1977 DATSUN PICK-UP Service Manual

No
load
test

Connect

starting
motor
in

series

with

specified
12
volts

battery
and

an
ammeter

capable
of

indicating

1

000

amperes

Starter
motor

Diagnoses
of
test

1
Low

speed
with

no
load
and

high

current
draw

may
result
from
the

following

1

Tight
dirty
or
worn

bearings

2

Bent
armature
shaft
or
loosened

field

probe

3
Shorted
armature

Check
armature
further

4

A

grounded
armature
or
field

a
Remove

input
tenninal

b

Raise
two

negative
side
brushes

from
commutator

c

Using
a
circuit
tester

place
one

probe
onto

input
tenninal
and
the

other
onto

yoke

d
I

f
tester
indicates

continuity

raise
the

other
two
brushes
and
check

field
and
armature

separately
to

determine
whether
field
or
armature
is

grounded

2
F

allure
to

operate
with

high

current
draw

may
be

caused

by
the
Engine
Electrical

System

Specified
current

draw
and

revolu

tion
in

these
test
are

shown
in

Specifications

Switch

6
Battery

Et

Voltmeter
Ammeter

Ee026

Fig
EE
20
No
load

l
ting

following

I
A

grounded
or

open
field
coil

Inspect
the
connection
and
trace

circuit
with

a
circuit
tester

2
Armature
coil
does
not

operate

Inspect
commutator
for
excessive

burning
In
this
case
arc

may
occur
on

damaged
commutator
when
motor
is

operated
with
no
load

3
Burned
out
commutator
bar

Weak
brush

spring
tension
broken

brush

spring
rubber
bush
thrust
out

of
mica
in

commu
tat
or
or
a
loose

contact
between
biush
and
com

mutator
would

cause
commutator
bar

to
burn

3
Low

current
draw
and
low

no
load

speed
would

cause

high

internal
resistance

due
to
loose
con

nections

damaged
leads

dirty
corn

mutator
and
causes
listed
on
item

2

3

EE10
MAGNETIC
SWITCH

ASSEMBLY
TEST

Switch

o

Fv
IB
I

I

D

Battery
Starter
motor

EE351

FiN
EE

21
Circuit

ofmagndic
awitch

assembly
ted

If
the

starting
motor
check
is

OK
check

magnetic
switch
as

sembly
Connect
cables

between

negative
battery
tenninal

and
start

ing
motor
M
terminal

positive

battery
terminal
and

starting
motor

S
terminal

connecting
a
switch
in

series
as

shown
in

Figure
EE

21

With
the
switch
on

push

pinion

back
to

remove
all
slack
and

measure

the
clearance
l
between

pinion

front

edge
and

pinion
stopper
The

clearance
should
be

held
within
0
3
to

1
5
mm

0
012
to
0

059
in

If
neces

sary
adjust
it

by
changing
or

adding

adjusting

washer
s

Adjusting
washers

are
available
in

to
two

different
sizes

0
5
mm
0

020
in

and
O
S

mm
0
031

in

0
3
to
I
S
rom

0
012
to
0
059
in

l

EE029

Fig
EE
22
MeO

uring
clearance

t

Engine
Electrical

System

SERVICE
DATA
AND
SPECIFICATIONS

Type

System
voltage

No
load

Terminal

voltage

Current

Revolution
v

V

A

rpm

Brush

length
Outer
diameter
of
commutator
mm
in

mm
in

Brush

spring
tension

kg
Ib

Clearance
between

bearing
metal
and

armature
shaft
mm
in

Clearance
L
between

pinion
front

edge
and

pinion
stopper
mm
in

TROUBLE
DIAGNOSES
AND
CORRECTIONS

Condition

Starting
motor
will

not

operate

Noisy
starting
motor

Starting
motor

cranks

slowly
Probable
cause

Discharged
battery

Damaged
solenoid
switch

Loose
connections
of
terminal

Damaged
brushes

Starti

g
motor

inoperative

Loose

securing
