1973 DATSUN B110 Service Repair Manual

Magnetic
switch

operating
sound
is

heard

The

starting
motor

rotates

Pinion

gear
does

not

intermesh
with

ring

gear
ENGINE
ELECTRICAL
SYSTEM

Starter

Magnetic
switch

Battery

Wiring

Starting
motor

Magnetic
switch

Ring
gear

Starting
motor
Broken
armature
or
field
coil
cable

Broken
brush

pig
tail

Defective
mica

Broken
or
shorted
series
coil

Faulty
plunger
sliding

Over

discharging

Faulty
terminal

contact
or
loose

connection

Faulty
B
or
M
terminal
connections

Shorted
armature
or
field
coil

Worn

brush
or

improper
spring

pressure

Contaminated
commutator
or
de

fective
mica

Faulty
brush
connection

Seized
metal

Armature
contacted
with

pole
core

Insufficient
plunger
L

dimension

Faulty
contact

Broken
or

shorted
shunt
coil
wire

Worn
teeth

Weakened

pinion
sleeve

spring

Worn

pinion
teeth

EE

13
Replace

Replace

Correct
or

replace

Replace

Repair
or

replace

Measure

specific

gravity

of

electrolyte
arid

charge
if

necessary

Clean
and

retighten

Retighten

Repair
or

replace

Repair
or

replace

Clean
or

repair

Repair

Replace

Repair
or

replace

Adjust

Replace

Replace

Replace

Replace

Replace

Pinion
intermeshes

with

ring
gear

Starting
motor

rotates

and

pinion
intermeshes

with

ring
gear
but
ro

tation
is

too
slow

When

starting
switch
is

set
to
OFF
the
start

ing
motor
does
not

stop
Starting
motor

Battery

Wiring

Ignition
switch

Starting
motor

Ignition
switch

Magnetic
switch

Starting
motor
ENGINE

Faulty
pinion
sliding

Dropped
off
lever

pin

Excessive

plunger
L
dimension

Defective

over

running
clutch

Over

discharging

Improper
or
loose
terminal
contact

Improperly
tightened
connection

Rough
contact
surface

Shorted
armature
coil
or
field
coil

Worn
brush
or
insufficient

spring

pressure

Contaminated
commutator
or
im

proper
brush
contact

Defective
mica

Lack
of
metal
lubrication

Armature

contacted
with

pole
core

Faulty
returning

Seized
contact

Shorted
coil

Faulty

plunger
sliding

Pinion
does
not

disengage
from
the

ring
gear
smoothly

Pinion

spline
does
not

disengage

smoothly

Seized

pinion
metal

EE
14
Repair

Repair

Adjust

Replace

Charge
battery

Repair
and

retighten

Retighten

Repair
or

replace

Repair
or

replace

Repair
or

replace

Repair

Repair

Repair
or

replace

Repair
or

replace

Replace

Replace

Replace

Replace

Repair
or

replace

Repair
or

replace

Replace

ENGINE
ElECTRICAL

SYSTEM

CHARGING
CIRCUIT

IGNITION

1

i
n

ITCH

r
B

i
i

vel

oU

ARMATURE

lip
J

l
t

lJ

FIEL

Df

e
I
I
3
2

I

u
P

5
0

IL
U
p

P
f

H
i

I

I

L

J

L
J

ALTERNATOR

VOL
TAGE

REGULATOR
The

charging
circuit

consists
of
the

battery
alternator

regulator
and

necessary
wiring
to
connect

these

parts
The

