fuel consumption DATSUN 210 1979 Service Manual

Page 34 of 548


Condition

Othen

NOISY
ENGINE

Cor

knockillll

M8chanicol

knocking

Crankshaft

bearing

knocking

Connecting
rod

bearing
knocking

Piston
and

cylinder

noise

Piston

pin
noise

Water

pump
noise

Air

pump
noise

Others
Engine
Tune

up

Probable
cause

Improper
octane
fuel

Improper
tire

pressure

Dragging
brake

Dutch

slipping

Overloaded

engine

Carbon

knocking

Timing
knocking

Fuel

knocking

Preignition
miswing
of

spark
plug

This

strong
dull
noise
increases
when

engine

is
occelerated
To
locate
the

place
cause
a

misfire
on
each

cylinder
If
the
noise

stops

by
the
misfire
this

cylinder

generates
the

noise

This

is
a
little

higher
pitched
noise
than
the

crankshaft

knocking
and
also
increases

when

engine
is
accelerated
Cause
a
misfire

on
each

cylinder
and
if
the
noise
diminishes

almost

completely
this
crankshaft

bearing

generates
the
noise

When

you
hear
an

overlapping
metalic
noise

which
increases
its

magnitude
with
the

revolution
of

engine
and
which
decreases
as

engil
e
is
warmed

up
this
noise
is
caused

by

piston
and

cylinder
To
locate
the

place

cause
a
misfire
on
each

cylinder

This

noise
is
heared
at
each

highest
and

lowest
dead
end
of

piston
To
locate
the

place
cause
a
misfire

on
each

cylinder

This
noise

may
be
caused

by
worn
or

damaged
b

arings
or

by
the
uneven
surface

of

sliding
parts

Damaged
air

pump
Except
Canada
and
FU

models

An

improper
adjustment
of
valve
clearance

Noise
of

timing
chain

An
excessive
end

play
on
crankshaft

Noisy
E
F
E

valve
shaft

H20
Corrective
action

Replace
with

specified
octane
fuel

Inflate
to

sptcifled
pressure

Adjust

Adjwt

Use

right
gear
in

driving

Disassemble

cylinder
head

and
remove

carbon

Adjust
ignition
timing

Use

specified
octane
fuel

Use

specified

spark
plug

This
is
caused

by
worn
or

damaged
bearings

or

unevenly
worn
crankshaft
Renew

bearings
and

adjust
or

change
crankshaft

Check
lubrication

system

Same
as
the
case
of
crankshaft

bearings

This

may
cause
an
abnormal

wearing
of

cylinder
and
lower

compression
which
in

turn
will
cause
a
lower
out

put
power
and

excess
ive
consumption
of
oil

Overhaul

engine

This

may
cause
a
wear
on

piston
pin
or

piston
pin
hole

Renew

piston
and

piston
pin
assembly

Replace
water

pump
with
a
new
one

Repair
or

replace

Adjust

Adjust
the
tension
of
chain

Disassemble

engine
and
new
main

beaung

Repair

Page 35 of 548


Condition

ABNORMAL

COMBUSTION

backfire
afterfire

run
on
etc

Improper
ignition
timing

Fuel

system
out
of

order

Feulty
cylinder
heed

etc

Others

EXCESSIVE
OIL

CONSUMPTION

Oilleek8111
Engine
Tune

up

Probable
cause

Surging
A
T
C
air

cleaner
vacuum
motor

Note
This
noise
will
be
hmnl
when
clutch

iI

disengaged

We
r
on
clutch

pilot

bushing

Not
e
This
noise
will
be
heared
when

utch
iI

disengaged

Improper
ignition
timing

Improper
heal

range
of

spark
plugs

Damaged
carburetor
or
manifold

gasket

backfire
aftedire

Clogged
carburetor

jet

Improper
function
of
the
float

Uneven

idling
Run
on

Improperly
adjusted
T
O
C
S
set

pressure

Except
FU

models

Malfunction
of
anti

dieseling
solenoid
valve

Malfunction
of
fuel
shut
off

system
FU

models

Malfunction

or
auto
hoke

Improper
y

adjusted
valve
clearance

Excess
carbon