bolt

Worn

pinion

gear

Poor

lubrication

Worn
commutator

Worn
brushes

Discharged
battery

Loose
connection
of
terminal

Worn
brushes

Locked
brushes

EE
ll
Manual

transmission
Automatic

transmission

Optional

for

manual

transmission

SII4
ISOB

S114
170B

12

12

Less
than

60

More

than
7

000
More
than
6
000

More
than
39

1
54

More
than
12
0
47

1
4

to
I
S
3
1
to
4
0

Less
than

0
2
O
OOS

0
3
to
1
5
0
012
to
0

059

Corrective
action

Charge
or

replace
battery

Repair
or

replace
solenoid
switch

Clean
and

tighten
terminal

Replace
brushes

Remove

starting
motor
and
make
test

Tighten

Replace

Add
oil

Replace

Replace

Charge

Clean
and
tighten

Replace

Inspect
brush

spring
tension

or

repair
brush

holder

Condition
Engine
Electrical

System

Probable
cause

Starting
motor

cranks

slowly
Dirty
or
worn
commutator

Armature
rubs

field
coil

Damaged
solenoid
switch

Starting
motor

operates
but
does

not
crank

engine
Worn

pinion

Locked

pinion
guide

Worn

ring

gear

Starting
motor
will

not

disengage
even
if

ignition
switch
is

turned
off
Damaged
solenoid
switch

Damaged

gear
teeth

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

operat

ed
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

IF

terminal
alternator
IF
terminal

rotor

field
coil
and
alternator

E

terminal

as
shown
in

Figure
EE

23

by

full
line

arrow
marks
Then
the

rotor

in

the

alternator
is
excited

On
the

other
hand

current
flows

from
the

battery
to

ground

through
the

ignition

switch

warning

lamp
voltage
regula

tor
L

terminal

lamp
side
contact

point
P4

movable

contact

point

P5
and

voltage
regulator
E
termi

nal
as
shown

by
dotted

line
arrow
CHARGING
CIRCUIT

marks
Then

the

warning
lamp
lights

When
the
alternator

begins
to

op

erate
three

phase

alternating
current
is

induced
in

the

stator
armature
coil

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
24

by

the
dotted
line
arrow
marks
Then
the

coil
VCI
is
excited
and
the

movable
contact

point
IPS
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
full

line
arrow
marks

When
the
alternator

speed
is
in

creased
or
the

voltage
starts
to
rise

excessively
the
movable
contact

point

EE
12
Corrective
action

Clean
and

repair

Replace
assembly

Repair
or

replace

Replace

Repair

Replace

Repair
or

replace

Replace
damaged

gear

P2
is

separated
from

the

primary

side
contact
PI

by
the

magnetic

force

of
coil
VC2
Therefore

registor
RI
is

applied
into
the
rotor

circuit

and

output
voltage
is
decreased

AJ

the

output
voltage
is
decreased

the

movable
contact

point
P2
and

primary
side
contact
Pin

comes
into

contact
once

again
and

the
alternator

voltage
increases

Thus
the

rapid

vibration
of
the
movable

contact

point

IPl

maintains
an
alternator

output

voltage
constant

When
the
alternator

speed
is

further

increased
or
the

voltage
starts
to
rise

excessively
the

movable
contact

point

P2
comes

into
contact
with

secondllJ
side
contact

point
P3

Then
the
rotor
current
is

shut
off
and

alternator

output
voltage
is

decreased

immediately
This

action
causes

movable
contact
n
to

separate

from

secondary
contact
P3
Thus

the

rapid
vibration
of

the
movable

