DESCRIPTION
The
ignition
circuit
consists
of
igni
tion
switch
Ie
ignition
unit
dis
tributor
winng
ipark
plugs
and
battery
The
distributor
is
of
the
contactless
type
and
is
equipped
with
a
pick
up
coil
which
electrically
detects
the
igni
tion
timing
signal
in
place
of
the
ircuit
I
rea
r
of
the
conventional
distributor
The
IC
ignition
unit
is
a
new
addition
which
generates
the
signal
required
for
the
make
and
break
of
the
primary
current
for
the
ignition
coil
The
primary
current
is
supplied
by
the
battery
or
alternator
and
flows
through
the
primary
circuit
It
consists
of
the
ignition
switch
primary
winding
of
the
ignition
coil
IC
ignition
unit
and
all
connecting
low
tension
wiring
The
secondary
current
is
produced
by
the
ignition
coil
and
flows
through
the
secondary
circuit
resulting
in
high
voltage
spark
between
the
electrodes
of
the
spark
plugs
in
engine
cylinders
This
circuit
contains
the
secondary
winding
of
the
ignition
coil
distribu
tor
high
tension
cables
to
coil
and
spark
plugs
distributor
rotor
and
cap
When
the
ignition
switch
is
turned
on
and
the
distributor
reluctor
rotates
the
primary
current
flows
through
the
primary
winding
of
the
coil
and
through
IC
ignitionu
nit
to
ground
When
the
primary
circuit
is
opened
by
circuit
of
IC
ignition
unit
the
magnetic
field
built
up
in
the
primary
winding
of
the
coil
moves
through
the
secondary
winding
of
the
coil
in
ducing
high
voltage
This
high
voltage
is
produced
every
time
the
primary
circuit
opens
EngineElect
ical
System
IGNITfON
CIRCUIT
The
secondary
current
flows
through
the
high
tension
cable
to
the
distributor
cap
then
the
rotor
distributes
the
current
to
one
of
the
spark
plug
terminals
in
the
distrubutor
cap
Then
the
spark
occurs
while
the
secondary
current
jumps
the
gap
be
tween
the
insulated
electrode
and
the
ground
side
electrode
of
the
spark
plug
This
process
is
repeated
for
each
power
stroke
of
t
e
engine
The
spark
plug
should
be
inspected
cleaned
and
regapped
at
tune
up
Spark
plugs
should
also
be
replaced
periodically
as
specified
in
the
Maintenance
Schedule
The
remainder
of
the
ignition
component
parti
should
be
inspected
Battery
letink
Primary
winding
1
Ignition
coil
Secondary
winding
J
for
only
their
operation
air
gap
of
distributor
tightness
of
electrical
terminals
and
wiring
condition
Apply
grease
NLGI
consistency
No
I
containing
MaS
or
equivalent
to
distributor
rotor
shaft
as
required
WARNING
When
current
is
flowing
never
touch
with
bare
hand
high
tension
cables
or
any
other
parts
with
high
vollage
If
parts
are
moist
touching
them
could
cause
an
electric
shock
even
if
they
are
insulated
Always
wear
dry
well
insulated
gloves
or
wrap
affected
parts
with
dry
cloth
before
handling
To
starter
EE
20
Ro
or
head
Ul
J
r
Spark
plugs
EE743
Fig
EE
56
Ignition
System
Circuit
Diagram
FUSIBLE
LINK
BATTERY
VIR
9
rID
B
V
II
H
Engine
Electrical
System
1
II
1l
IGNITION
COIL
IIC
IGNITION
I
UNIT
O
J
DISTRIBUTOR
EE
21
B4J
QJ
jl
SPARK
PLUG
IGNITiON
SWITCH
EE744
Fig
EE
57
Circuit
DiGgram
of
Ignition
Sy
tem
L
Engine
E
ectrical
System
DISTRIBUTOR
CONSTRUCTION
in
place
of
the
breaker
The
amount
of
magnetic
flux
passing
through
the
pick
up
coil
is
changed
when
the
reluc
tor
rotates
and
then
the
electrical
signal