purpose
of
this

system
is
to
convert

mechanical

energy

from
the

engine
into

electrical

energy
which

is
used
to

operate
all

electrically
operated
units
and
to

keep
the

battery
fully
charged

When
the

ignition
switch
is

set
to
on

current
flows

from
the

battery
to

ground
through
the

ignition
switch

voltage

regulator
IG
terminal

primary
side
contact

point

PI

movable

contact

point
P2

voltage
regulator
F

terminal
alternator
F
terminal

field
coil
and
alternator

E

terminal
as
shown
in

Figure
EE
27

by
full

line
arrow

marks
Then

the
rotor
in
the
alternator
is
exited
On
the

other

hand
current
flows
from
the

battery
to

ground

through
the

ignition
switch

warning
lamp
voltage
regu

lator
L
terminal

lamp
side

contact

point
P4

movable
contact

point
PS
and

voltage

regulator
E

terminal
as
shown

by
dotted
line

arrow
marks
Then
the

warning
lamp
ligh
ts

When
the

alternator

begins
to

operate
three

phase

alternating
current
is

induced
in
the

armature
This

alternating
current
is

rectified

by
the

positive
and

negative

silicon

diodes
The

rectified
direct
current

output
reaches

the
alternator
A
and

E
terminals

On

the
other
hand
the
neutral

point
voltage
reaches

N
and
E

terminals

nearly
a

half
of
the

output

voltage
and

current
flows

from

voltage
regulator
N

terminal
to
E

terminal
or

ground
through
the
coil
VCI
as
shown
in

Figure
EE

28

by
the
dolled

line

arrow

marks
Then
the

coil
vc
I
is

excited
and
the

movable

contact

point
P5

comes
into
contact

with

voltage

winding
side
contact

point
P6
This
action

causes
to

turn
off
the

warning
lamp
and

complete
the

voltage

winding
circuit
as

shown

by
the
ullline
arrow
marks

When
the

alternator

speed
is
increased
or

the

voltage

starts
to
rise

excessively
the
movable
contact

point
P2

is

separated
from

the

primary
side
contact
P

1

by
the

magnetic
force
of

coil
V2

Therefore

register
RI
is

applied
into
the
field
circuit

and

output
voltage
is

decreased
As
the

outpu
t

voltage
is

decreased
the

movable

contact

point
P2

and

primary
side

contact
PI
comes

into

contact
once

again
and

the
alternator

voltage

increases

Thus
the

rapid
vibration

of
the

movable

contact

point
P2
maintains
an

alternator

output

voltage
to
constant

When
the

alternator

speed
is

further
increased
or
the

voltage
starts
to
rise

excessively
the

movable
contact

point

P2

comes
into
contact
with

secondary
side

contact

point
finally
Then
the

field
current
is
shut
off
and

alternator

output
voltage
is
decreased

immediately
This

action

causes
to

separate
movable
contact
P2
from

secondary
contact
P3

Thus
the

rapid
vibration
of
the

movable
contact

point
P2
or

breaking
and

completing

the
field
circuit
maintains