contact

point
P2

or

breaking
and

completing
the

rotor
circuit
maintains

an
alternator

output
voltage
constant

Engine
Electrical

System

r
l

I

I

I

i

r
Ye
Ff
p

Stator
ma

ture
coiJ

FF
vw

I

I
RI

L

Rot
r

field
C
oil

e
R

I

I

I
I

I

J

1
J

Alternator

Voltage
regulator
11

t

c

I

Fusible
link

t
8

c

J
5

9

i
c
c

0

Battery

t
u
J

EE029

Fig
EE
23

Charging
circuit

II

p
ns

1

Slator
ar

ature
coil

teJ

U

2iI
I

r
R
l
I

I

A3

R2
0
Fusible
link

Roto
field
coil

e

I
I
t
I

I
PS

M
g

j

t

i

H
U

Battery

Lh

A

l
a
o
J

L

V

It

g
t

f

EE030

Fig
EE

24

Charging
circuit
II

EE

13

Engine
Electrical

System

B

v

W

WR

WL

L2
VOLTAGE
REGULATOR

co

LW

I
P
B

r

FUSIBLE
LINK

m
I
WLI

LW

cJ

I

B

t
EARTH
POINT
m
WR
WR

CHARGE

g
00
WARNING
lAMP

00000

Equipped
with

cooler
I
I
I
I

TjT
m

CLB

W

WB
B
YWR

I
I
I
I

1
W

B

rn

ALTERNATOR
I

l
LW
BW

j
J

M
IG
I

W

BwtIl

IGNITION
SWITCH

COLOR
CODE

B
Black

OW
Black
with

white

stripe

W
White

WB
White
with
black

stripe

WR
White
with
red

stripe

WL
White
with
blue

stripe

LO

Blue
with

black

stripe

LW
Blue
with
white

stripe

Y
Yellow
lOA

C
o
0
0
0

o
0
0
FUSE

BLOCK

M
0
0
0

lOA

Ii

California
models

E
E492

Fig
EE
25
Circuit

diagram
of
charging
lfY
t

m

EE
14

DESCRIPTION

REMOVAL

DISASSEMBLY

INSPECTION
AND
REPAIR

ROTOR
INSPECTION

INSPECTION
OF

STATOR

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
current
Silicon
diodes
act

@God

A
tfff
Engine
Electrical

System

ALTERNATOR

CONTENTS

EE
15

EE
16

EE
16

EE
16

EE
17

EE
17
INSPECTION
OF
DIODE

INSPECTION
OF
BRUSH

SPRING
PRESSURE
TEST

ASSEMBL
Y

ALTERNATOR
TEST

SERVICE
DATA
AND
SPECIFICATIONS
EE
17

EE
1B

EE1B

EE

1B

EE19

EE
19

like
a
one

way
valve
for

electricity
so

that

charging
current

passes
easily
but

reverse
current
is
shut
out

In
this
alternator

pack
type
silicon

di
odes

are
used

Six

diodes
three

negative
and
three

positive
are
installed
in

positive
and

negative
plates
as
an

assembly

These
diodes
are
direct
soldered
at

their

tips
and
constructed
with

posi

3

2

I
4

e

o

e

9
tive
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

The

pulley
mounted
on
the
air

conditioner
models
is

different
from

that
on
the

standard
models
without

air
conditioner

1

Pulley
usem

bly

2
Front
cover

3
Front

bearing

4

Rotor

5

Rear

bearing

6
Stator

7
Brush
assembly

8
Rear
cover

9

Diode
set

plate
assembly

10
Diode
cover

11

Through
botrs

EE
15
EE345

Fig
EE
26

Exploded
view

REMOVAL

1
Disconnect

negative
battery
ter

minaL

2

Disconnect
two
lead
wires

and

connector
from
alternator

3
loosen

adjusting
bolt

4

Remove
alternator
drive
belt

5
Remove

parts
associated
with

alternator
from

engine

6

Remove
alternator
from

vehicle

DISASSEMBLY

1
Remove

pulley
nut
and

pulley

assembly

11

C

@@@
EE033

Fig
EE
27

Removing
pulley
ond

fan

2
Remove
brush
holder

fIxing

screws
and
remove
brush
holder

cover
Pull
brush
holder
fOIWard

and

remove
brushes

together
with
brush

holder

Note
Do
not

disconnect
N
tenninaJ

from
stator

coil
lead
wire

EE346

1
N
terminal

2
Brush

holder

3
Brush
holder

co
r

Fig
EE
28

Remouing
brush
Engine
Electrical

System

3
Remove

through
bolts

