1968 DATSUN 510 Service Repair Manual

CHAPTER
EIGHT

COOLING
SYSTEM

The

coolIng
system
IS
of
the
closed

pressure

type
Coolant
flows

through
passages
In
the

cyl

mder
head
and
block
and
is
cooled

by
the

radIator
water

pump
and
thermostat

Figure
1

mdlcates
normal
flow

The
radIator
is

a

corrugated
fin

type
wh1le

the
thermostat

IS
a

pellet
desIgn
The
water

pump

IS

centnfugal
and
has

an
alummum
dlecast

body

CD
Several

changes
have
been
made
in
the
water

pump
assembly
over
the

years
pnmanly
be

cause
of

changmg
ennSSlon
cootrol

require

ments
The
diSCUSSIOn
and

procedures
that
fol

low
cover
1970
and
1971

models
However

complete
IllustratIve
material

IS

given
for
all

model

years
so
that

dIfferences
can

readIly
be

identIfied
In
the
models
With
aIr

conditionmg

COOLING
SYSTEM
8S

and

In
those
with
exhaust
and

evaporatIve
emIS

sion
control
devIces
a
fan
clutch
IS
combIned

WIth
the
thermostat
to
detect

temperature
m
the

engme
compartlnent
When
the

temperature

nses
the
thermostat
detects
the

change
an
the

fan
clutch

engages
thereby
helpmg
to
cool
the

engme

WATER
PUMP

Figure
2

page
86
IS
an

exploded
drawmg
of

the
water

pump
and
fan

assembly
for
1970
to

1971
The

top
half
of
the
IllustratIon

applIes
to

those
models
WIth
exhaust
and

evaporatIve

emiSSIOn
control

systems
The
bottom
half
covers

models
WIth
a
crankcase

emiSSIon
control
deVIce

only

Figure
3

page
87

IS
an

exploded
drawmg
of

the
water

pump
and
fan

assembly
for
1968

models
Without
exhaust

or

evaporatIve
controls

Figure
4

page
88
shows
the
1968
model
With

emISSIon
control
deVIce
As

can
be
seen
from
the

illustratIons
most
dIfferences
eXISt
withIn
the

fan
clutch

assembly

Water

Pump
Removal

1
Remove

upper
and

lower
radIator
hoses
from

the
thermostat

housmg
and

cylmder
block
re

spectIvely
Dram
coolant
from
rad1ator
and

cylInder
block

2
Loosen
the
alternator

mountlng
bolt
and
the

adjustIng
bolt
on
the
alternator

mountIng

bracket

3
Move
the
alternator
toward
the

cylinder

block
untIl
slack
IS
eVIdent
10

the
fan
belt
Re

move
fa
belt
fro
alternator
water

pump
and

crankshaft

pulley

4
It
IS
difficult
to
remove
the
water

pump
from

the
front

housmg
With
the
radiator
and

top

shroud
10

place
so
remove
them

5
Remove
the
bolts

holdmg
the
fan

assembly

to
the
water

pump
and
remove
the
fan

assembly

6
Remove
the
bolts

holdmg
the
water

pump
to

the
front

housmg
as
shown
In

Figure
S

Water

Pump
Disassembly
Repair
and

Assembly

Disassembly
or

attempted
repaIr
of
the
water

pump
assembly
IS
not
recommended
If
the

pump
assembly
IS
corroded
the

vanes
are
dam
aged
or
the

bearmgs
are

nOISY

replace
the

entIre
umt

1

Inspect
the
water

pump
assembly
and

replace

If

reqUIred

2

If
the
water

pump
assembly
IS
stIll
serVIce

able
clean
It

thoroughly
before
mstallatIon

3
Assemble
the
water

pump
assembly
m
the

front
cover
10
the
reverse
order
for

disassembly

Do
not
reuse
old

gaskets

4

Replace
the
fan

assembly
on
the

water

pump

and
mstall
the
radiator
and

top
shroud

5

Inspect
the

fan
belt

carefully
for

SIgnS
of

wear

or
cracks
DIscard

It
If
10
doubt

6
Install
the
fan
belt
around
the
crankshaft

pulley
water

pump
pulley
and
the
alternator

pulley

7

Adjust
the
alternator
on
Its
bracket

so
there

IS
no
more
than
0
5
10

deflection
of
the
fan

belt
when

pushed
10

by
thumb

pressure

8

TIghten
alternator
bracket

adjustIng
bolt
and

alternator

mountmg
bolt

securely

9
Install
the

upper
and
lower
rad1ator
hoses

and

tIghten
securely

10
Refill
