1973 DATSUN B110 fuel cap

ENGINE
CONTROL
FUEL
EXHAUST
SYSTEM

For
all
models
fuel
tank

capacity
has
been
increased
in

response
to
the
increased

engine
output
Location
and

mounting
strength
are

improved
for

improvement
of

safety

Sedan
40

l
101
2
US

gal

8

3
4

Imp
gal

Van
38
l
10
US

gal

8

3
8

Imp

gal

Coupe
38
l
10

US

gal

8
3
8

Imp
gal
and

completely
drain
fuel

2
Remove
the
fuel
line
connector

3
Remove
the

luggage

compartment
finishing

4
Remove
four
bolts
used
to

secure
the
fuel
tank

5
Loosen
the
hose

clamp

f

r

II

J

y
I

0

I

V

Ii

i
iJb
Also
for

piping
consideration
has
been

given
on
the

safety
To
be
more

specifically
the
fuel
line

coming
out

from
the
fuel
tank
is
laid
inside
the
rear
side
member
so

that
the

fuel
line
is

protected
from

gravel
and

other

interferences
from
road
In
the
front
floor
section
the

fuel
line
is
laid
inside
a
tunnel
and
thus
fuel
line

reaches

the

engine
compartment

In
addition
the
fuel
strainer
and
fuel
tank
outlet
units

connect
the
fuel
line
with
rubber
hoses
and
for
aU
other

sections

bandy
tube
is

used
Fig
FE
9
Drain

plug
position

Replacement

Remove
the
drain

plug
from
the

fuel
tank
bottom
6
Disconnect
cable
to
the
unit

gauge

7
Dismount
the
fuel
tank

f

I

Y

L
ll

C

jjhrr
@

Fig
FE
10
Fuel
tank
14nit
installation

FE
5

BODY

ELECTRICAL

Distributor
Secure

ground
of

ignition
coil

Secure
contact
of

carbon
electric

pole
and

rotor

Eliminate
excessive

tip
on
the

rotor

pole
or

cap
pole
by
scrubbing
with

a
screwdriver

Check

stagger
between

rotor
and

stator

Charging

system

Sound
of

alternating
current

pre

sents
Alternator
Install
a
0
5

l
F

capacitor

on

charging
terminal
A

Note
Do
not
use

capacitor
ex

cessively

If

capacity
is
used
ex

cessively
the
alternator
coil

will
be
broken

When

the
accelerator

pedal
is
de

pressed
or
released
noise

presents
Regulator
Install
a
0
5
l
F

capacitor
on
A

terrninal
of
the

voltage
regulator

Supplement
equipment

When

engine
starts
noise

presents

Noise

still

presents
even
after

stopping
the

engine
Operative
noise

of
ther

rnometer
and
fuel

gauge
Install
0
1
l

F

capacitor
between

terminal
and

ground
wire

Note
If

a

capacitor
having
ex

cessive

capacity
is
used
indi

cation
of
meter
will
be
devi

ated

Noise

presents
when
horn
is
blown

Horn
Install
a
0
5

IF

capacitor
on
the

horn

relay
terminal
or
horn

switch

Noise

presents
when
turn

signal

lamps
are

operated
Flasher
unit
Install
a
0

5
l
F

capacitor

Note
a
Be

sure
to
locate

capacitor
most
near

position

of
noise

source
and

connect
in

parallel
completely

d
Make

installation
and

conneCtion

securely

b

Cut
lead

wire
as
short
as

possible

c
Ground
wire
should
be

placed
on
the

body
e

Carefully
identify

marks
IN
or
OUT

BE
33

GENERAL
INFORMATION

steering
wheel

should
be
secured
to
maintain
a

straight

ahead

position

TIE
DOWN

The

front
tie
down
hook
is

used
the

both
front
end
of
tension
rod
Do
not

apply
the
hook
at
the
center
of

tension
rod
or

suspension
member

The
rear
tie
down
hook
is
used
the

both
front
shackle

of

rear

spring

APPROXIMATE
REFILL
CAPACITY

Liter
U
S
A

measure

I
Imp
measure

Sedan

Fuel
tank

Coupe

with