is
generated
in
the
pick
up
coil
This
electric
ignal
is
conducted
into
the
Ie
ignition
unit
which
makes
In
the
conventional
distributor
the
ignition
timing
is
detected
by
the
earn
and
breaker
arm
while
in
this
distribu
tor
it
is
detected
by
the
reluctor
on
the
shaft
and
the
pick
up
coil
provided
and
breaks
the
primary
current
run
ning
through
the
ignition
coil
and
generates
high
voltage
in
the
secondary
winding
The
centrifugal
and
vacuum
ad
vance
mechanisms
employ
the
conven
tional
mechanical
type
I
l
Q
J
1
C
@
@
ID
ID
J
I
Cap
assembly
2
Rotor
head
assembly
3
RoD
pin
4
ReluctoI
@
5
Stator
6
Magnet
assembly
7
Pick
up
coil
assembly
8
Breaker
plate
assembly
9
Rotor
shaft
assembly
10
Governor
spring
11
Governor
weight
12
Shaft
assembly
13
Housing
14
Grommet
15
Ie
igniq
n
unit
@f
rw
16
VacuwncontroUcr
17
Fixing
plate
t8
Collar
EE745
Fig
EE
58
Diatributor
EE
22
CHECKING
AND
ADJUSTMENT
CAP
AND
ROTOR
HEAD
Cap
and
rotor
head
should
be
in
spected
periodically
as
specified
in
the
Main
teoanee
Schedule
Remove
cap
and
clean
all
dust
and
carbon
deposits
from
cap
and
rotor
from
time
to
time
If
cap
is
cracked
or
is
leaking
replace
wi
th
a
new
one
ADVANCE
MECHANISMS
SpecHlcatlons
Refer
to
Service
Data
and
Specifica
tions
for
distributor
Vacuum
advance
mechanism
mechanical
parts
If
vacuum
advance
mechanism
fails
to
operate
properly
check
for
the
followin
B
items
and
correct
the
mal
function
as
required
I
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
vacuum
controUer
assembly
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
halls
or
if
necessary
replace
breaker
plate
as
an
assembly
Centrifugal
advance
mechanical
parts
When
cause
of
engine
malfunction
is
traced
to
centrifugal
advance
mecha
nical
parts
use
distributor
tester
to
check
its
characteristics
If
nothing
is
wrong
with
its
charac
teristics
conceivable
causes
are
faulty
or
abnormal
wear
of
driving
part
or
others
So
do
not
disassemble
it
In
the
event
of
improper
character
istics
check
closely
rotor
shaft
assem
bly
governor
weight
and
shaft
If
any
of
the
above
parts
are
mal
functioning
replace
the
parts
Engine
Electrical
System
DISASSEMBLY
AND
ASSEMBLY
DISASSEMBLY
I
Take
off
cap
and
remove
rotor
head
2
Remove
Ie
ignition
unit
Refer
to
IC
Ignition
Unit
for
removal
and
in
stallation
3
Remove
stator
and
magnet
by
removing
stator
securing
screws
4
Remove
vacuum
controller
by
removing
securing
screws
EE746
Fig
EE
59
Removing
Vacuum
Controller
5
Using
two
pry
bars
or
suitable
puller
pry
reluctor
from
shaft
CAUTION
When
removing
reluctor
be
careful
not
10
distort
or
damage
the
teeth
6
Remove
roll
pin
7
Remove
pick
up
coil
assembly
8
Remove
breaker
plate
setscrews
and
remove
breaker
plate
assembly
EE703
Fig
EE
60
Removing
Breaker
Plate
Setscrews
9
Punch
knock
pin
out
and
remove
pinion
EE
23
EE704
Fig
EE
61
Removing
Knock
Pin
10
Remove
rotor
shaft
and
drive
shaft
assembly
EE705
Fig
EE
62
Removing
Rotor
Shaft
and
Drive
Shaft
Assembly
11
Mark
rotor
shaft
and
drive
shaft
Remove
packing
from
the
top
of
rotor
shaft
and
unscrew
rotor
shaft
setscrew
Remove
rotor
shaft
EE706
Fig
EE
63
Removing
Rotor
Shaft
12
Mark
one
of
the
governor
springs
and
its
bracket
Also
mark
one
of
the
governor
weights
and
its
pivot
pins
13
Carerully
