1973 DATSUN B110 Service Repair Manual

ENGINf

Automatic

temperature
control
air
cleaner

The
automatic

temperature
cuntrol
air
cleaner
is
of
a

special
tvpe
provided
with
a

temperature
sensor
and

vacuum
operated
valve
The
vacuum
acted

upon
the
air

2

I
control
valve
is

controlled
bv
the
sensor
See

Figure

EF

2

J

o

ECQ06

Air
inlet

pipe

2
Vacuum

motor
assembly

3
Temperature
sensor

assem
bly

4
Hot
air

pipe

5
Air
ontrol
valve

Fig
EF
2
Automatic

temperature
control

air
cleaner

If
the

temperature
of
suction
air
is
low

when
the

engine
is

running
the
air
control
valve
closes
the

underhoad
air
inlet

and
introduces
hot
air

through
the

j

I
a

0

Ej
If

f

7
@

t
t
1

Hot
air
I
cover
which
is
installed
on
the
exhaust
manifold
See

Figure
EF
3

I

@
To
manifold

EC007

J
I
Air
inlet

pipe

2
Air
control
valve

3

Diaphragm
spring

4

Diaphragm

5
Vacuum
ho

s

6
Air
bleed
valve
closed

7
Hot
air

pipe

8

Temperature
sensor

as

mbly

Fig
EF
3
Hot
air

delivery
mode

during
cold

engine
operation

EF
2

FUEL

SYSTEM

When
the

temperature
of

suction
air
around
the
sensor

reaches
430C

1l00F
and
above
the
sensor

actuates
to

open
the
air

control
valve

When
the

temperature
of

suction
air
around
the
sensor

further
rises
and

reaches
above
490C

I200F
the
air
control
valve

completely

opens
to

prevent
the

entrance
of
hot

air
and

aHows

underhood
air

alone
to
be
introduced

into
the
carburetor

See

Figure
EF4

u

C
I

1f1

lL
GJ

J
To
manifold

ECOOB

j
1
Air
inlet

pipe

2
Air
control
valve

3

Diaphragm
spring

4

Diaphragm

5
Vacuum
hoses

6
Air
bleed
valve

fully

open

7
H
t
air

pipe

8

Temperature
sensor

a5

mbly
Under
hood
air

I
I

Fig
EF
4

Underhood
air

delivery
mode

during
hot

engine
operation

The
air
control

valve
acts
in

the
manner
described

above
the

temperature
of
suction
air

around
the
sensor
is
always
kept
about
460C

I150F
See

Figure
EF
5

r
9

t
t
T
I

I

I

fY
ID

I

J
To
manifold

E
C009

I
Air
inlet

pipe

2
Air
control
valve

3

Diaphragm
spring

4

Diaphragm

5

Vacuum
hoses

6
Air

bleed
valve

partially

open

7
Hot
air

pipe

8

Temperature
sensor

assembly
Under
hood
air

J

Hot
air

Fig
EF
5

Regulating
air

delivery
mode

EF
3

ENGINE

When
the

engine
is

operating
under

heavy
load
the

air
control
valve

fully
opens
the
underhood
air

inlet
to

obtain
full

power
regardless
of
the

temperature
around

sensor

TEMPERATURE
SENSOR

Removal
and

installation

Removal

Hatten
the

tabs
of

clip
with

pliers

2
Pull
out
hoses

Note
Note
the

respective
positions
of
the
hoses
from

which

they
were
removed

3

Pry
the

tab
of

clip
with
a
screwdriver

4
Take

off
the
sensor
and

clip

I

@

f
6

7

CID

f

j
EC019

1

Pipe

2
Catch

3
Fixed
with
adhesive

4
Hose

5
Tab

6

Clip

7

Gasket
rubber

Fig
EF
6

Removing
sensor

Installation

I
Install
the

sensor
and

gasket
assembly
in
the

proper

positions

EC020

Fig
EF
7

Installing
sensor
This
control

of
carburetor
air

temperatures
allows

leaner
carburetor

calibration
with

accompanying
reduced

emissions
than

conventional
controls
and

also
eliminates

carburetor

icing

2
Insert

clip
Be

sure
to
hold
the

sensor
at
the

portion

A
in

Figure
EF
7
to
avoid

damage

Press
fit
the

clips
into
the

pipe
while

straightening
the

tabs

Note
Use

care
not
to

damage
the
sensor

EC021

Fig
EF
B

InseTting
clip

3
COIUlect
the
hoses
to
their

proper
positions

EC022

Fig
EF
9

Connecting
hoses

EF
4

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

ENGINE

INSPECTION

Check

the

upper
and
lower
bodies
for
cracks

2

Check
the
valve

assembly
for

wear
of
the
valve
and

valve

spring
Blow
the
valve

assembly
by
breath
to

examine
its

function

3

Check
the

diaphragm
for
