1973 DATSUN B110 alternator

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

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
ElECTRICAL
SYSTEM

EE127

Fig
EE
45

Brush
wear
limit

Spring
pressure
test

With
the
brush

projected
approximately
2
mm
0

0787

in
from
the
brush
holder
measure
brush

spring

pressure

using
a

spring
balance
Normally
the
rated

pressure
of
a

new
brush

spring
is

255
to
345

grams
9
0
to
12
2

oz

Moreover
when
the
brush
is

worn

pressure
decreases

approximately
20

grams
per
I

mm
0

0394
in

wear

2

rnm
0
0787
in

r

II

EEQ49

Fig
EE
46

Measuring
spring
pressure

REASSEMBLY

Reassemble
the
alternator
in

reverse

sequence
of

disassembly
noting
the

following
matters

I

When
soldering
each
stator
coil
lead
wire
to

the
diode

assembly
terminal

carry
out
the

operatic
as
fast
as

possible

2

When
install
the
diode
A
terminal
install
the

insulating
bushing
and
insulating
tube

correctly

EE
21
EE050

I

Insulating
bush

2
Rear
cover

3
Diode

assembly
4

Insulating
bush

5

A
terminal
bolt

6

Diode
cover

Fig
EE
47
Sectional
view

of
diode
and
A
terminal

3

Tighten
the

pulley
nut
with

tightening

torque
of

350

to
400

kg
cm
301
to
344

in
Ib
When
the

pulley
is

tightened
make
sure
that

deflection
of
V

groove
is
less

than
0
3

mm
0
0118
in

EE051

Fig
EE
4B

TiJ

htening
pulley
nut

ALTERNATOR

TEST

Before

conducting
an
alternator
test
make
sure
that

the

battery
is

fully
charged

To
conduct
a
test
it
is

necessary
to
use
a

3D
volt

voltmeter
and
suitable
test

probes

Set

up
a
test
circuit
as
shown
in

Figure
EE
49
and
test

the
alternator
in
the
manner
indicated
in
the

flow
chart

below

Disconn
ct
connectors
at
alternator

2
Connect
one
test

probe
from
voltmeter

positive

ENGINE

terminal
to
IN
terminal
or
BAT
terminal
Connect
the

other
test

probe
to

ground
Make
sure
that
voltmeter

registers
battery
voltage

4
Start
the

engine
3
Turn
on

the
headlights
and
switch
to
main
beam

I

o

B

ttefY
E

A

J
0

il

I
5
Increase

engine
speed
gradually
until
it
is

approxi

mately
1

100
rpm
and
take
the
voltmeter

reading

6
If
the
measured
value
is
over
12
5

volts
the

alternator
is
in

good
condition
o

I

eE052
Voltmeter

Fig
EE
49

Testing
altematoT

Notes
8
Do
not
run

engine
at
the

speed
of

more
than

1
100

rpm
while
test
is

being
conducted
on

alternator

b
Do
not

race

engine
7
If
the

measured
value
is
below
12

5
volts
the

alternator
is
in

trouble
Remove
and
check
it

for

condition

SPECIFICATIONS
AND
SERVICE
DATA

Specifications

Make
and

type

Nominal

output

Pole

Revolution

No

load
minimum

revolution

Output
current

Wei
t

Applied
regulator

Service
data

Stator
coil

Resistance

per
phase

Rotor
coil

Resistance

Brush

Brush

length

Wear
limit

Spring
pressure

Slip
ring

Outer
diameter
V
A
HITACHI
LTl35
13B

12
35

rpm
Negative
ground

1
000
to
13

500

rpm

A
V

rpm

kg
1b
less
than
1

000

more
than
28

14
2

500

3
4
7
5

TLl
Z
57

n
0
17

at
200C
680F

n
4
4
at
200e
680
F

mm

in

mm
in

kg
lb
14
5
0

571

7
0
2756

0
25
to
0
35
0

55
to
0
77

mm
in
31
1
220

EE
22

Charge
relay

SPECIFICATIONS
AND
SERVICE

DATA

TROUBLE
DIAGNOSES

AND

CORRECTIONS
ENGINE
ElECTRICAL
SYSTEM

Reduction

limit

Repair
limit

Repair
accuracy
mm

in

mm
in

mm
in

REGULATOR

CONTENTS

DESCRIPTiON

MEASUREMENT
OF
REGULATING

VOLTAGE

ADJUSTMENT

Voltage

regu
lator
EE
23

EE
24

EE
25

EE
25

DESCRIPTION
I
0

0394

0
3
0
0118

0
05
0
0197

EE
26

EE
26

EE
27

1

I