Separate

front
cover
with

rotor
from
rear
cover

with
stator

by
lightly

tapping
front

bracket
with
a

wooden
mallet

J

J

4

C

EE035

Fig
EE
29

Separating
front
cover

with

rotor

from
rear

cover

4
Remove
three
set

screws
from

bearing
retainer

and

separate
rotor

from
front
cover

DO
Q
EE036

Fig
EE
3D

Removing
rotor

5

Pull

rear

bearing
out
from
rotor

assembly
with

a

press
or

bearing

puller

L

I
EE037

Fig
EE
3I

Pulling
out

of
roar

bearing

EE
16
6
Remove
diode

cover

fIXing
screw

and

remove
diode

cover
Disconnect

three
stator

coil
lead
wires
from

diode

terminal

with
a

soldering
iron

7
Remove

A
tenninaJ
nut
and
diode

installation

nut
and

remove

diode

assembly

CD

AJ

f
e

ecA

O

1
Diode

assembly

o

2
Diode
cover
o

EE039

Fig
EE
32

Removing
diode

088embly

Note
Use
care

in

assembly
to

on
it
handling
diode

an

undue

st

INSPECTION
AND

REPAIR

Remove

alternator
from
car

and

connect
a
circuit
tester
between
F

tenninal
and
E
terminal

When
the
resistance

is

approxi

mately
5il
the
condition
of

brush
and

fIeld
coil
is

satisfactory
When
no

continuity
exists
in
brush
or
fIeld

coil
or

when
resistance
differs

significantly
between
those

parts
dis

assemble
and

inspect

A

o
E

O

1

ld

Q

EE040

Fig
EE
33

Inspecting
alternator

ROTOR
INSPECTION

1

Continuity
test
of
rotor
coil

Apply
tester
between

slip
rings
of

rotor
as

shown
in

Figure
EE
34
If

there
is
no

continuity
field
coil
is

open

Replace
rotor
assembly

EE041

Fig
EE

34

Continuity
test

of
rotor

coil

2

Ground
test
of
rotor
coil

Check

continuity
between

slip
ring

and
rotor
core
If

continuity
exists

replace
rotor

assembly
because

rotor

coil
or

slip
ring
may
be

grounded

Fig
EE

35

Testing
rotor
coil

for

round

INSPECTION
OF
STATOR

1

Continuity
test

Stator
is
normal
when

there
is

continuity
between
individual
stator

coil
tenninals
When
there
is
no
conti

nuity
between
individual
terminals

cable
is
broken

Replace
with
stator
assembly

EE043

Fig
EE
36

Testing
stator

for

continuity
Engine
Electrical

System

2
Ground

test

If

each
lead
wire
of
stator
coil

including
neutral
wire
is
not
conduc

tive
with
stator
core
condition
is

satisfactory
If
there
is

continuity

stator
coil
is

grounded

EE045
Stator
core

Fig
EE

37
Ee044

Teding
stator

for

P
Ound

Conductive
direction

I

Diode
installed
on
EEl

plate
is

a

positive
diode
which
allows
current

flowing
from
terminal
to

EEl

plate

only
In
other
words
current
does
not

flow
from

EEl
plate
to
terminal

v

1
ptate

2
Terminal
EE046
INSPECTION
OF
DIODE

Perform
a

continuity
test
on

diodes

in

both
directions

using
an

ohmmeter

A

total
of
six

diodes
are
used
three

are
mounted
on
the

positive
EEl
plate

and
other
three

are
on
the

negative
e

plate
The

continuity
test

should
be

performed
on
each
diode
between
the

terminal
and

plate

I

plate

2
ptate

3
Diode

Fig
EE
38
Conductive
direction

of
diode

Diode
installed

on
e

plate
is

a

negative
diode
which
allows
current

flowing
from

e
plate
to
terminal

only
In
other
words
current
does
not

flow
from
terminal
to

e
plate

I

plate

2
Terminal
EE047

Fig
EE
39

Inspecting
positive
diode

Fig
EE
40
Insp
cting
negative
diode

EE
17