an
alternator

output
voltage
to

constant

j

T
SA

TIERY

I

l

e

7

Fig
EE
27

ChaTging
ciTcuit
1

EE
15

ENGINE

r

Ignition
switJ

c
o

iArm
ture

j

i
i
VC2
P

tP2
d

I
I

I

PI

I

ll
Rl

L

I
I

lRJ
t

R
I

Field

e
I

I

I
I

Ps
I

1
I
I

n
I

coil

M
4

i

f
I

L
1
J

Alternator

Voltage
regulator

Fig
EE
2B

ChaTging
ciTcuit
II

ALTERNATOR

CONTENTS

DESCRIPTION

REMOVAL

DISASSEMBL
Y

INSPECTION
AND
REPAIR

Rotor

inspection

Inspection
of

stator

I

nspection
of
diode
EE
16

EE
17

EE
17

EE
19

EE

19

EE
19

EE
20

DESCRIPTION

In
the
alternator

a

magnetic
field
is

produced
by
the

rotor

which
consists

of
alternator
shaft
field
coil

pole

pieces
and

slip
rings
The

slip
rings
pressed
in
the

shaft

conduct
only
a
small
field
current

Output
current
is

generated
in
the
armature

coils
located
in
the
stator

The

stator
has
three

windings
and

generates
three

phase

alternating
currenl

Silicon
diudes
act
like
a

one

way
valve

for

electricity
so
that

charging
currcnt

passes
easily
but

reverse

current
is

shut
out
In

this
alternator
six
diodes
0

E
0

c

co

0

E
c

o

0

c

Cl
Battery

T

e

I

nspection
of
brush

Spring
pressure
test

REASSEMBL
Y

ALTERNATOR
TEST

SPECIFICATIONS
AND
SERVICE
DATA

Specifications

Service
data
EE
20

EE
21

EE
21

EE
21

EE
22

EE
22

EE
22

are
used

three

negatives
and
three

positives
Positive

plate
has
three

positive
diodes
and

negative
plate
has
three

negative
diodes
and

are
installed
in

positive
and

negative

plates
as
an

assembly

Pack

type
silicone
diodes
are
used
in
this

alternator

These
diodes

are

direct
soldered
at
their

tips
and

con

structed
with

positive
and

negative

conjunction
They
are

mounted
on

the
two

plates
which
combine
the

function

of
heat

dissipating
plate
and

positive
negative
terminals

and
are

light
in

weight
and

easy
to

service

EE

16

ENGINE
ElECTRICAL
SYSTEM

CD
@

@
@

y

@
1

Pulley
assembly

2

Front
cover

3

Front

bearing

4

Rotor

5
Rear

bearing

6
Stator

7
Rear
cover

8
Brush

assembly

9
Diode
set

pl
te

assembly

10
Diode

cover

Jl

Through
bolt

EE031

Fig
EE
29

Exploded
view

of
altematoT

REMOVAL

3

Loosen
the

adjusting
bolt

@
o

lL
1
Disconnect
the

negative
battery
terminal

2
Disconnect

two
lead
wires

and
connector
from
the

alternator

4
Remove
the
alternator

drive
belt
@

J

5
Remove
the
alternator
installation
bolt

@@@

6
Dismount
the

alternator
from
the
vehicle

EE033

Fig
EE
JO
Removal

of
pulley

DISASSEMBLY

l
Remove
the

pulley
nut

pulley
rim
fan
and
the

spacer
the

brush
holder
cover
Remove

the
brush
holder
forward

and
remove
the
brushes

together
with
the
brush

holder

2
Remove
the
brush
holder

fixing
screws
and
remove
Note
Do
not
disconnect
N
term
inal
from
stator
coil
lead