the
radIator
and

coolmg
system
With

approved
coolant

or
water

NOTE
Because

of
the

many
aluml

num

parts
In
the

engine
a

hIgh
qualIty

antI

freeze

compound
should
be
used

In
the

cooling
system

11
Start
the

engme
and
run
untIl

operatIng

temperature
IS
reached
or
untIl

you
re
sure
the

thermostat
has

opened
and
coolant
IS

CIrCulatIng

throughout
the
entIre

coolIng
system
Top
up

radIator
as

reqUIred

10

f
e

2
Weter
pump
gasket

3
Water
pump
tlXlng
bolt

4
Lock
washer

5
Water
pump
tlXlng
bolt

6
Hex
bolt

7
Hex
bolt

8
Lock
washer

9
Fan
pulley

10
Fan
clutch
assembly

11
Cooling
tan

12
Fan
lock
washer

13
Hex
bolt

14
Fan
belt

15
Dealing
assembly

16
Seal
assembly

17
Seatassembly

18
Lock
wire

19
Vane
assembly

20
Hub
pulley

24
Water
pump
seal
kit
Illl

t
l

10
9
8
n
o
o

19
1
Water
pump
assembly
11
lock
washer

2
Water
pump
body
12
Hex
bolt

3
Water
pump
ane
13
Hex
bolt
With
lock
washer

4
Water
pump
seal
14
loc
l
washer

17
6
5
Water
pump
beanng
15
Fan
and
water
pump
pulley

6
Water
pump
bee
ring
lock
16
Cooling
tan

7
Water
pump
hub
17
Fan
and
water
pump
lock

8
Water
pump
seat
washer

9
Water
pump
gasket
18
Hex
bolt

10
Hex
bolt
19
Fen
belt
I
I

CllAyrElt
EiGll
f

CD
6
1

al

co
t
Sl

1

0

gi

s
co
Oc
3

o
P
c
0
0

tl6

e
cOQ

i
i

fNt
l
tDr

COOLING
SYSTEM
89

FAN
CLUTCH

Fan
Clutch

Operation
and

Inspection

Figure
6
shows
a

typICal
fan
clutch
dISas

sembled
Check
the
umt
whenever
the
water

pump
IS
removed
or
whenever
troubles
are

suspected
m
the

assembly
OperatIon
of
the
fan

clutch
should

be
observed
when
the
vehIcle
is

at

nmning

temperature

Operation
plate
Dust
cover
Drum

o9
Q

SpIder
assembly
LIning

CD

1
Warm

up
the

engme

2
MaIntam

engIne
speed
at
2
500

rpm

3

Usmg
a
thermometer
measure
the

temper

ature
close
to
the
fan
clutch

assembly
on
the

fan

4
The
clutch
should

engage
when
the

temp

erature
reaches
17

degrees
F
65

degrees
C

Conversely
the
clutch
should

deenergIze
when

the

temperature
drops
to
97

degrees
F
54
de

grees
C

5
Take
the
measurements
at
least
twice
SInce

the
thermostat
has
somewhat
of
a
tlme

lag

6
If
the
fan
clutch
falls
to

operate
properly
It

should
be
dIsassembled
and
servIced

Fan
Clutch

Disassembly

1
Follow
the
mstructIons
as

prevIOusly
gIven
to

remove
the
fan
and
clutch

assembly
from
the

water

pump

2
Refer
to
the

appropnate
exploded
illustratIon

for

your
model
and

to

Figure
7
which
shows
a

typiCal
fan
clutch

assembly

3
DIsassemble
unit
and

mspect
all

parts
for

signs
of
wear
or

breakage

4
To
check
the

operatIon
of
the
fan
clutch

thermostat

submerge
the

operatIon

plate
With

the
thermostat
In
hot
water
of
126

degrees
F

70

degrees
C
for
two
to
three
mmutes

Replace

if

It
faIls
to

operate

5
Assemble
the

fan
clutch
m
the
reverse
order

o

dIsassembly
THERMOSTAT

The

system
thermostat
IS
located
inside
the

water
outlet
elbow
on
the

upper
left
hand

por

bon
of
the

cylInder
head
The

temperature
sens

Ing
deVice

IS
threaded
Into
the
base
of
the
therm

ostat

housmg
and
IS
connected

electrlcally
to

the

temperature
gauge
WIthIn
the
vehIcle
dash

board

The

wax

pellet
m
the
thermostat

expands

when
heated
and
contracts
when
cold
The

pellet

IS
connected

through
a

pIston
to

a
valve

Expan

sion

pressure
IS
exerted

agalUst
a
rubber
dIa

phragm
which
forces
the
valve
to

open
and

per

rrut
coolant
to
flow

through
the
entIre

system

As
the

pellet
cools
contractIOn
allows

a

spnng

to
close
the
valve

Thermostat
Removal

1

Open
the
draIn
cock
on
the
bottom
of
the

radiator
and
dram
