spark plugs replace DATSUN B110 1973 Service Repair Manual

Page 309 of 513


ENGINE

Checking

cooling
system
hoses

and
connections

Check

cooling
system
hoses

and

fiHings
for
loose

connections
and
deterioration

Retighten
or

replace
as

necessary

Inspection
of
radiator

cap

Apply
reference

pressure
0
9

kg
cm1
13

psi
to

radiator

cap
by
means
of
a

cap
tester
to

see
if
it
is
in

good
condition

Replace
cap
assembly
if

necessary

ET012

Fig
ET
5

Testing
radiator

cap

Cooling
system

pressure
test

With
radiator

cap
removed

apply
reference

pressure

1
6

kg
cm1
23

psi
to
the

cooling

system
bv
means

of
a

tester
to
check

for
leaks

at
the

system
compo

nents

Water

capacity

with
heater

4
9
l
I
Y
US

gal
l
i

Imp
gal

without
heater
4
2

l

I
i
US

gal
i

Imp
gal

Fig
ET
6

Testing
cooling
system
pressure
Checking
vaccum

fittings
hoses

and
connections

Check
vacuum

system
fittings
and
hoses
for

loose

connections
and

deterioration

Retighten
if

necessary

replace
any
deteriorated

parts

Checking

engine
compression

Compression
pressure
test

Note
To
test

cylinder

compression
remove
all

spark

plugs
and
hold
tester

fitting
tightly
in

spark
plug

hole
of

cylinder

The

tester
is
used
to

determine
whether

cylinder

can
hold

compression
or
whether
there
is

excessive

leakage

past
rings
etc

I

Td10

l
y

Fig
ET

7

Testing

compression
pressure

Test

compression
with

engine
warm
all

spark
plugs

removed
and
throttle
and
choke
valve

opened
No

cylinder

compression
should
be
less

than
80

of

highest
cylinder
s
Excessive
variation

between

cyl

inders

accompanied
by
low

speed
missing
of
the

cylinder
usually
indicates
a

valve
not

properly
seating

or
a
broken

piston
ring
Low

pressures
even

though

uniform

may
indicate
worn

rings
This

may
be

accompanied
by
excessive

oil

consumption

Test

conclusion

If
one
or
more

cylinders
read
low

inject
about
one

tablespoon
of

enigne
oil
on

top
of
the

pistons
in
low

ET
4

Page 311 of 513


ENGINE

4
Install

a

timing
light
on
No

cylinder
spark

plug

wire
and
install

a
tachometer

5

Set

idling
speed
to

approximately
800

rpm

6

Check

ignition
timing
if

it
is
50BTDC
Before

Top
of

Dead
Center

by
the

use
of

timing
light

If

necessary
adjust
it

as
follows

Loosen
set
screw
to
such
an
extent
that

distributor
can

be
moved

by
hand

2

Adjust
ignition
timing
to
50BTDC

3

Lock
distributor

set
screw
and
make
sure
that

timing

is
correct

Fig
ET
9

Checking
ignition
timing

Ignition
timing
degree
50
B
T
D
C

Checking
or

replacing
distributor

breaker

point
condenser
and

spark

plugs

Distributor
breaker

point

Check
distributot
breaker

points
for
abnormal

pitting

and
wear

Replace
if

necessary
Make
sure

they
are
in

correct

alignment
for
full
contact
and
that

point
dwell

and

gap
are
correct
Clean
and

apply
distributor

grease

to
earn
and
wick

Note
Do
not

apply
grease
excessively
Distributor

Point

gap
0
45
to
0
55
mm

0
018

to
0
Q22
in

49
to
55

degrees
Dwell

angle

ET004

Fig
ET
10

Checking
distributor

point
gap

Condenser

I

Clean
outlet
of
condenser
lead

wire
and
check
for

loose

set
screw

Retighten
if

necessary

2

Check
condenser

capacity
with
a

capacity
meter

Condenser
insulation
resistance

may
be
also
checked

using
a

tester

by
adjusting
its

range
to
measure

large

resistance
value
When
condenser
is
normal
the

tester

pointer
swings
largely
and

rapidly
and
moves

gradually

back

to
the

infmite
side
When
the

pointet
does

not

stay
still
or
it

points
zero
in
resistance

replacement
is

necessary

Condenser

capacity

0

221LF
Micro
Farad

Condenser
insulation
resistance

5
Mn

Mega
ohms

Spark

plugs

Remove

and
clean

plugs
in

a
sand
blast
cleaner

Inspect

each

spark
plug