unhook
and
remove
governor
springs
14
Remove
governor
weights
A
r
ply
grease
to
guvernor
weights
after
disassembling
ASSEMBLY
To
assemble
reverse
the
order
of
disassembly
Carefully
observe
the
fol
lowing
instructions
CAUTION
B
tfore
installi
lg
IC
ignition
unit
make
sure
mating
surfaces
of
IC
ignition
unit
and
distriblitor
are
clean
and
free
from
dust
sand
and
moisture
Align
match
marks
so
that
parts
are
assembled
to
their
original
posi
tions
2
Ensure
that
reluctor
is
properly
oriented
when
installing
on
shaft
Al
ways
drive
in
roll
pin
with
its
slit
toward
the
outer
end
of
shaft
See
Fig
EE
64
Be
sure
to
use
a
new
roll
pin
DESCRIPTION
The
IC
ignition
unit
utilizes
a
semi
conductor
IC
device
and
is
mounted
on
the
side
surface
of
the
distributor
The
IC
ignition
unit
has
the
fol
lOwing
circuits
Spark
timing
signal
monitoring
circuit
This
circuit
detects
the
ignition
signal
sent
from
the
distributor
pick
up
coil
and
amplifies
the
signal
2
Lock
preventing
circuit
This
circuit
cuts
off
the
ignition
coil
primary
current
when
the
ignition
switch
is
ON
and
the
engine
is
sta
tionary
If
the
ignition
coil
primary
current
is
allowed
to
flow
under
such
condi
tions
excessive
current
will
be
drawn
because
of
low
internal
resistance
of
the
ignition
coil
Engine
Electrical
System
r
5
EE747
Fig
EE
64
Driuing
in
Roll
Pin
3
When
installing
pinion
on
shaft
be
sure
to
install
pinion
gear
correctly
to
position
where
it
was
installed
4
Apply
grease
to
the
top
of
rotor
shaft
as
required
5
Check
the
operation
of
governor
before
installing
distributor
on
engine
Ie
IGNITION
UNIT
This
can
result
in
an
abnormal
temperature
rise
in
the
ignition
coil
or
discharged
battery
These
malfunc
tions
can
be
prevented
by
this
lock
preventing
circuit
3
Duty
control
circuit
This
circuit
controls
the
ratio
of
the
ignition
coil
primary
current
ON
OFF
time
periods
in
one
cycle
of
ignition
operation
111is
is
equivalent
to
the
dwell
angle
of
the
conventional
point
type
dis
tributor
In
order
to
provide
high
performance
spark
ruing
over
a
wide
range
of
driving
speeds
this
duty
can
be
controlled
by
the
source
voltage
and
the
ambient
temperature
as
well
as
by
the
engine
rpm
4
Power
switching
circuit
This
circuit
is
used
to
make
or
break
directly
the
primary
circuit
cur
EE
24
6
Properly
eenterstatOr
and
reluc
tor
before
tightening
Standard
air
gap
0
3
to
0
5
mm
0
012
to
0
020
in
0
3
to
0
5
mm
0
012
to
0
020
in
Fig
EE
65
EE748
Air
Gap
7
Adjust
ignition
timing
after
distri
butor
is
installed
on
engine
rent
of
the
ignition
coil
5
Current
limiting
circuit
This
circuit
controls
the
current
value
so
that
excessive
current
will
not
flow
through
the
power
switching
cir
cuit
To
ensure
efficient
operation
of
the
IC
ignition
unit
these
five
circuits
are
manufactured
in
one
assembly
as
shown
in
Fig
EE
66
The
semi
conductor
IC
is
utilized
for
all
these
circuits
except
the
power
switching
circuit
The
power
switching
circuit
uses
one
power
transistor
and
the
circuit
is
arranged
on
the
ceramic
substrate
together
with
resislors
capa
citors
and
diodes
Each
component
part
of
this
unit
is
highly
reliable
however
should
any
part
be
found
faulty
the
entire
as
sembly
musl
be
replaced
Engine
Electrical
System
Battery
Ignition
switch