heater

Cooling
system

without
heater
40
L

38

L

4
9

L

4
2
L

2
7
L

0
54

L

1
2
L

5
5
L

0
75
L

0
24

L
Oil

pan

Oilf1lter

Transmission

case
Manual

Automatic

Differential

case

Steering
gear
box

RECOMMENDED

GASOLINE
FUEL

Use
a
no
lead

or
low
lead

gasoline
with
a
minimum

octane

rating
of
87
the

average
of
the
Research
and
1O

gal
8Y

gal

10

gal
8

gal

5

v

qt
4

M
qt

4
Y
6

qt
3

Y

qt

2Ji

qt
2

qt

1

pt
I

pt

2

pt
2

pt

5Ji

qt
4

qt

1

pt
1

pt

pt
pi

Motor
Octane
Numbers
in
the
U
S

When
the

figure
is

based
on
the
Research

Octane
Number
use
a

gasoline

with

a
minimum
octane

rating
of

91
RON
in

Canada

RECOMMENDED
LUBRICANTS

GI
5
r

EMISSION
CONTROL
AND
TUNE
UP

EMISSION
CONTROL
SYSTEM

AN
D

ENGINE
TUNE
UP

CONTENTS

BASIC
MECHANICAL
SYSTEM
ET

Checking
and

adjusting
dash

pot

Adjusting
intake
and
exhaust
valve
automatic
transmission
model

only
ET
9

clearances
ET
1

Checking
carburetor
return

spring
ET
9

Checking
and

adjustin9
drive
belt
ET
2

Checking
choke
mechanism
choke
valve

Retightening
cylinder
head
bolts
manifold
and

linkagel
ET
9

nuts
and
carburetor

securing
nuts
ET
2

Checking
anti

dieseling
solenoid
ET
9

Checking
engine
oil
ET
2

Replacing
fuel
filter
ET
10

Replacing
oil
filter
ET
3

Checking
fuel
lines
hoses

pipings

Changing
engine
coolant
L
L
C
ET
3
connections
etc
ET10

Checking
cooling
system
hoses
and
THROTTLE
OPENER

CONTROL
SYSTEM

ET
10

connections

ET
4
Checking
and

adjusting
throttle

opener
ET
13

Checking
vacuum

fittings
hoses
and
TRANSMISSION
CONTROLLED
VACUUM

connections

ET
4
ADVANCE
SYSTEM

ET
17

Checking
engine
compression
ET
4
Checking
electrical
advance
control

system
ET
19

Checking
exhaust
manifold
heat
control
AUTOMATIC
TEMPERATURE
CONTROL
AIR

valve

ET
5
CLEANER
A
T
C
AIR
CLEANER

ET
20

IGNITION
AND
FUEL
SYSTEM

ET
5
Replacing
carburetor
air
cleaner
filter

ET
20

Checking
battery
ET
5
Checking
hot
air
control
valve

ET
20

Checking
and

adjusting
ignition
timing

ET
5
CRANKCASE
EMISSION
CONTROL

Checking
or

replacing
distributor
breaker
SYSTEM

ET
22

point
condenser
and

spark
plugs
ET
6
Checking
or

replacing
PCV
valve

ET
23

Checking
distributor

ignition
wiring
and

Checking
ventilation
hoses

ET
23

ignition
coil

ET
7
EVAPORATIVE
EMISSION
CONTROL

Checking
distributor

cap
and
rotor

ET
7
SYSTEM
ET
23

Adjusting
carburetor
id
Ie

rpm
and

Checking
engine
compartment
hose

mixture
ratio

ET

8
connections
and
fuel

vapor
control
valves
ET
23

Checking
fuel
tank

vacuum
relief
valve

operation
ET
24

BASIC
MECHANICAL
SYSTEM
1
Start

engine
and
run
it

until
it
is
heated
to

operating

temperature
or
at
least
more
than
800C

I760F
of

engine
oil

temperature
then

stop
engine
Adjusting
intake
and
exhaust

valve
clearances

Valve
clearance

adjustment
should
be
made
while

engine
is

stationary

To

adjust
proceed
as
follows
2
Rotate
crankshaft
to

bring
No
1

cylinder
in

top
dead

center
on
its

compression
stroke

3

Remove
valve
rocker
cover

to

gain
access
to
valve

ET
1

EMISSION
CONTROL
AND

TUNE
UP

reading
cylinders
through
spark
plug
hole

Repeat

compression
check
on
these

cylinders

1

If

compression
improves
considerably

piston
rings

are
defective

2
If

compression