in
combustion
chamber

Da
laged
alve

spring

backfire
after
he

Malfunction
of
A
T
C
air
cleaner

Inoperative
anti4lackfire
valve

Loose
oil

tain
plUI

ose
or

damaged
oil

pan
gasket

Loose
or

damaled
chain
cover

gasket

Wom
oil
seal
in
front

and
rear
of
crankshaft

Loo
or

damaged
locker

cover

gasket

Improper
lilhtening
of

oU
filter

Loose
or

damaled
oil

pressure
switch

ET
21
Corrective
action

Repair
or

replace

Renew
bush

and

adjust
drive
shaft

Adjust
ignition
liming

Use

specified
spark
plugs

Replace
them

with
new

parts

Disassemble
carburetor
and
check
it

Adjust
the
level
and
check
needle
valve

Adjust

Adjust

Check

or

replace

Check
fuel
shut
off

system

Adjust
or
re

place
necessary

Adjust

Adjust

Remove
head
and

get
rid
of
carbon

Replace
it
wit
a

new
one

Check
for
loose
vacuum
hoses

Replace
if

necessary

Replace

Tighten
it

Renew

lasket
or

tighten
iI

Renew

gasket
or

lighten
it

Renew
oil
seal

Renew

gasket
r

lighten
it
but

not
too

much

Renew

gasket
and

tighten
it
with
the

proper

torque

Renew
oil

pressure
switch
or

tighten
it

Page 36 of 548


Condition

Ex
iv
oil

consumption

Odlen

POOR
FUEL

ECONOMY

See
the
explanation

oI
thtI

power
cIec

01hen

PROBLEM
IN

OTHER

FUNCTIONS

t
1

oil

pre

E
eronthe

lIiding
par1J

Scuffing
oIlliding

par1J
Engine
Tune

up

Probable
cause

Cylinder
and

piston
wear

Improper
lOcation
of

pi5ton
ring

gap
or

reversely
assembled

piston
ring

Damage
pi5ton
r

gs

Wom

pilton
ring
groove
and

ring

Fatigue
of
valve
oil
seal

lip

Worn
valv
stem

Inadequate
qUality
of

engine
oil

Engine
overheat

Exceeding
idling
revolution

Inoperative
acceleration

covel

Fuelleakage

Malfunction
of
T
O
C
S

Except
FU
mod

els

Malfunction
of

A
T
C
air
cleaner

Inadequate
oil

quality

Overheat

Worn
oil

pump
regulator
valve

Functional
deterioration
of

oil

pump

Blocked
oil
filter

Increased
clearanCe
in
various

sliding
parts

Blocked
oil

strainer

Inoperative
oil

gauge
pressure
switch

Oil

pressure
decreases

Improper
quality
or
contamination
of
oil

Damaged
air
cleaner

Overheat

or
overcool

Improper
fuel
nUxture

Decrease
of
oil

presSure

Insufficient
clearances

ET
22
Corrective
action

Overhaul

cylinder
and
renew

piston

Remount

piston
rings

Renew

rings

Repair
or
renew

piston
and

cylinder

Renew

piston
and

piston
ring

Replace
seal

lip
with

a
new
one

Renew
valve
or

guide

Us
the

designated
ou

Previously
mentioned

Adjust
it
to
the

designated
rpm

Adjust
it

Repair
or

lighten
the
connection
of
fuel

pipes

Adjust

Check
and

replace

Use
the

designated
oil

Previously
mentioned

Disassemble
oil

pump
and

repair
or
renew
it

Ref4ir
or

replace
it
with
I
new
one

Renew

i
t

Disassemble
and

replace
the
worn

parts
with

n
w

of
es

Clean
it

Replace
it
with
a
new
one

Previously
mentioned

Exchange
the
oil
with

proper
one
and

change
element

Otange
element

Previously
mentioned

Oteck
the
fuel

system

Previously
mentione
d

Readjust
to
the

designated
clearances

Page 89 of 548


TEMPERATURE
SENSOR

Removal

I

Using
pliers
flatten

clip
con

necting
vacuum

hose
to

sensor
vacuum

tube

1

Pipe

2
Catch

3
Fixed
with

adhesive

4
Hose

5
Tab

6

Clip

7
Gasket

EC019

Fig
EF
7

Removing
Seruor

2
Disconnect
hose
from

sensor

3
Take
off

clip
from
sensor
vacuum

tube
and
dismount
sensor

body
from