wire

EE
17

ENGINE

G

2

3
N

terminal

Brush
holder

Brush
holder
cover
@

f

fI

0

EE034

Fig
EE
31
Removal

of
brush

3
Loosen
and
remove
three

through
bolts

Separate
the

diode
end

housing
from
the
drive
end

housing
assembly

by
tapping
the
front
bracket

lightly
with
a
wooden
mallet

1

L

c

EE035

Fig
EE

32
Separating

front
cover
with
Totor

from
rear
cover

4

Remove
three
screws
from
the

bearing
retainer

and

separate
the

rotor
from
the
front
cover

L1

1

t

DO

L
EE036

Fig
EE
33
Removal

of
TOtOT
5
Pull
out
the
rear

bearing
from
the
rotor

assembly

with
a

press
or

bearing

puller

I

I

l

I

EE037

Fig
EE
34

Pulling
out

of
TeaT

bearing
I

j

EE038

Fig
EE
35

Pulling
out

of
Tear

bearing
II

6
Remove
the

diode
cover
fIxing
screw
and
remove
the

diode
cover
Disconnect
three
stator
coil
lead
wires

from

the
diode
terminal
with
a

soldering
iron

7

Remove
the
A
terminal
nut
and
diode
installation

nut
and
remove
the
diode

assembly

Diode

assembly

I

o

@

Diode
cover

rJ
0
00

@

Y

o@

o

EE039

Fig
EE
36

Removing
diode

assembly

EE
18

ENGINE

ELECTRICAL
SYSTEM

Note
Use
care
in

handling
diode

assembly
to

prevent
an

undue
stress
on

it

INSPECTION
AND
REPAIR

Remove
the

alternator

from
the
vehicle
and

apply
the

tester
between
the

lead
wire
F
white
with

black

tracer

and

the
lead
wire
E

black
color
When
the

resistance
is

approximately
511
the
condition
of

brush
and
field

coil
is

satisfactory
When
no

conduction
exists

in
the
brush

field

coil
or
when
resistance

differs

remarkably
between

those

parts
disassemble
and

inspect

E

o

Fig
BE
37

Inspection
of
alternator

Rotor

inspection

I

Conduction

test
of
field
coil

Apply
the
tester
between

the

slip
rings
of
rotor
as

shown
in

Figure
EE
38
If

there
is
no

conduction
the

disconnection
of
field
coil

may
exist

When
the
resistance

is

approximately
4
4
n

at
normal

ambient

temperature

the
condition
is

satisfactory

Fig
EE
3B

Conduction
test

of
field
coil
2

Ground
test
of
field
coil

Check
the

conduction
between

slip
ring
and
rotor

core

If
the
conduction
exists

replace
rotor

assembly
because

field
coil

or

slip

ring
must
be

grounded

EE042

Fig
EE
39

GTound
test

of
field
coil

Inspection
of

stator

1

Conduction

test

The

stator
is

normal
when

there
is

conduction
between

the
individual

stator
coil

terminals

When
there
is
no

conduction
between
the

individual
terminals

the
cable
is

broken

Replace
stator
as
an

assembly

EE043

Fig
EE
40

Testing
stator

for
cmlduction

2
Ground

test

If
each

lead
wire

of
stator
coil

including
neutral
wire

is

not
conductive
with
stator
core
the

condition
is

satisfactory
If

there
is

conduction

the
stator
coil
is

grounded
Replace

EE
19

ENGINE

Stator

core

EE044

Fig
EE
41

Testing
stator

for
ground

Inspection
of
diode

Perform
a
conduction
test
on
diodes
in

both
directions

using
an

ohmmeter
A

total
of
six
diodes
are

used
three

are
mounted
on
the

positive
EB

plate
and
other
three
are

on
the

negative
3
plate
The
conduction

test
should
be

performed
on
each

diode
between

the
terminal
and

plate

The
diode
installed
on
the

G
l
plate
is
a

positive
diode

which
allows
current

flowing
from
the
terminal
to

G
l

plate
only
In
other
words
current
does

not
flow
from
the

G
l
plate
to
the
terminal

EE046

Fig
EE
42

Inspecting
positive
diode

The

diode
installed
on
the

8
plate
is
a

negative
diode

which
allows
current

flowing
from
the

8
plate
to
the

terminal

only
In

other
words
current
does
not
flow
from

the

terminal

t08
plate

EE
20
8
Plate

EE047

Fig
EE
43

Inspecting
negative
diode

If
current

flows
in
both

positive
and

negative
diree

tions
the

diode
is
short
circuited
If

current
does

not
flow

in

any
direction
the
diode
is

open
These
diodes
are

unserviceable
If
there
is
a

defective
diode

replace
all

diodes
six

diodes
as
an

assembly
See
the

Figure
EE44

I
Test

probe
of
a
circuit
tester

I
8
E8

I
terminal

E8
plate

I
@
plate
terminal

I
terminal

8
plate

18
plate
te
rminal

18
plate
@

plate

18
plate

8
plate
Conduction

x

x

x

Fig
EE
44

lnspection
of
diodes

Inspection
of
brush

Check
the
movement

of
brush
and
if
the
movement
is

unsmooth
check
brush

holder
and
deJn
it
If
th
bmsh
is

worn
and
the

length
is

7
mm
0

2756
in
or
less

replace

the
brush
with
a
new

one
Check
the

brush

pig
tail
and
if

it
is
about
to
break

replace