Make
sure
that

they
are
of
the

specified
heat

tange
Inspect
insulator
for
cracks
and

chips
Check

both
center
and

ground
electrodes
If

they
are

excessi
ely
worn

replace
with
new

spark

plugs
File
center
electrode
flat

Set
the

gap
to
0
8
to

0

9
rom
0

031
to
0
035
in

using
the

proper

adjusting

tool

Tighten
plugs
to

1
5
to
2
0

kg
m
11
0
to
15
0

ft

lb

torque

ET
6

Page 312 of 513


EMISSION
CONTROL
AND

TUNE
UP

Fig
ET
11

Checking
spark
plug
gap

Checking
distributor

ignition
wiring

and

ignition
coil

Distributor

Check

centrifugal
advance
unit
for
loose
connection

or

improper
operation

If
it
is
not

operating

properly
the
trouble

may
be
due

to
a

sticky
spring
or

excessively
worn

parts

This

operation
needs
a
distributor
tester
As
to

inspection
procedure
and
reference
data
refer

to

relative

topic
under
Distributor
in
Section
EE

Page

EE
32

If
vacuum
advance
mechanism
fails
to

operate

proJr

erly
check
for
the

following
items
and
correct
the

trouble
as

required

1

Check
vacuum
inlet
for

signs
of

leakage
at
its

connection
If

necessary
retighten
or

replace
with
a

new
one

2

Check
vacuum

diaphragm
for
air
leak

If
leak
is

found
replace

diaphragm
with
a

new
one

3

Inspect
breaker

plate
for
smooth

moving

If

plate
does
not
move
smoothly
this
condition
could

be
due
to

sticky
steel
balls
or

pivot

Apply
grease
to
steel
balls
or

if

necessary
replace

breaker

plate
as
an

assembly

For
vacuum
advance
characteristics
refer
to
Distribu

tor
in

Section
EE

Page
EE
32

Ignition
wiring

Use
an
ohmmeter
to
check
resistance
of
secondary

cables
Disconnect
cables
from

spark
plugs
and
install

the

proper
adapter
between
cable
and

spark
plug
Remove

distributor
cap
from
the
distributor

with

secondary
cables
attached
Do
not
remove
the
cables

from
the

cap

Check
the
resistance
of
one

cable
at
a
time

Connect
the
ohmmeter
between

the

spark
plug
adapter

and

the

corresponding
electrode

inside
the

cap
If

resistance
is

more
than
30

000
ohms
remove
the
cable

from
the

cap
and
check
cable
resistance

only
If
the

resistance
is
still

more
than
30
000
ohms
replace
cable

assembly

T

I

II

Fig
ET
12

Checking
high
tension
cables

Ignition
coil

Check

ignition
coil

for

appearance
oil

leakage
or

performance
For
details
refer
to
Section
EE

Page

EE36

Checking
distributor

cap
and
rotor

Note
This

operation
is
to
be

performed
while

chekcing

distribuotr

points
Inspect
distributor

cap
for

cracks
and
flash
over

External
surfaces
of
all

parts
of

secondary
system
must

be
cleaned
to
reduce

possibility
of

voltage
loss
All
wires

should
be
removed
from
distributor
cap
and
coil

so
that

terminals
can
be

inspected
and
cleaned
Burned
or

corroded
terminals
indicate
that
wires
were
not

fully

seated
which

causes
arcing
between
end
of
wire

and

terminal
When

replacing
wires
in

terminal
be
sure

they

are

fully
seated
before

pushing
rubber

nipple
down
over

tower

Check
distributor
rotor
for

damage
and
distributor

cap
for
cracks

ET
7

Page 331 of 513


ENGINE

Spark
plugs

Cap
mm
in
0
8
to
0
9
0
03110
0
035

Idle
CO
ldie

speed

Manual
transmission

rpm

rpm
1
5

to
5
800

1
5
to
5

650
in
D

position
Automatic
transmission

Dash

pot

Setting

engine
speed

rpm
1
900

to
2
000

Throttle

opener
at
sea
level

Setting
vacuwn

pressure

Manual
transmission

Automatic
transmission

Setting

engine
speed
no
load

Servo

diaphragm
full
stroke
rpm

mm
in
500
to
540
19
7

to
21
3

480
to
520

18
9
to
20
5

1
650
to
1
850

5
0
1969
mmHg
in
Hg

mmHg
in
Hg

Theono
switch
Temperature
rises

from
low
to

high
oC
0

F
above
5

41

Flow

guide
valve

Opera
ting

pressure
mmHg
in

Hg
10
0
4

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Troubles
Possible
causes
Remedies