air
cleaner

Note

The

gasket
between

sensor
and

air

cleaner
is
bonded
to

the
air

cleaner

side
and

should
not

be

removed

Installation

Mount
sensor
on
the

specified

position

2

Insert

clip
into

vacuum
tube
of

sensor
After

installing
each
vacuum

hose

secure
hose
with
the

clip

Note
Be

sure
to
install
vacUl
11n

hose

correctly
Correct

position
is
R
H

side
to

Ntisan

mark
at
the

top

face
of
sensor
for
intake
manifold

L

H
side
for

Deuum
motor

VACUUM

MOTOR

1

Remove

screws

securing
vacuum

motor

to
air
cleaner

2

Disconnect

valve
shaft

attached

to

vacuum
motor

diaphragm
from
air

control
valve

and

remove

vacuum

motor

assembly
from
air

cleaner

3
To
install

reverse
the

removal

procedures
Engine
Fuel

Fig
EF

8
Removing
Vacuum
Motor

INSPECTION

AIR

CLEANER
FILTER

Viscous

paper

type
air

cleaner
filter

does

o
ot

rt

quire
any
cleaning
opera

tion

until
it

is

replaced
periodically

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
filter

refer
to

Maintenance

Schedule

AUTOMATIC

TEMPERATURE

CONTROL
SYSTEM

Engine
failures

resulting
from
a

malfunctioning
A
T
C

system
are

manifest

during
cold
weather

opera

tion
Such
failures

include

Engine
stall
or
hesitation

Increase
in
fuel

consumption

Lack
of

power

If
these

phenomena
should

occur

check

A
T
e

system
as

described
in

the

following
before

carrying
out

inspection
of

carburetor

I
Check
that

vacuum
hoses
are

se

l

urely
connected
in
correct

position

2

Check
each
hose

for
cracks
or

distortion

3

Check
A
T

C

system
for

proper

function
as

follo
ys
Confirm
that

engine
is

cold
before

starting
test

With

engine
topped
disconnect

fresh
air

duct
if
so

equipped

Place
a
mirror
at
the
end

of
air

cleaner
inlet

pipe
as
shown
and

check

to
see
if
air
control
valve

is
in
correct

position

EF
4
Fig
EF
9

Inspecting
Valve
Po

man

Air
control
valve
is

in
correct

posi

tion
if
its
cold
air
inlet

is

open
and

hot

air
inlet
is

closed

4
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

step
3

under

hood
air
inlet
is
closed

and
hot
air

inlet
is

open

S

Check
that
air
control
valve

grad

ually
opens
to

cold
air

inlet
side

as

engine
warms

up
When

environmental

temperature
around

temperature
sen

sor
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

opera
ion
of
air
control

valve

carry
out
the

following
test

VACUUM
MOTOR

I
With

engine
stopped
confirm

that

cold
air
inlet
is

open
and

hot
air

inlet
is

c1
Sed

If
not

check
air
control
valve
link

age
for

proper
operation

2

DiscoJln
ct
ac
um

motor
inlet

vacuum
hose

and
connect

another

hose
to
the

inlet
to

apply
vacuum
to

vacuum
motor

Vacuum
can

be

appli
d

by
breathing
in

tile
hos
e
end

as

shown
Then

confirm
that

the
air

control
valve

moves

3
With
hot
air
inlet
in

open
posi

tion
as

described
in

step
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
described
in

step
2

for
more
than

30
seconds

and

that
hot

air
inlet

is

open
If

diaphragm

spring
actuates

the
air
control
valve

by

Page 96 of 548


throttle

opener
solenoid
valve

The
throttle

opener
solenoid
valve

is

actuated
and
the

servo
diaphragm

chamber
is

opened
to
the

atmosphere

In
this
case

the
seIVo

diaphragm

does

not

opera
te
Engine
Fuel

Automatic
transmission
models

As

long
as
