1973 DATSUN B110 fuel cap

Air
intake

system
in

trouble

Overheating

Overcooling

Others

NOISY

ENGINE

Car

knocking

Car
knock
when

coasting
ENGINE

Diny
ur

clogged
fuel
strainer

Fuel

pump
will
not
work

properly

Clogged
carburetor

jets

Clogged
air
cleaner

Air

inhaling
from
manifold

gasket
or
carbu

retor

gasket

Insufficient
coolant

Loosened
fan
belt

Worn
or
defective
fan
belt

Defective
thermostat

Defective
water

pump

Clogged
or

leaky
radiator

Defective
radiator
filler

cap

Air

mixing
into

cooling
system

Improper
grade

engine
oil

Incorrect

ignition
timing

Defective
carburetor

lean
mixture

Defective
thermostat

Low

octane
fuel

Improper
tire

pressure

Dragging
brake

Slipping
clutch

Overloading
to

engine

Carbon

knocking

Timing
knocking

Fuel

knocking

Preignition
misusing
of

spark
plug

Incorrect
throttle

opener
adjustment

Trouble
in
PCV
valve

ET
30
Replace

Repair
or

replace

Disassemble
and
clean

Replace
element

Replace
gasket

Replenish

Adjust

Replace

Replace

Replace

Flush

repair
or

replace

Replace

Retighten
each

part
of

cooling
system

Replace
with

proper
grade
oil

Adjust

Overhaul
carburetor

Replace

Replace
with

specified
octane
fuel

Adjust
to

the
specified

pressure

Adjust

Adjust

Use

right

gear
in

driving

Disassemble
cylinder
head
and
remove

carbon

Adjust
ignition
timing

Use

specified
octane
fuel

Use

specified
spark
plug

Adjust
throttle

opener

Replace
PCV
valve

ENGINE

27
Install
the
oil

pump
with
oil
filter

28
Install
the

alternator
fan
and

fan
belt

29
Install
the

fuel

pump

30

Install
the
distributor

assembly

Fig
EM
B7

Timing
maTk

Fig
EM
SS
Distributor
installation

EM
32
Notes
3
Set
the

No
1

piston
to
its

top
dead
center
of

the

compression
stroke

b
Before
installation
return

the
distributor
rotor

approximately
60

degrees
from

its

regular
posi

tion
Insert
the

assembly

meshing
the
distributor

drive

gear
and
driven

gear

After

installation
the
distributor
rotor
should

come

into
contact

with
the
mark
on
the
rotor

cap

fitting
as

shown
in
the

Figure

31

Install
the

spark
plugs
and

connect
the

distributor

to

plug
high
tension

lead
wire

32
Install
the
fuel
hoses

and
tubes

33
Install
the
clutch

cover

assembly

34
Install
the

engine
stingers
and

crankcase
ventilation

hose

35
Dismount

the

engine
from
the

working
stand

Install
the

engine
mountings

FUEl
SYSTEM

FUEL
STRAINER

DESCRIPTION

The

fuel
strainer
is
of
a

cartridge
type
It

uses

paper

element
as
strainer
element
which
can
be

checked
for

condition

from
outside
This
strainer
cannot
be
cleaned

Replace
the
strainer
at
the

specified
service
interval
or
if
it

becomes

clogged
or

restricted
REMOVAL

Disconnect
inlet
and
outlet

fuel
lines
from
fuel

strainer
and

remove
fuel
strainer

Note
Before

disconnecting
fuel
lines
use
a
container
to

receive
the

remaining
fuel
in
lines

r

@
I

I

Il
QY
I

I
I
elementl
3
Cover
@

EF005

Fig
EF
10
Sectional
view

of
caTtridge
type
fuel
stTaineT

FUEL
PUMP

CONTENTS

DESCRIPTION

FUEL
PUMP

TESTING

Static

pressure
test

Capacity
test
EF
5

EF
6

EF
6

EF
6

DESCRIPTION

The
fuel

pump
transfers

gasoline
from
the
tank
to
the

carburetor
in
sufficient

quantity
to
meet

engine
require

ments
at

any

speed
or
load

The
fuel

pump
is
of
the

diaphragm
type
REMOVAL
AND
DISASSEMBLY

INSPECTION

ASSEMBLY
EF
7

EF
B

EF
B

The
fuel

pump
consists
of
a

body
rocker

arm
and
link

assembly
fuel

diaphragm
fuel

diaphragm

spring
seal

inlet
and
outlet
valves

The
fuel

diaphragm
consists
of

specially
treated
rubber

which
is

not
affected

by
gasoline
held

together
with
two

metal
discs

and
a

pull
rod

EF
5

ENGINE

FUEL
PUMP

TESTING

A
fuel

pump
is

operating
properly
when
its

pressure
is

within

specifications
and
its

capacity
is

equal
to
the

engine
5

requirements
at
all

speeds
Pressure
and

cap
lcity
must
be

determined