T
r

@
V
The

regulator
basically
consists

of
a

voltage
regulator

and
a

charge
relay
The

voltage
regulator
has
two
sets
of

contact

points
a

lower
set
and

upper
set
to

control

altemator

voltage
An

armature

plate
placed
between
the

two
sets
of
contacts

moves

upward
or

downward
or

vibrates

The
lower
contacts
when

closed

complete
the

field
circuit
direct

to

ground
and
the

upper
contacts

when
closed

complete
the
field
circuit

to

ground
through

a
resistance

field
coil
and

produces
alternator

output

The

charge
relay
is

similar
in
construction

to
the

voltage

regulator

When

the

upper
contacts
are

closed

ignition
warning

lamp
goes
on
I
Point

gap

2

Lower
contact

3
Armature

4
Core

gap

5
Yoke

gap

6

Connecting
spring

7
Yoke

8

Adjusting
screw

9
Locle
nut
10

Adjust
spring

11
Coil

12

3mmCO
1181
n
dia

screw

13
4
mm
0
1575

in
dia

screw

14
Contact
set

15

Upper
contact

Regulator
model

Applied
alternator
a
Construction

of

voltage
regulator

TLlZ
57

LTl35
13B

I
Point

gap
10
Lock
ut

2

Charge
elay
antact
Ii
Adjust

spring

3

Connecting

sprinl
12
Coil

4
Armature
i3
3
mm

0
1181
dia

5
Core

gap
screw

6
Yoke

gap
14
4mm
O
1575
n

dia

7
Yoke
crew

8

Adju
ting
screw
15
Contact
set

9
Voltap
e

ree
ulaloT
contact

b

Cons
rue

ion
of

charg
relay

Fig
EE
5J
Structural
view
Fig
EE
50
View

of

removing
cover

As

for
the
construction
the

voltage
regulator
is

very

similar
to

the

charge
relay
as
shown

in

Figure
EE
51

EE
23

ENGINE

MEASUREMENT
OF

REGULATING

VOLTAGE

The

regulator
voltage
is
measured
with
the
alternator

When

measuring
voltage
with

regulator
mounted
on

vehicle
it
is

necessary
to
rotate

engine
at

high

speed

Connect
DC

voltmeter
15

30V
DC
ammeter

l5
30A
battery
and
resistor
0
25
U
with
cables

as

shown
in

Figure
EE
52

1

Check
to
be

sure
that

all
electrical
loads
such

as

lamps
air

conditioner
radio

etc
are
disconnected

2
Before

starting
engine
be

sure
to
make

short
circuit

with

a
cable
between

fuse
side
terminal
of
resistor

O
25U

and

negative
sIde
terminal
of
ammeter

Failure
to

follow
this

caution
causes

needle
of
ammeter
to

swing

violently
and

rever

ely
resulting
in
a

damaged
anuneter

3

Refer

to
the

following
chart
to
determine
if

regulator

and
relative

parts
are
in

good
condition
REGULATOR

Unh
GENERATOR

q

P

1

CONNECTOR

r
l
ij
WIRE

HARNESS
J

Short
circuit
here

between

fuse
side
terminal

and

H

terminal
of

ammeter
before

starting
the

operation

I

I
I
IG

FUSE

BOX

B

f

EE055

Fig
EE
52

Measuring

regulator
voltage
with

regulator

on
vehicle

I
Start

engine

I
2
Rotate

engine
at
2

500

rpm
for
several

minutes

I

1
minutes

ammeter

I
After

racing
for

reading
below
5A
several

Fully

charged
battery
available

I

Replace
with

fully
charged

battery

2
Check

to
see
if

current
falls
below
5A

Current
falls

below
5A
I
After

racing
for
several

reading
over
5A
minutes
ammetet

I

Fully
charged
battery
not
available

1

Connect
a
0
25
n

resistor
in
series

I
Current
does
not

fall
below
5A

I

Recharge

battery
and
see

if
current
falls
below

5A

I

I
Reduce

engine
speed
to

idling
and

then
raise
it

to
2
500

rpm
while

observing
needle

of
voltmeter

I

I

I

Needle
of
voltmeter
held

within
limits
shown
in

the
below

table

Regulator

functioning

properly

EE

24
Needle
of

voltmeter
out
of
limits
shown
in

the

following
chart

Regulator
out
of

order
Have
it

repaired
at

authorized

shop