CANNOT
CRANK

ENGINE
OR
SLOW

CRANKING
Improper
grade
oiL
Replace
with

proper
grade
oiL

Discharged
battery
Charge
battery

Defective

battery
Replace

Loosen
fan
belt
Adjust

Trouble
in

charge
system
Inspect
charge
system

Wiring
connection
trouble
in

starting
circuit
Correct

Defective
starter
switch
Repair
or

replace

Defective
starter
motor
Repair
or

replace

ET
26

I

Page 334 of 513


IMPROPER
ENGINE

IDLING

Fuel

system
in

trouble

Low

compression

Others

Ignition
system
in
trouble

Engine
idle
too
fa
t

ENGINE
POWER
NOT

UP
TO
NORMAL

4
w

compression

Ignition

system
in

trouble

Fuel

system
in
trouble
EMISSION
CONTROL
AND
TUNE
UP

Clogged
or

damaged
carburetor

jets

Incorrect

carburetor

adjustment
idle

speed

idle
mixture

Clogged
air

cleaner

Defective

gaskets
of
manifolds
or

carburetor

insulator

Improper
float
level

adjustment

Incorrect
valve
clearance

Extremely
low
revolution

Incorrect
basic

ignition
timing

Incorrect
automatic

teinperature
control
air

cleaner

Defect
or
malfunction
of

ignition
system

spark
plug
high
tension
cable
breaker

point
ignition
coil
etc

Trouble
in
throttle
link
and
cable

Incorrect
throttle

opener

adjustment

Trouble
in

PCV
valve

Trouble
in
automatic

choke

Defect

or
malfunction
of

ignition
system

spark
plug
high
tension
cable

breaker

point
ignition
coil
etc

Incorrect

ignition
timing

Defective

spark
plugs

Defective
distributor

points

Malfunction
of
choke

system

Clogged
fuel

pipe

ET
29
Clean
or

replace

Adjust
idle

speed
mixture

Replace
element

Replace

gasket

Adjust

Previously
mentioned

Adjust

Adjust
idie

rpm

Adjust
ignition
timing

Adjust
automatic

temperature
control

air
cleaner

Adjust
or

replace
ignition
system

Check
throttle
link
and
cable

Adjust
throttle

opener

Replace
PCV
valve

Adjust
automatic
choke

Adjust
or

replace

ignition
system

Previously
mentioned

Adjust

Clean

adjust
or

replace
plugs

Dress
or

replace
points
Check
con

denser

Adjust

Clean

Page 337 of 513


ABNORMAL

COMBUSTION

backfire
afterflfe

run
on
etc

Improper
ignition
timing

Fuel

system
in
trouble

Defective

cylinder
head

etc

EXCESSIVE
OIL

CONSUMPTION

Oil

leakage

Excessive
oil

consumption
ENGINE

Improper
ignition
timing

Improper
heat

range
of

the

spark
plugs

Damaged
carburetor
or
manifold

gasket

backfire
afterflre

Defective
carburetor

jet

Improper
function
of
the
float

Uneven

idling

Improperly
adjusted
valve
clearance

Excess
carbon
in
the
combustion
chamber

Damaged
valve

spring
backfire
afterure

Loose
oil
drain

plug

Loose

or

damaged
oil

pan
gasket

Loose
or

damaged
chain
cover

gasket

Defective
oil
seals
in
front
and

rear
of
the

crankshaft

Loose
or

damaged
locker

cover
gasket

Improper