by
two
tests

with

the

pump
mounted
on
the

engine
Be

sure
that

there

is

gasoline
in
the

tank
when

conducting
these

tests

Fig
EF
11
Schematic
view

of
fuel
pump

Static

pressure
test

The

static

pressure
test
is

conducted
as
follows

Disconnect
the
carburetor
fuel
line
at

the
carburetor

2
Install
the

necessary
adapter
and
tee

fitting
to
the

fuel
line

and
attach
a

suitable

pressure
gauge

Start
and
run

engine
at

varying
speeds

4

The

reading
on
the

gauge
is
the

static
fuel

pressure

and
this
should
remain
within
the

following
limits

0
18

kgJcm2
2

61b

sq
in

Pressure
below
the
lower
limit

indicates
extreme
wear

on
one

part
or
a
small
amount
of
wear

on
each

working

part

They
also
indicate
a

ruptured
diaphragm
worn

warped
dirty
or

gumming
valves

and
seats
or
weak
diaphragm
return

spring
Pressure
above
the

upper
limit

indicates
an

excessively
strong

diaphragm
that
is

too

tight

This
condition

requires
removal

of
the
fuel

pump
as

sembly
for

replacement
or

repair

Capacity
test

The

capacity
test

is
used

only
when
the
static

pressure

is
within

specifications
The

capacity
test
is
conducted
as

follows

1
Disconnect
the

fuel

pipe
at

the
carburetor

2

Place
a
suitable
container
at

the
end

of
the

pipe

3

Start
the

engine
and
run
at
1

000

rpm

4

The

pump
should
deliver
450
cc
I
V
S

p
of
fuel
in

one
minute

or
less

EF
6

FUEL
SYSTEM

If
no

gasoline
or

only
a
little
flows
from

open
end

of

pipe
the
fuel

pipe
is

clogged
or
the

pump
is
malfunction

ing
Before

removing
the

pump
remove
the

gas
tank

cap

disconnect
both
inlet
and
outlet

pipes
and
blow

through

them
with
an
air
hose

to
make
sure
that

they
are
clear

This
will
eliminate

possible
clogged
gas
strainer
in
the

fuel
tank
Reconnect
the

pipes
to
the

pump
and

retest

flow

REMOVAL
AND
DISASSEMBLY

Remove

the
fuel

pump
assembly
by
unscrewing
two

mounting
nuts
and
disassemble
in
the

following
order

1

Separate
the

upper
body
and
the

lower

body
by

unscrewing
the

body
set
screws

2
Take

off
the

cap
and
the

cap
gasket
by
removing
the

cap
screw

3
Unscrew

the
elbow
and
the

connector

4
Take

off
the
valve
retainer

by
unscrewing
two

valve

retainer

screws
Two

valves
are

easily
removed

@

@

GS
5
To
remove
the

diaphragm
diaphragm
spring
lower

body
seal
washer

and
lower

body
seal
from
the

lower

body
press
down

the

diaphragm
counter
to

the
force
of

the

diaphragm

spring
and
while

doing
this
cant
the

diaphragm
so
that
the

rectangular

part
in
the

lower
end
of

the

pull
rod
is

unhooked
from
the
rocker

arm
link

Fig
EF
jJ
StructuTe

of
fuel
pump

EF
7
j

i

I
of

4

Fig
EF
12
Pull
Tad
Temoval

r1
r

f
i

t

1

2

3

4

5

6

7

B

9

10

tt

t2

t3

t4

15

t6

t7

tB

t9

20

2t

22

23

24
Valve
assem

bly

Packing

Retainer

Screw

Cap

Gasket

Screw

Washer

spring

Rocker
arm

Rocker

pin

Rocker
arm

spring

Spacer

Diaphragm
assembly

Retainer

Diaphragm
spring

Washer

spring

Nut

Washer

plain

Gasket

Spacer

Complete
body
lower

Connector
inlet

Connector
outlet

FUEl
SYSTEM

EVAPORATIVE
EMISSION

CONTROL
SYSTEM

CONTENTS

OESCRI
PTION

Flow

guide
valve

MAINTENANCE

AND

TESTING

Checking
fuel
tank

vapor

liquid
separator

and

vapor
vent
I
ins
EF
25

EF

26

EF

26

EF

26

DESCRIPTION

This

system
consists
of

four
basic
elements

indicated

below

I

Fuel
tank

with

positive
sealing
filler

cap
with
relief

valve

2

Vapor

liquid
separator

3

Vapor
vent
line

4
Flow

guide
valve

The
flow

guide
valve

prevents
blow

by

gas
from

flowing
into
the
fuel
tank

and

guides
fresh
air
into
it

preventing
gasoline

vapor
from

escaping
into
the

carbure

tor
air
cleaner

Fl

me
ester

I

f
Flow

Thev
lve

opens
when

thlp
1l

rO

Inch

Hg

O
Positive
unk

venlI1atlon

PCV
hoe
Checking
fuel

tank
vacuum
relief
valve

operation

Checking
flow

guide
valve
EF
27

EF
27

Flow

guide
valve

operates