does
not

improve
valves
are

sticking

or

seating
improperly

3
If
two

adjacent
cylinders
indicate
low

compression

and

injecting
oil
on

pistons
does
not
increase

compres

sion
the

cause

may
be
a

cylinder
head

gasket
leak

between
the

cylinders
Engine
oil
and
coolant

in

cylinder
could
result
from
this

problem

Compression
pressure

12
S
to
14
S

kg
cm2

178
to

206

psi
at
3S0

rpm

Checking
exhaust
manifold
heat

control

valve

Check
heat

control
valve
for

proper
operation
If
it

does
not

operate
properly
trouble
is
due
to

excess
carbon

on
shaft
or

damaged
shaft
Clean
if

necessary
The
bimetal

should
be
also
checked
for

proper
function

IGNITION

AND

FUEL
SYSTEM

Checking

battery

Check

electrolyte
level
in
each

battery
celL

L

Unscrew
each

filler

cap
and

inspect
fluid
leveL
If

fluid

level
is

low
add

distilled
water
to

bring
level

up
to

app
roximately
10
to
20

mm
0

3937
to
0
7874
in
above

plates
Do
not
overfilL

2
Measure

specific
gravity
of

battery
electrolyte
ET002

Fig
ET
B

Checking
the

specific
gravity
of

battery
electrolyte

Permissible
Full

charge
value

value

at
200C
68OF

Frigid
climates
Over
1
22
1
28

Tropical
climates
Over
1
18
1
23

Other
climates
Over
L
20
1
26

Clean
the

top
of

battery
and
terminals
with
a
solu
lion

of

baking
soda

and
water
Rinse
off
and

dry
with

compressed
air

The

top
of

battery
must
be
clean
to

prevent
current

leakage
between
terminals
and
from

positive
terminal
to

hold
down

clamp

In
addition
to
current

leakage
prolonged
accumulation

of

acid
and
dirt
on
the

top
of

battery
may
cause

blistering

of

the
material

covering
connector

straps
and
corrosion

of

straps
After

tightening
terminals
coat
them
with

petro

laturn

vaseline
to

protect
them
from
corrosion

Checking
and

adjusting
ignition

timing

I

Check

spark

plugs
and
distributor
breaker

points
for

condition

2

Thoroughly
wipe
off
dirt

and
dust
from

timing
marks

on
crank

pulley
and
front

cover

3
Warm

up
engine
sufficiently

ET
5

EMISSION
CONTROL
AND

TUNE
UP

CD

@

Fresh
air

Blow

by

gas

Air
used
in

filtering
oil
1
PCV
valve

2
Flame
arrester

3
Oil
filler

cap

4

Baffle

plate
and

steel
net

E
C002

Fig
ET
J8
Crankcase
emission
control

system
at

full
throttle

open

Checking
and

replacing
PCV
valve

Test
PCV

valve
in
accordance
with
the

following

me
thod

With

engine
running
at
idle
remove
the
ventilator
hose

from
PCV

valve
If
the
valve
is

working
a

hissing
noise

will
be

heard
as
air

passes
through
the
valve
and

a

strong

vacuum
should
be
felt

immediately
when

a

finger
is

placed

over
the
valve
inlet
If
the
valve
is

plugged
replace
with

a

new
one
Check
for

deposit
plugging
in
the
hose
Clean
if

necessary

Intake
manifold

l

illlr
nnnl

UUUU
l
I

G

EC014

FigET
39
Cross
sectional
view

of
PCV
valve
Checking
ventilation
hoses

I
Check
hoses

and
hose
connections
for
leaks

2
Disconnect

all
hoses
and
blow
them

out
with

compressed
air

If

any
hose
can
not
be
free
of

obstructions

replace

with
a

new
one

Insure

that
the
flame
arrester
is

surely
inserted
in

the

hose

between
the
air
cleaner
and
rocker

cover

EVAPORATIVE
EMISSION

CONTROL
SYSTEM

Checking
engine
compartment