tightening
of
oil
filter

Loose
or

damaged
oil

pressure
switch

Worn

cylinder
and

piston

Improper
location
of
the

ring
split
or
reo

versed

assembly

ET
32
Adjust
the

ignition
timing

Use

specified
spark
plugs

Replace
them
with
new
ones

Disassemble
the
carburetor
and

check

it

Adjust
the
level
and

check
the
needle

valve

Adjust

Readjust

Remove
the

cylinder
head
and

remove

carbon

Replace
it
with

a
new
one

Tighten
it

Renew
the

gasket
or

tighten
it

Renew
the

gasket
or

tighten
it

Renew
the
oil

seals

Renew
the

gasket
or

tighten
it

Do
not

tighten
excessively

Renew
the

gasket
and

tighten
it
cor

rectly

Retighten
or
renew

the
oil

pressure

switch

Overhaul
the

cylinder
and
renew
the

piston

Reassemble
the

piston
rings
correctly

Page 457 of 513


ENGINE
ElECTRICAL
SYSTEM

SPECIFICATIONS

Make
and

type

Primary
voltage
v

Spark

gap
mm
in

Primary
resistance

at
200C
680

F
n

Secondary
resistance

at
200C
680F
Kn

External
resistor

at
200C
680
F
n

Applied
resistor
HANSHIN
HITACHI

H5
15
2
C6R
601

12
12

more
than
7

more
than
7

0
28
0
28

1
17
to
I
43
l
l
7

to
I
43

11
2
to
16
8
11
2

to
16
8

l
3tol7
l
3tol7

RC
15
5560R
151O

SPARK
PLUG

CONTENTS

DESCRIPTION

INSPECTION

CLEANING
AND

REGAP
EE
37

EE
37

EE
38

DESCRIPTION

The

spark
plugs
are
of
the
resister

type
having
14
mm

0
551
in
threads
and
0
8
to
0
9
mm
0
031
to
0
Q35
in

gap

Note
All

spark
plugs
installed
on
an

engine
must

be
of

the

same
brand
and
number
of
heat

range

INSPECTION

1
Remove

spark
plug
wire

by
pulling
on
boot
not
on

wire
itself

2
Remove

spark
plugs

3

Check
electrodes
and
inner
and
outer

porcelains
of

plugs
noting
the

type
of

deposits
and
the

degree
of

electrode
erosion

Refer
to

Figure
EE
74

Normal
Brown

to

grayish
tan

deposits
and

slight
elec

trode
wear
indicate
correct

spark

plug
heat

range
SPECIFICATIONS
AND

SERVICE
DATA

TROUBLE

DIAGNOSES
AND

CORRECTIONS
EE
38

EE
39

Carbon
fouled

Dry
fluffy
carbon

deposits
on
the

insula

tor
and

electrode
were

mostly
caused

by
slow

speed

driving
in

city
weak

ignition
too
rich
fuel
mixture

dirty
air

cleaner
etc

H
is

advisable
to

replace
with

plugs
having
hotter
heat

range

Oil
fouled
Wet

black

deposits
show

excessive
oil

en

trance
into
combustion

chamber

through
worn

rings

and

pistons
or
excessive

clearance
between

valve

guides

and

stems
If
the
same

condition
remains

after

repair

use
a

hotter

plug

Overheating
White
or

light
gray
insulator
with
black

or

gray
brown

spots
and

bluish
burnt
electrodes
indicate

engine

overheating
Moreover
the

appearance
results

from
incorrect

ignition
timing
loose

spark
plugs
low

fuel

pump
pressure
wrong
selection

of
fuel
a

hotter

plug
etc

H
is
advisable
