To
test
the

function

proceed
as

follows

Position
fuel

pump
assembly
about

I

meter
3
3
ft

above
fuel
level
of

fuel

strainer
and
connect
a

pipe
from

strainer
to
fuel

pump

Operate
rocker

arm
by
hand
If

fuel

is

drawn

up
soon
after
rocker
arm
is

released

fuel

pump
is

functioning

properly

ELECTRIC
FUEL
PUMP

CONTENTS

EF
11

EF
11

EF
12
DISASSEMBL
Y

ASSEMBL
Y

TROUBLE

DIAGNOSES
AND

CORRECTIONS
EF
12

EF
12

The
silicon
transistor

type
fuel

pump

consists
of

a
transistor
diodes
a

sole

I
Tr

lOsistor

6
Ou
tIet
valve

2

Plunger

7
Return

spring

3

Diaphragm

8
Filter

4

Diode

9

Magnet

5

Magnet
coil

10
Inlet
valve

INSPECTION

I
Disconnect
fuel
hose
at

pump

outlet

2

Connect

a
suitable
hose

approxi

mately
6

mm
0

24
in
inner

dia

meter
to

pump
outlet
ev
J

J

Note
If
diameter
is
too
small
the

following

proper
delivery

capacity

cannot
be
obtained
even
if

pump

functions

properly

EF
11
EF
13

noid
a

pump
mechanism
and
filter

parts

I
T
nsistor

2

Re
ist
f
I

3
Dinde

4

Signal
coil

5
Main
coil

6
Resistor
3

7
Zener
dlOdl

8

Resistor
2

EF719

Fig
EF
22
Construction

of
electric

fuel

pump

3

With
hose
outlet
in
a

higher
posi

tion

than

pump

operate
pump
and

check

delivery
capacity
for
more
than

15

seconds

4

The

capacity
should
be
I
400

cc

854
co
in
in
one
minute
or
less

If
no

gasoline
or

only
a

little
flows

from

open
end
of

pipe
with

pump

operated
or
if

pump
does

not
work

perform
the

following
diagnosis

Notes

3
Do
not

connect
battery
in
reverse

polarity
which
if
left
for
a

long

time
would

damage
transitor

circuit
and
disable

pump
Engine
Fuel

b
Do
not
let
fall

pump
as
it

may

damage
electronic

components

c
Do
not

apply
overvoitage
max

l
8Y

Overvoltage
starting

by

quick
charge
or

tage
running

would
deteriorate
or

damage
elec

tronic

components

Fuel

pressure
maximum

0
32

kg
cm
4
6

psi

REMOVAL
AND
INSTALLATION

Flom
fuel
tank

Electric
fuel

pump
is
installed
on

bracket
with
two
bolts
This
bracket
is

located
on
R
H
side
member

adjacent

to
fuel
tank

I
Remove
inlet
hose
from
fuel

pump
Also
remove
outlet
hose
run

ning
to

engine
Receive
fuel

remaining

in
fuel
hose
in
a
suitable
container

2
Disconnect
harness
at

connector

3
Remove
bolts

securing
fuel

pump

to
bracket
and
detach
fuel

pump

4

Installation
is

the
reverse
order
of

removal

9

@

1
Cover

2

Magnet

3
Cover

gasket

4
Filter

5
Gasket

6

Spring
retainer

7
Washer
8
O

ring

9
Inlet
valve

10
Retutn

PIing

11
Plunger

12

Plunger
cylinder

13

Body
To
carburetor

1
Elecuic
fuel

pump

2

Mounting
bracket

3
Fuel
mter

EF72D

Fig
EF
23
Electric
fuel

pump

DISASSEMBLY

Do
not
disassemble
unless

pump
is

faulty

I
Remove

cover
with
wrench
and

take
out
cover
gasket
magnet
and

filter
from

pump
body

2
When

removing
plunger
take
out

spring
retainer
from

plunger
tube

3
Then
take
out
washer
O

ring

inlet
valve
return

spring
and

plunger

from
tube

Note
Do
not
disassemble
electronic

components
If

n

replace

with
new
ones

6

EF721

Fig
EF
24

Exploded
view

of
electric
fuel

pump

EF
12
ASSEMBLY

I

Before

assembly
clean
all

parts

with

gasoline
and

compressed
air

com

pletely

Notes

a
If

gask
t

an
d
fdterare

faulty
r

place

b
Clean

magnet
and
cover
for
fault

c
Take
care
not
to
defonn
thin
tube

d
Assemble

plunger
return

spring

inlet
valve
O

ring
washer
and
set

spring
retainer
in
that
order

e

Assemble
filter

gasket
and
cover

with

f

Tighten
cover
with
wrench
to
the

stopper

If

component
parts
are

dirty
after

disassembly
clean
as
follows

Wash
fIlter
and
strainer
with
clean

gasoline
and
blow
with

compressed

air
When

cleaning
parts
check

fllter
for
fault
If

faulty
replace

Wash

plunger
plunger
cylinder
and

inlet
valve
with
clean

gasoline
and

blow
dust
off

with

compressed
air

2
Check

c
v
m
lI

parts
for
wear

or

damage

If

they
are
found

faulty

replace

them

3

Insert

plunger
assembly
into

plunger
cylinder
of

body
and

apply

electric
current
to
it

Move
the

assembly

up
and
down

If
the

assembly
does
not
move
it

shows

that
the
electric

uuit
is

faulty

and
it
must
be

replaced

Engine
Fuel

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Fuel

pump
fails
to

operate

Fuel

pump
fails
to

discharge
sufficient

flow

Insufficient
fuel

discharge
during

high
speed
travelling

Low
float
level

at

idling

Fuel

pump
is
actuated

more

frequently
than

under
normal
condi

tion

Rattling
noise
Probable
cause

Terminals
or
connections
loose

Rust
on
terminals
or

grounding
metal

Frozen

liquid
in

plunger
or

pump

Clogged
filter

Insufficient
fuel

Air
in

fuel
hose

through
connections

Hose
necked
down
or
bent

Fuel
tank
breather
tube
bent
or
necked

down

Weakened
return

spring

Air
sucked

through
connection
fuel
hose

and
fuel

pump
joint

Fuel
hose
on
suction
side
bent

Clogged
fIlter

Mounting
bolts
loose

EF
13
Corrective
action

Retighten

Clean

Clean

plunger
assembly

Replace
pump
if

plunger
is

stuck
or
seized

Clean

pump
interior
Clean
and

if

necessary

replace
fIlter

Replenish

Apply
a

coating
of
end
sealing

compound
to

connections
and

retighten

Check
and
correct

Check
and
correct

Replace

Apply
a

coating
of
end

sealing
compound
to

connection
and

retighten

Check
and
correct

Clean
or

replace
fIlter

Retighten