and
blow

by

gas
and

gasoline

vapor
flow
as
follows

When
the

engine
is
not

running
the

vapor
vent

line

vapor
liquid
separator
and

fuel
tank

are
filled
with

gasoline
vapor
produced
in
the

sealed

type
fuel
tank

A

flow

guide
valve

opens
when
the

gas

pressure
is

above

IOromHg
0
4

in

Hg
The

gas

passed
through
the
flow

guide
valve
2
is

accumulated
in

the
crankcase

Once
the

engine
starts

evaporates
in

the
crankcase

manifold
and

carburetor
air
cleaner

is
sucked
into
the
manifold
for

combustion
When
the

pressure
of
the

sealed

type
fuel

tank

vapor
liquid

separator
and

vapor
vent
line

becomes

negative
by

decreasing
the
fuel
the

flow

guide
valve
I

opens
to
send
fresh
air
from
the
carburetor
air
cleaner

to

the

fuel
tank

lill
K
riquidllepilrflOr

T

VilPOl
vent

line
Positiveteilling

lillercap

Fig
EF
37

Evaporative
emission

control

system

EF
25

ENGINE

ffi68
mmAq
14
5

mAq

3

way
connector

Cock

II
M

nam
e
Flow

guide
valve

This
valve
is
mounted
in

the

engine
compartment

f
tHks
A
F
and
C
are

engraved
in
the

body
of
the

valve
to

indicate
the
connection
of
the

vapor
vent
line

l
l
1

from
Fuel
tank

to
Crankcase

Fig
EF
3B
Flow

guide
valve

MAINTENANCE
AND

TESTING

Checking
of
fuel
tank

vapor
liquid

separator
and

vapor
vent
line

Check
all
hoses
and
fuel
tank
filler

cap

2
Disconnect
the

vapor
vent
line

connecting
flow

guide

valve
to

vapor
liquid
separator

Flow
guide
valve
3
Connect
a
J

way
connector
a
manometer
and
a
l
ul
k

or
an

equivalent
3

wav

change
cock

to
the
end
of
the

vent
line

4

Supply
fresh
air
into
the

vapor
vent
line

through
the

cock
little

by
little

until
the

pressure
becomes
368

romAq

14
5
in

Aq

5

Shut
the
cock

completely
and
leave

it
that

way

6

After
2
5
minutes
measure
the

height
uf
the

liquid
in

the
manometer

7
Variation
of

height
should
remain
within
25

mmAq

1
0
in

Aq

8
When
the

filler

cap
does
not
close

completely
the

height
should

drop
to
zero
in
a
short
time

9
I
f
the

height
docs
not

drop
to
zero

in
a
short
time

when
the
filler

cap
is
removed

it
is
because

of
the

stuffy

hose

Note
In
case
the
vent
line
is

stuffy
the

breathing
in
fuel

tank
is
not
thoroughly
made
thus

causing
insuf

ficient
delivery
of
fuel
to

engine
or

vapor
lock
It

must
therefore
be

repaired
or

replaced

1
m

eparator

1
Fuel
filler
cap

Y

XI

EC029

Fig
EF
39

Checking
evaporative
emission
control

system

EF
26

FUEL
SYSTEM

Checking
fuel
tank
vacuum
relief

valve

operation

Remove
fuel

filler

cap
and
see
if
it
functions

properly

as
follows

Wipe
clean
valve

housing
and
have
it
in

your
mouth

2

Inhale
air
A

slight
resistance

accompanied
by
valve

indicates
that

valve
is
in

good
mechanical
condition

Note

also
that

by
further

inhaling
air

the
resistance
should
be

disappeared
with

valve
clicks

3
If
valve

seems
to
be

clogged
or
if

no
resistance
is

felt

replace

cap
as
an
assembled
unit

1
1

1I

L

CD

hl

cv
CID

t

I
Valve

2
Valve

housing

I
I
Spring

Valve
seat

Fig
EF
40
Fuel

filleT
cap

EF
27
Checking
of
flow

guide
valve

1
Disconnect

all
hoses

connected
to
the

flow

guide

valve

2

While
lower

pressure
air
is

pressed
into

the
flow

guide

valve
from
the
ends

of
vent

line
of

fuel
tank
side

the
air

should

go
through
the
valve
and

flow
to

crankcase
side
If

the

air
does
not

flow
the
valve
should

be

replaced
But

when
the

air
is
blown

from
crankcase
side
it

should
never

flow
to
the

other

two
vent

lines

3
While
the

air
is

pressed
into

the
flow

guide
valve
from

carburetor
air
cleaner

side
it

flows
to
the

fuel
tank
side

and
or

crankcase
side

4
This

valve

opens
when
the

inner

pressure
becomes
10

romHg
0
4
in

Hg
In
case
of

improper
operations
or

breakage
replace
it

iFrom

r
carburetor

air
cleaner

From
fuel
tank

To

r
crankcase

j

iJ
i

ill

1
1

EC030

Fig
EF
4
J

Flow

guide
valve