to

replace
with

plugs
having
colder

heat

range

EE
37

Page 459 of 513


ENGINE
ELECTRICAL
SYSTEM

TROUBLE
DIAGNOSES

AND

CORRECTIONS

When

engine
does
not

start

If
there
is
no
trouble
in
fuel

system

ignition
system

should
be
checked
This
can
be

easily
done

by
detaching
a

high
tension
cable
from

spark
plug
starting
engine
and
observing
condition
of

spark
that
occurs
between

high

tension

cable
and

spark
plug
terminal
After

checking
this

repair
as

necessary

Length
of

Trouble
location
Cause
Remedies

spark
gap

No

sparks
at
all
Distributor

Defective
insulation
of
condenser

Replace

Breakage
of
lead
wire
on
low
tension
side

Repair

Defective
insulation
of

cap
and

rotor
head

Replace

Point
does

not

open
or
close

Repair

Ignition
coil
Wire

breakage
or
short
circuit

of
coil

Replace
with
new

one

High
tension
cable
Wire

coming
off

Repair

Defective
insulation

Replace

I

to
2
mm

0
0394
Distributor
Point

gap
too
wide

Correct

to
0
0787
in

or

Oil

sticking
on

point
Clean

irregular

Point
burnt

too
much

Replace

Less
than
6

mm
Spark
plugs
Electrode

gap
too
wide
Correct
or

replace

0
2362
in

Too

much
carbon
Clean
or

replace

Broken
neck
of
insulator

Replace

Expiry
of

plug
life

Replace

2

When

engine
rotates
but
does

not
run

smoothly

In

this
case
there

are

many
causes
resulting
from
the

ignition
system
and

other

engine
conditions

not
related
to
ignition
Therefore
first

complete

inspection
of

ignition

system
should
be
carried
out

EE
39

Page 460 of 513


Troubles

Engine
misses

Engine
causes

knocking
very

often

Engine
does

not

give
enough

power
Trouble
location

Distributor

Ignition
coil

High
tension
code

Spark
plugs

Distributor

Spark
plugs

Distributor

Spark
plugs
ENGINE

Causes

Dirty
point

Improper
point
gap

Leak

of

electricity
of

cap
and
rotor
head

Defective
insulation
of
condenser

Defective
arm

Defective

spring
of
arm

Breakage
oflead
wire

Worn

out
or

shaky
breaker

plate

Worn
out
or

shaky
distributor
shaft

Layer
short

circuit
or
use
of

inferior

quality

Deterioration
of

insulation
and
leak

of

electricity

Dirty

Leak
of

electricity
at

upper
porcelain
insu

lator

Improper
and
advance

timing

Coming
off
or

breakage
of

governor
spring

A

pin
or
a

hole
of

governor
portion
worn

out

Burnt
too
much

Improper
and
retarded

timing

Defedive
function
of

governor

Dirty
point

Point

gap
too
narrow

Dirty

EE
40
Remedies

Clean

Correct

Repair
or

replace

Replace

Oil
shaft

Replace
assembly

Replace

Replace
assembly

Replace
assembly

Replace
with

good

one

Replace

Clean

Repair
or

replace

Correct
the

fitting

Correct
or

replace

Replace

Replace

Correct
the

fitting

Replace
assembly

Clean

Correct

Clean