the

shift
lever
is
in
the

N

or
p

position
the
inhibitor

switch
on
the
transmission
is
turned

on
and
the

throttle

opener
solenoid

valve
is

actuated
Under
this
condition
the
seIVo

diaphragm
does
not

operate

because
of

the
same
reason
as
men

tioned
for
the

manual

transmission

model

ON
Car

peed
betow

t6
km
h

to

mph

OFF
Car

peed
above
16
km
h

to
mph

To
intake

manifold

j

lJl
11
1

ti

i
ljn

L

o

1

Servo

diaphragm

2

Vacuum
control
valve

3
Altitude

corrector

4
Throttle

opener
solenoid
valve

5

Inhibitor
switch
N
p

ON
for
automatic

transmission

6

Speed
detecting
switch
below

10
MPH

ON
for
manual

transmission

7

Amplifier

8

Ignition
switch

9

Primary
throttle
valve
Note

FUEL

SHUT
OFF
SYSTEM

The

fuel
shut
off

system
is

to
shut

off

the
fuel

during
deceleration

there

by

reducing
fuel

consumption
This

system
also

helps
prevent
a

tempera

ture
rise
in
the

catalytic
converter

during
long
periods
of

deceleration

The

major
parts
of
the

system
are

an
anti

dieseling
solenoid
a
neutral

detecting
switch
a

throttle
valve

switch
and

an

engine
revolution

switch
e

1

l
6

I

I

I

I

I
I

I
I

I

l

L
I

Broken
tine

applies
only
to
Automatic

Transmission
7

Anti
dieseling
solenoid

Electric
current

OFF
ON
valve

I

I

h

L

Battery

I

Neutral

detecting
switch

l

2

Throttle

valve
switch

3

Engine
revolution
switch

4

Transistor

ignition
unit
o

Ignition
switch
EF105A

Fig
EF
26
Throttle

Opener
System

ill

Ignition
coil

U
EF846

Fig
EF

27
Anti
dieseling

Solenoid
Valve

EF
11

Page 115 of 548


Engine

fuel

TROUBLE

DIAGNOSES
AND

CORRECTIONS

In
the

following
table
the

symp

toms
and
causes
of
carburetor
troubles
and
remedies
for
them
are
listed
to

facilitate

quick
repairs

There
are
various

causes
of

engine

malfunctions

It
sometimes

happens

that
a

carburetor
which
has
no
fault

appears
to
have

some

problems
when

Condition
Probable

cause

Overflow

Dirt
accumulated
on
needle
valve

Fuel

pump
pressure
too

high

Needle
valve

improperly
seated

Excessive
fuel

consumption
Fuel
overflow

Slow

jet
too

large
on
each
main

jet

Main
air

bleed

clogged

Choke
valve
does

not

open
fully

Outlet

valve
seat
of

accelerator

pump

improper

Unked

opening
of

secondary
throttle
valve

opens
ioo

early

Power

shortage
Mainjels
clogged

Every
throttle
valve
Joes

not

open

fully

Idling
adjustment
incorrect

Fuel
filter

clo
ll
ed

Vacuum

jet
clogged

Air
cleaner

clogged

Diaphragm
damaged

Power
valve

operating
improperly

Improper
idling
Slow

jet

clogged

Every
throttle
valve

does
not
close

Secondary
throttle
valve

operating
im

properly

Throttle
valve
shafts
wom

Packing
between

manifold
carburetor

faulty

Manifold
carburetor

tightening

improper

Fuel
overflow

T

O
C
S

adjustment
incorrect

Vacuum
control
solenoid

damaged

Stuck
dash

pot

EF
30
acfuaJIy
theelectric

syslem
i
at
fatilt

Therefore

whenever
the

engine
is
mal

functioning
the

electrical

system

should
be
checked

fust
before

adjust

ing
carburetor

Corrective

action

Clean
needle
valve

Repair
pump

Replace

See
above

item

Replace

Clean

Adjust

Lap

Adjust

Clean

Adjust

Repair

Repair

Clean

Clean

Replace

Adjust

Clean

Adjust

Overhaul

and
clean

Replace

Replace

packing

Correct

tightening

See
the
first

item

Adjust

Replace

Replace