1977 DATSUN PICK-UP fuel pump

DATSUN
PICK
UP

MODEL
620
SERIES

l
NISSAN

I

NISSAN
MOTOR
CO
LTD

TOKYO
JAPAN
SECTION
EF

ENGINE

FUEL

AUTOMATIC
TEMPERATURE

CONTROL
A
T
C
l

AIR
CLEANER

IDLE
COMPENSATOR

FUEL
FILTER

MECHANICAL
FUEL
PUMP

ELECTRIC
FUEL
PUMP

CARBURETOR
H
2

H
7

H

8

H

9

H

ll

H
14

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

DESCRIPTION

FUEL

PUMP
TESTING

STATIC
PRESSURE
TEST

CAPACITY
TEST

DESCRIPTION

The
fuel

pump
transfers
fuel
from

the
tank
to
the
carburetor
in
sufficient

quantity
to
meet
the

engine
require

ments
at

any
speed
or

load

The
fuel

pump
is
a

pulsating
type

designed
for

easy
maintenance
It

con

sists
of
a

body
a

rocker
arm

assembly

a

fuel

diaphragm
a
fuel

diaphragm

spring
seal
inlet
and
outlet

valves

Figure
EF
19

shows
a
cross
sectional

view
of
the

pump

The
fuel

diaphragm
consists

of

specially
treated
rubber
which
is

not

affected

by

gasoline
and
held
in

place

by
two

metal
discs
and

a

pull
rod

FUEL

PUMP

TESTING

A
fuel

pump
is

operating

properly

when
its

pressure
is

within

specifica

tions

and
its

capacity
is

equal
to
the

engine
s

requirements
at
all

speeds

Pressure
and

capacity
must
be
deter

mined

by
two
tests
while
the

pump
is

still

mounted
on
the

engine
Be
sure

there
is
fuel
in

the
tank
when

carrying

out
the
tests
Engine
Fuel

MECHANICAL
FUEL
PUMP

CONTENTS

EF
9

EF
9

EF
9

EF
10
REMOVAL
AND
DISASSEMBLY

INSPECTION

ASSEMBL
Y
EF

10

EF
10

EF

11

1

1

Outlet
valve

2

Diaphragm

3

Diaphragm
spring

4
Inlet
valve

S
Rocker
ann
EF006

Fig
EF
19
Schematic
view

of
fuel
pump

STATIC
PRESSURE
TEST

The
static

pressure
test
should
be

made
as
follows

I
Disconnect
fuel
line
between
car

buretor
and
fuel

pump

2
Connect
a
rubber
hose
to
each

open
end
of
a
T
connector
and
con

nect
this
connector
hose

assembly
be

tween
carburetor
and
fuel

pump
Note
Locate
this
T
connector
as

close
to

carburetor
as

possible

3
Connect
a

suitable

pressure
gauge

to

the

opening
of
T
connector
and

fasten
hose
between
carburetor
and

T
connector
with

a

clip
securely

EF
9

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

Engine
Fuel

CARBURETOR

CONTENTS

DESCRIPTION

EF
14
CHOKE
UNLOADER

EF
23

STRUCTURE
AND

OPERATION
EF
14

ELECTRIC
AUTOMATIC
CHOKE
EF

24

PRIMARY
SYSTEM

EF
15
INTERLOCK
OPENING
OF
PRIMARY
AND

SECONDARY

SYSTEM
EF
16
SECONDARY
THROTTLE
VALVE

EF
24

ANTI
DIESELING

SYSTEM
EF
17
DASH
POT

EF
25

FLOAT

SYSTEM
EF
18
ACCELERATING
PUMP

EF

25

BOOST
CONTROLLED

DECELERATION
ANTI
DIESELING
SOLENOID
VALVE

EF

25

DEVICE

B
C
D
D
EF
1B

B
C

D
D
CIRCUIT
WITH

FUNCTION

ELECTRIC

AUTOMATIC

CHOKE
EF
20
TEST

CONNECTOR

EF
25

DASH
POT
SYSTEM
EF
20

ALTITUDE
COMPENSATOR

ALTITUDE

COMPENSATOR

California
modelsl
EF

29

California

models

EF
20
MAJOR
SERVICE

OPERATION
EF

29

ADJUSTMENT
AND

INSPECTION
EF
21
REMOVAL
EF
29

CARBURETOR
IDLE
RPM
AND
DISASSEMBLY
AND
ASSEMBLY
EF

30

MIXTURE

RATIO

EF
21
CLEANING
AND

INSPECTION
EF
34

FUEL
LEVEL

EF
22
SERVICE
DATA
AND

SPECIFICATIONS
EF

35

FAST

IDLE

EF
22
TROU8LE

DIAGNOSES
AND

VACUUM
BREAK

EF
23
CORRECTIONS
EF

36

DESCRIPTION

The

carburetors
are
of

down
draft

two

barrel

types
which

produce
the

optimum
air
fuel
mixture
under

all

operating
conditions

They
present
several

distinct

features
of

importance
to
the

vehicle

owners

A

summary
of
the

features
is

as

follows

1
A

slow
economizer
to

make
a

smooth

connection
with

acceleration

or
deceleration

during
light
load

run

ning

It

also

assures
stable
low

speed

performance

2

An
idle

limiter
to

reduce
harmful

exhaust
emissions
to

a
minimum
3
A

B
C
D

D

device
for

reducing

hydrocarbon
H
C
emissions

4

An

electric
automatic

choke
to

facilitate
cold

starting
and
to
reduce

exhaust
emissions

5

An
anti

dieseling
solenoid
to

eliminate

dieseling
run

on

6
A

power
valve

or
vacuum
actu

ated
booster
to

ensure

smooth

high

speed
operation

7

The

carburetor

comes

equipped

with
dash

pot
which
ensures

smooth

deceleration

without

engine
stall

under

all

operating
conditions

8

The
hand

operated
altitude

com

pensator
is

installed
in
the
California

models

EF
14
STRUCTURE
AND

OPERATION

These

carburetors
consist
of

a

primary
system
for

normal

running

and
a

secondary

system
for
full
load

running

A

float

system
common
to
both

primary
and

secondary
systems
a
se

condary
switch

over
mechanism

an

accelerating
mechanism
etc
are

also

attached

An

anti

dieseling
solenoid
valve

and

a

power
valve
mechanism
are
also

installed

The
hand

operated
altitude

com

pensator
corrects
air

fuel
mixture

to

an

optimum
ratio