out

enough
coolant
so
that

the
level
In
the
radIator
IS
below
the
bottom
of

the

upper
radIator
hose

2
DIsconnect
the

upper
radIator
hose
from
the

water
outlet
elbow

3
Remove
the
two
nuts

holdIng
the
water
outlet

elbow
to
the
thermostat

housmg

4
Remove
the

gasket
and
thermostat
from
the

housmg
as
shown
m

FIgure
7

Thermostat

Inspection
and

Replacement

Submerge
the
thermostat
In
a

pan
of
water

Heat
the
water
and
momtor
the

temperature

2
The
thermostat
should
start
to

open
at

1796
1
27

degrees
F
82
1
1
5

degrees
C
Max

Imum

opemng
should
occur
at
203

degrees
F
95

90

CHAPTER

EIGHT

degrees
C
The
maXImum
WIdth
of
the
thermo

stat

openIng
should
be
0315
In
8mm

3
If
the
thermostat
IS
defectIve
or
If

you
have

an
doubts
about
It
mstall
a
new

one

4
When

Installmg
the
thermostat
m
the
hous

Ing
be
certaIn
to

place
the

spnng
end
down

Coat
both
SIdes
of
the

gasket
WIth
sealer
to

pre

vent
leaks
and

tIghten
the

mountlng
nuts

securely

RADIATOR

The
radIator
IS
of
conventional

desIgn
A

draIn
cock
IS

proVIded
at
the
bottom
back
to

perrmt
drainIng
The

system
IS

pressurized
and

the
rehef
valve

incorporated
In
the
filler

cap

mamtains
the

pressure
at

approximately
12
8

Ib
in
0
9

kg
cm
Coolant

capacity
is
1
691

gallons
6

4
lIters

Figure
8
shows
radIator
com
ponents
Note
that
vehicles

equIpped
WIth
auto

matIc
transmISSIon
have

provlSlons
for
connect

Ing
the
011
cooler
lInes
to
the
bottom
of
the

radiator

Radiator

Removal
Inspection

and

Replacement

1
Remove
the

upper
and
lower
radIator
hoses

to
draIn

coolant

2
Remove
four

machme
screws

securmg
radIa

tor
shroud

3
Remove
four

hex
bolts

secunng
rad1ator
to

mountlng
bracket

4
Remove
shroud
and

radIator
from
vehIcle

5

Inspect
radIator
for

SignS
of
leaks

RepaIr
or

replace
as

required

6
InstallatIon

IS
the

OppOSIte
of
removal

CD
14
1
Radiator

assembly
10
Plain
washer

2
Radiator

assembly
11
Plain
washer

automal1c
12
Hose

clamp

3
RadIator

cap
assembly
13
Hose

clamp

4
Drain
cock
handle
14
Radiator

shroud

5
Drain
cock

packing
15
Machine
screw

6

Upper
hose
16
Plain
washer

7
Lower
hose
17

Spring
washer

8
Hex
bolt
18
Hex
nut

9
Hex
nut
19
011
cooler
hoses

Automatic

only

2

i

7

1213

CHAPTER

NINE

ENGINE
ELECTRICAL
SYSTEM

The
electrIcal

system
has

undergone
slIght

yearly
changes
the
most

SignIficant
being
ill
the

distrIbutor
Some
models
have
a

smgle
contact

pomt
whIle
others
have

a
dual

pomt
system
De

talls

are
covered

m
the
dIstrIbutor
sectlon
The

electrIcal

system
IS
a
12
volt

negatIve
type

OPERATION

Figure
1
shows
the

starter
motor
When
the

Ignltlon
sWItch

IS
turned

to
the

start

pOSItIon

current
flows

through
the

senes
and
shunt
colis

of
the

magnetIc
SWitch
and

magnetizes
It
The

plunger
IS

pulled
mto
the

sWItch

operatlng
the

shIft
lever
to

engage
the
dnve

pmlon
with

the

flywheel
rmg
gear
and
to
close
the

magnetIc

SWitch

CD
Figure
2
shows
the
starter
motor
CIrcUIt
Clos

ing
of
the

statlonary
and
movable
contacts
cause

the
motor
to
crank
the

engme
and
cut
out
the

series
coIl
of
the

magnetic
switch
The

magnetic

pull
of
the
shunt
coll

IS
suffiCIent
to
hold
the

pmIOn
m
mesh
With
the

flywheel
nng
gear
after

meshing
has
occurred
After
the

engme
starts

and
the

Ignition
key
IS
released
to
the
on

POSI

1

CD

12
11
10

1

Stationary
contact
8
ShIlt
le
er

2
Sene
coli
9
Orne

pinion

3

IgmtlOn
SWitch
10

Ring

gear

4
Solenoid
11
Plmon
slee
e

spllng

5

Shunt
COil
12
Armature

6

Plunger
13
Movable
contact

7
Return

spllng
14

Battery