hose

connections
and
fuel

vapor
control

valves

Checking
fuel
tank

vapor
liquid
separator
and

vapor

vent
line

I

Check
all
hoses
and
fuel
tank

ftIler

cap

2

Disconnect
the

vapor
vent
line

connecting
flow

guide
valve
to

vapor
liquid

separator

ET
23

ENGINE

3
Connect
a
3

way
connector
a

manometer
and
a

cock
or
an

equivalent
3

way
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

mm

Aq
14
5
in

Aq

5
Shut
the
cock

completely
and

leave
it
that

way

6
After
2
5
minutes
measure
the

height
of
the

liquid

in
the
manometer

7
Variation
of

height
should
remain
within
254

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

If
the

height
does
not

drop
to
zero
in
a

short
time

when
the

filler

cap
is
removed
it
is
the
cause
of
the

stuffy
hose

Note
In

case
the
vent
line
is

stuffy
the

breathing
in

fuel

tank
is
not

thoroughly
made
thus

causing

insufficient

delivery
of
fuel
to

engine
or

vapor

lock

It
must
therefore
be

repaired
or

replaced

3

way

connector

Cock

Air

Manometer
Vapor
liquid

seearator

Flow

guide
valve

E

CQ29

Fig
ET
40

Checking
evaporative
emission
control

system

Checking
flow

guide
valve

I
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
the
carburetor
air

cleaner
side

it
flows
to
the

fuel

tank
side
and
or

crankcase
side

4

This
valve

opens
when
the

inner

pressure
is
10

mmHg
0
4
in

Hg
In

case
of

improper

operations
or

breakage
replace
it

From

carburetor

air
cleaner

From
fuel
tank

i

I
I

ti

i

i

1
1

i
To
ran
kcase

E
C030

Fig
ET
41
Flow

guide
valve

Checking
fuel
tank

vaCCUID
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

T

1i
v

rUr1f
AlI
j

r
I
r
tLMJJl

rr
L

cc

11

J
v

II

4J
L

Valve
I

valve
seat

Spring
Valve

housing

Fig
ET

42
Fuel

filler
cap

ET
24

EMISSION
CONTROL
AND

TUNE
UP

Trouble

shooting
procedure
on

starting
circuit

Switch

on
the

starting
motor

with

light
put
on

When

light
goes
off
or
dims

considerably

a
Check

battery

b
Check
cable
for
connection

c

Check
starter
motor

When

light
stays
bright

a
Check

wiring
connection
between

battery

and
starter
motor

b

Check
starter
switch

c
Check
starter
motor

ENGINE
WILL
CRANK
NORMALLY
BUT
WILL
NOT
START

In

this
case

following
trouble
causes

may
exist
In

the
most
causes

ignition
system
or

fuel

system
is
in
trouble

Ignition
system
in

trouble

Fuel

system
in
trouble

Valve
mechanism
does
not

work

properly

Low

compression

Check

spark
plug
first
in
accordance

with
the

following

procedure

Disconnect

high
tension

cable
from
one

spark
plug
and
hold

it

about
10
rom

0
4
in

away
from
the

engine
metal

part
and

crank
the

engine

Good

spark
occurs
a
Check

spark
plug

b
Check

ignition
timing

Check
fuel

system

d
Check

cylinder
compression

No

spark
occurs
Check

the
current
flow

in

primary
circuit

Very
high
current

Inspect
primary
circuit
for
short

Check
breaker

point
for

operation

Low

or
no
current
Check
for
loose
terminal
or
disconnection

in

primary
circuit

Check
for

burned

points

Ignition
system
in
trouble

Burned
distributor

point
Repair
or

replace

Improper
point
gap
Adjust

Defective

capacitor
Replace

Rotor

cap
and
rotor
leak

Replace

ET
27

ti