CG
1
e
@
P
L
JO
L
J
Ignition
coil
r
Spark
timing
signal
I
oni
1oring
Clfcwt
0
R
Lock
Pi
k
il
preventing
c
up
co
circuit
Ln
n
Distributor
2P
fJ
1I
connector
8C
H
uty
control
ClICUlt
Power
switching
circuit
Current
limiting
circuit
Ie
ignition
unit
EE749
Fig
EE
66
Ie
Ignition
Unit
Circuit
Diagram
REMOVAL
AND
INSTALLATION
5
Disconnect
pick
up
coil
wire
from
IC
ignition
unit
Note
Holding
connector
with
needle
nose
pliers
as
shown
in
Fig
EE
68
disconnect
pick
up
coil
terminal
Be
careful
not
to
pull
lead
wire
I
Disconnect
battery
ground
cable
2
Take
off
distributor
cap
and
re
move
rotor
head
3
Disconnect
harness
connector
4
Remove
Ie
ignition
unit
securing
screws
rf
I
I
EE751
Fig
EE
68
Di
Connecting
Pick
up
Coil
Term
inal
eE750
Fig
EE
67
Removing
Ie
Ignition
Unit
6
InstaU
IC
ignition
unit
in
the
reverse
order
of
removal
EE
25
CAUTION
Before
instelling
IC
ignition
unit
mike
sure
mlting
surfaces
of
IC
ignition
unit
end
distributor
Ire
cleen
and
free
from
dust
sand
and
moisture
Note
a
When
connecting
lead
wires
to
unit
insert
lead
wire
terminal
with
fin
ger
as
shown
in
Fig
EE
69
b
Connect
lead
wires
according
to
color
marked
on
upper
face
of
grommet
EE752
Fig
EE
69
Connecting
Pick
up
Coil
Terminal
CHECKING
IC
IGNITION
SYSTEM
DESCRIPTION
To
check
the
IC
ignition
system
use
a
circuit
tester
The
ignition
per
fannance
of
the
ignition
system
at
a
high
speed
cannot
be
measured
direct
ly
However
it
can
be
checked
by
operating
a
vehicle
actually
at
a
high
speed
The
IC
ignition
system
can
be
checked
easily
by
referring
to
the
Inspection
Table
For
the
method
of
inspection
refer
to
respective
items
INSPECTION
TABLE
I
No
spark
occur
Check
high
tension
cable
NG
OK
Repair
and
lor
replace
ngine
Electrical
System
START
Check
sparking
performance
J
J
Sparks
oci
1u
IC
IGNITION
SYSTEM
OK
Check
power
supply
circuit
NG
Repair
and
or
replace
OK
Check
primary
circuit
Proceed
to
A
Proceed
to
A
NG
epair
an
or
replace
OK
Proceed
to
A
DISTRIBUTOR
ASSEMBLY
NG
lC
IGNITION
UNIT
AND
OR
PICK
UP
COIL
NG
Mealure
pick
up
coil
resistance
as
a
distributor
assembly
Except
approx
4000
Measure
igilition
coii
8terminalvoltage
Battery
voltage
t
OV
Measure
pick
up
coil
resistance
I
Ie
IGNITION
UNIT
NG
Except
approx
400n
Approx
400n
PICK
UP
COIL
NG
1
PICK
UP
COIL
OK
Replace
IC
IGNITION
Replace
I
UNI
NG
l
Meuure
pick
up
coil
resistance
Except
approx
4000
I
Check
sparking
performance
I
Replace
I
r
PICK
UP
COIL
NG
1
No
spark
occun
Sparks
occur
I
IC
IGNITION
flc
IGNITION
Proceed
to
A
Replace
UNIT
NG
i
UNIT
OK
Proceed
to
A
Replace
Proceed
to
A
CHECKING
PROCEDURE
Sparking
performance
check
L
Turn
ignition
switch
to
OFF
position
2
Disconnect
anti
dieseling
solenoid
valve
connector
to
cut
off
supply
of
fuel
to
engine
3
Disconnect
high
tension
cable
from
spark
plug
4
Keeping
high
tension
cable
end
4
to
5
mm
0
16
to
0
20
in
away
from
engine
block
rotate
starter
motor
and
check
whether
sparks
occur
across
the
clearance
JUDGMENT
Sparks
occur
IC
ignition
system
OK
In
this
case
IC
ignition
system
and
component
parts
need
not
be
checked
beyond
this
No
spark
occurs
IC
ignition
system
NG
In
case
of
NG
check
High
Tension
Cables
Nole
This
check
is
designed
to
deter
mine
only
ignition
spark
perform
ance
when
cranking
engine