small
holes
cracks

and

wear

4

Check
the
rocker

arm
for
wear
at
the

portion
in

contact
with

the
camshaft

5

Check
the
rocker
arm

pin
for
wear
since
a
worn

pin

may
cause
oil

leakage

6

Check
all
other

components
for

any
abnormalities

and

replace
with
new

parts
as

required
ASSEMBLY

Assembly
is
done
in
reverse
order
of

disassembly
For

reassembly
and

reinstallation
the

following
matters

should
be
noted

Use
new

gasket

2
Lubricate
the
rocker
arm

link
rocker
arm

pin
and

lever

pin
before
installation

3
To

test
the
function

position
the

fuel

pump
assem

bly
about
I

meter
3
3
ft
above
fuel
level
with
a

pipe

connecting
the
fuel

pump
and
the
fuel

strainer
and

operate
the
rocker

afm

by
hand
If
fuel
is
drawn

up
soon

after
the
rocker
arm
is
released

the
function
of
the

pump

is

satisfactory

CARBURETOR

CONTENTS

DESCRIPTION

STRUCTURE
AND
OPERATION
EF

8

EF

9

EF
10

EF
11

EF
12

EF
12

EF
12

EF
14

EF
14

EF
15

EF
15

EF
16

EF

16
Primary
system

Secondary
system

Anti

dieseling
solenoid
valve

Float

system

Electric
automatic
choke

ADJUSTMENT

Idling
adjustment

Fuel
level

adjustment

Fast
idle

adjustment

Vacuum
break

adjustment

Choke
un
loader

adjustment

DESCRIPTION

The
carburetors
are

of
a

downdraft

type
which
is

designed
and
built

to
increase

power
and

fuel

economy
as
Bi
metal

setting

Adjustment
of

interlock

opening
of

primary
and

secondary
throttle
valves

Dash

pot
adjustment

MAJOR
SERVICE
OPERATIONS

Removal

Disassembly

Cleaning
and

inspection

Assembly
and
installation

JETS

SERVICE
DATA
AND
SPECIFICATIONS

TROUBLE
DIAGNOSES
AND

CORRECTIONS
EF
17

EF
18

EF
18

EF
19

EF
19

EF
19

EF
21

EF
22

EF
22

EF
22

EF
22

well
as
to
reduce
the

emission
of
exhaust

gases

These
carburetors

present
several
distinct
features
of

importance
to
the

car
owners

A

summary
of
features
is
as
follows

EF
8

FUEl
SYSTEM

Secondary
throttle
valve

is

operated
by
throttle
lever

The

high

power
and

good
acceleration
are

gained
with

combination
of

the

auxiliary
valve

2

Accelerating
pump
gives
excellent

acceleration

3

The

power
valve
mechanism
is
of
a

vacuum
actuated

boost

type
and

improves

high
speed
driving

4
The

throttle

opener
control

system
Refer
to
Section

ET

incorporates
a

servo

diaphragm
The
servo
dia

phragm
helps
open
the
throttle

valve
at
a

decreasing
speed

so
as

to
reduce

the
emission
of

hydrocarbons
to
a

minimum

5
An

anti
dieseling
solenoid

is
used
as
a

means
of

preventing
dieseling
When
the

ignition
key
is
turned
off
the
fuel

passage
involved
in
the
slow

system
is

closed

and
the
fuel

supply
is
shut

down

completely

6
In

the
choke

mechanism
an

electric
automatic

choke

is
used
to

automatically
control
the
choke
valve

operation

during
the
warm

up
of
the

engine

7
The
carburetor

for
automatic
transmission
is

equipped
with
so
called

dash

pot
that

is
it
makes
smooth

decelerating
without

engine
stall
at

any

operating
condi

tion

These

carburetors
are

quite
similar
in

appearance
as

explained
above

except
the

dash

pot
for
the
au
tomatic

transmission
model
The

differences
in

performance
are

explained
in
the

following
as

necessary

for
Manual
transmission

for
4utomatic
transmission

Fig
EF
14
External
view

of
carburetor

STRUCTURE
AND
OPERATION

These

carburetors
consist
of

the

primary
system
for

normal

running
and

secondary
system
for
full

load

running
The

float

system
which
is

commonly
used

by
the
primary
and

secondary
systems
the

secondary
switch
over

mechanism

accelerating
mechanism
etc
are

also
at

tached

The
anti

dieseling
solenoid
valve
and
the

power
valve

mechanism

are
used

The

carburetor
is
of
down
draft
two
barrel

type

EF
9