If
test
results
are
satisfactory
Ibis
does
EE
26
I
Approx
400n
PICK
UP
COIL
OK
1C
IGNITION
UNIT
NG
I
Repair
and
or
replace
I
Proceed
to
A
Approx
400n
l
PICK
UP
COIL
OK
1
not
alwaY
indicate
performance
sufrlcienl
for
high
speed
operation
IOgh
tension
cable
check
Refer
to
Engine
Tune
up
for
Check
ing
Ignition
Wiring
Distributor
Cap
and
Rotor
JUDGMENT
If
high
tension
cable
is
OK
check
Power
SupplY
Circuit
If
high
tension
cable
is
NG
replace
cable
assembly
Power
suppl
circuit
check
Make
sure
that
ignition
switch
is
in
OFF
position
2
Disconnect
Ie
ignition
unit
con
nector
from
unit
3
Turn
ignition
switch
to
ON
position
4
Measure
voltage
at
the
terminal
as
shown
in
Fig
EE
70
I
I
1
Fig
EE
70
EE734
Checking
Power
Supply
Circuit
5
Turn
ignition
switch
to
OFF
position
JUDGMENT
Battery
voltage
is
indicated
OK
In
this
case
check
Primary
Circuit
Battery
voltage
is
not
indicated
NG
In
case
of
NG
check
power
supply
wirings
fusible
link
ignition
switch
and
connecto
s
for
condition
and
con
tinuity
Primer
circuit
check
I
Make
sure
that
ignition
switch
is
in
0
FF
position
2
Disconnect
IC
ignition
unit
con
nector
from
unit
3
Turn
ignition
switch
to
ON
position
4
Measure
voltage
at
the
terminal
as
shown
in
Fig
EE
7I
1
I
r
1
EE735
Fig
EE
7I
Checking
Primary
Circuit
Engine
Electrical
System
5
Turn
ignition
switch
to
OFF
position
JUDGMENT
Battery
voltage
is
indicated
OK
In
this
case
proceed
to
the
step
for
IC
Ignition
Unit
and
Pick
up
Coil
Check
Battery
voltage
is
not
indicated
NG
If
NG
check
condition
and
con
tinuity
of
primary
circuit
wirings
and
connectors
If
results
of
these
inspec
tions
are
satisfactory
check
Ignition
Coil
Ignition
coil
check
I
Make
sure
that
ignition
switch
is
in
OFF
position
2
Disconnect
harness
connector
from
ignition
coil8terminal
3
Measure
resistance
between
and
8terminals
Resistance
1
range
C2J
j
EE567
Fig
EE
72
Checking
Ignition
Coil
Assem
bly
JUDGMENT
If
resistance
value
is
0
84
to
1
02n
OK
If
resistance
value
is
other
than
the
specified
value
NG
Ie
Ignition
unit
end
pick
up
coli
check
If
power
supply
circuit
primary
circuit
and
high
tension
cables
are
in
good
order
IC
ignition
unit
and
or
pick
up
coil
are
malfunctioning
I
Make
sure
that
ignition
switch
is
in
OFF
position
2
Remove
distributor
cap
and
ro
tor
EE
27
3
Measure
resistance
between
two
terminals
of
pick
up
coil
as
a
distribu
tor
assembly
with
a
circuit
tester
1
Tester
probes
2
Grommet
3
Ie
ignition
urnt
EE736
Fig
EE
73
Measuring
Pick
up
Coil
Resistance
4
Measure
resistance
by
reversing
polarity
of
circuit
tester
probes
JUDGMENT
Approx
400n
are
indicated
Pick
up
coil
OK
IC
ignition
unit
NG
In
this
case
replace
faulty
IC
igni
tion
unit
with
new
one
Approx
400n
are
not
indicated
Condition
cannot
be
judged
Thus
proceed
to
item
5
Note
If
resistance
is
approx
4OOn
no
further
inspection
is
required
replace
IC
ignition
unit
5
Make
sure
2
pin
IC
ignition
unit
connector
is
securely
connected
to
unit
6
Turn
ignition
switch
to
ON
position
7
Measure
voltage
at
ignition
coil
8
terminal
8
Turn
ignition
switch
to
OFF
position
CAUTION
Turn
ignition
switch
off
after
releasing
test
probe
of
circuit
tester
from
nega
tive
terminal
of
ignition
coil
Failure
to
do
this
could
result
in
damage
to
circuit
tester