1968 DATSUN 510 gas type

CHAPTER
THREE

TROUBLESHOOTING

TroubleshootIng
the
Datsun
can
be

relatlvely

simple
1f
done

lOgically
The
first

step
must

always
be
to
define

symptoms
as

closely
as

pos

Sible

Subsequent
steps
mvolve

testIng
and
an

alyzmg
areas
which
could
cause
the

symptoms

Procedures
m
thiS

chapter
analyze
typical
symp

toms
and

give
lOgical
methods
of
isolation

These
are
not
the

only
methods
There

may
be

several

approaches
to

solvmg
a

problem
but
all

must
have
one

thmg
m
common
a

lOgical

systematic
approach

TROUBLESHOOTING
EQUIPMENT

The

followmg
eqUipment
is

necessary
to

prop

erly
troubleshoot
an

engme

1
Voltmeter
Ammeter
and
Ohmmeter

2

Hydrometer

3

Compression
Tester

4
Vacuum

Gauge

5
Fuel
Pressure

Gauge

6

Dwell
Meter

7
Tachometer

8

StroboscopiC
Trming
Light

9
Exhaust
Gas

Analyzer

Items
1

through
8
are
essentlal
Item
9

is

necessary
for
exhaust
elDlSSion
control

comph

ance
The

followmg
is
a
bnef

description
of
the

functlon
of
each
mstrument
Voltmeter
Ammeter
and
Ohmmeter

For

testIng
the

ignitlon
and
electncal

systems

a

good
voltmeter
is

reqUIred
For
automotIve

use
an
mstrument

covenng
0
20
volts
is
salls

factory
It
should
have
an

accuracy
of
about

Ih

volt
which
excludes
the
common
auto

moUve

type
found
in
instrument

panels

An
ohmmeter
measures
electncal
reSiStance

and

is

reqUired
to
check
electncal

contInUity

open
and

short
circwts
and
for

testing
fuses

and

hghts

The
ammeter
measures
electncal
current
One

for
automotIve
use
should
cover
0
10
and
0
100

amperes
An
ammeter
is
useful
for

checkmg
bat

tery
chargmg
and

startIng
current
The
starter

and

generator
procedures
m
tlus
manual

use
an

ammeter
to
check
for
shorted

wmdmgs
Several

inexpensive
VOM
s
volt
ohmmeters
combme

all
mstruments
and
fit

easily
mto

any
tool
box

The
ammeter

ranges
are
often
too
small
for

auto

motIve
work

thougll

Hydrometer

A

hydrometer
is

necessary
to
check

battery

condition
and

charge
It
measures

specific
grav

ity
of
the

electrolyte
in
each
cell

Compression
Tester

The

compressiOn
tester
measures

compression

10
CHAPTER
THREE

pressure
bUllt

up
In
each

cylInder
The

readIngs

when

properly
Interpreted
IndIcate

general
cyl

Inder
and
valve
condltlOn

Vacuum

Gauge

The
vacuum

gauge
IS

easy
to
use
but
dIfficult

for
an

Inexpenenced
mechanIC
to

Interpret
The

results
when
conSIdered
WIth
other

findIngs
can

prOVIde
valuable
clues
to

pOSSIble
trouble

Connect
the
vacuum

gauge
WIth

a
T
connec

tIon
In
the
hose
from
the
carburetor
to
the

vacuum
advance
on
the
dIstnbutor
Start
the

engme
and
let
It
warm

up
thoroughly
Vacuum

readIng
should
be

steady
at
18
22
Inches

NOTE
Subtract
1
Inch

from

reading

for

every
1000

feet
of
altitude

Figure
1
shows
numerous

tYPical
readIngs

WIth

InterpretatIons
Results
are
not
conclusive

WIthout

companng
to
other
tests
such
as
com

preSSIOn
readIngs

Fuel
Pressure

Gauge

ThIS
Instrument

IS
VItal
for

evaluatIng
fuel

pump
performance
Often

a
vacuum

gauge
and

fuel

pressure
gauge
are
combIned

Dwell
Meter

A
dwell
meter
measures
the
dIstance
In
de

grees
of
cam
rotatIon
that
the
breaker

pOInts

remaIn
closed
while
the

engme
IS

runnIng
SInce

thIS

angle
IS
determmed

by
breaker

pOInt
gap

the
dwell

angle
IS
an
accurate
IndIcatIon
of

pOInt

gap
Many
tachometers
Intended
for

tunIng
and

testIng
Incorporate
a
dwell
meter
as
well
Follow

the
manufacturer
s
InstructIon
to
measure
dwell

on
the
Datsun

Tachometer

A
tachometer
IS
essential
for

tunIng
Datsuns

WIth
exhaust
emission
control
deVices

IgmtIOn

turung
and
carburetor

adjustments
must
be

per

formed
at
the

specified
Idle

speed
The
best
In

strument
for
thIS

purpose
IS
one
WIth

a

range
of

0
1
000
or
0
2
000

rpm
Extended

range
0

6
000
or
8
000
Instruments
lack

accuracy
at

lower

speeds
The
InStrument
should
be

capable

of

detecting
changes
of
25

rpm
Stroboscopic
Timing
Light

ThIS
Instrument

pernuts
accurate

IgnitIon

tImIng
By
f1ashmg
a

bght
at
the

preCISe
Instant

cylInder
No
1
fires
the

posItIon
of
the
crank

shaft

pulley
at
that
Instant

can
be
seen
Marks

on
the

pulley
bne

up
With

a
reference

pOInter
on

the
block

dunng
the

tIming
procedure
SUltable

bghts
are
neon
bulb

types
and
xenon
strobe

hghts
Neon

tunmg
bghts
are
ddticult
to
see
and

must
be
used
in

dImly
bt
areas
Xenon
strobe

bghts
can
be
used
In

bnght
sunbght
Use
the

bght
accordIng
to
the
manufacturer
s
InStruC

tIons

Exhaust

Analyzer

Of
all
Instruments
descnbed
here
this

IS
the

least

bkely
to
be
owned

by
a
home
mechanic

One
Instrument

samples
the
exhaust

gases
from

the

taIlpIpe
and
measures
the
thermal
conduc

tIVIty
of
the
exhaust

gas
SInce
different

gases

conduct
heat
at

varYIng
rates
thermal
conduc

tIVIty
of
the
exhaust
IS

a

good
IndIcatIon
of

gases

present
This
Instrument
IS
VItal
for

accurately

checkIng
the
effectIveness
of
exhaust
emIssion

control

adjustments
but
IS
too

expenSIve
for
an

amateur
mechanIC
to
conSIder

buying

STARTER

Starter

system
troubles
are

relatIvely
easy
to

ISolate
The

followmg
are
common

symptoms

and
cures

1

Engme
cranks

very
slowly
or
not
at
all

Turn
on
the

headhghts
If
the

bghts
are

very
dun

most

likely
the

battery
or
the

connecting
WireS

are
at
fault

Check
the

battery
using
the

pro

cedures
descnbed

in
the
Tune

up
chapter
Check

wmmgfur
e
s
wom
andd
connectIom

H
the

battery
and

connectIng
WIres
check

good
turn
the

headlIghts
on
and

try
to
crank
the

engIne
H
the

lIghts
dIDl

drastIcally
the
starter
is

probably
shorted
to

ground
Remove
the
starter

and
test
it

usmg
the

procedures
gIven
in

Chapter

NIne
If
the

lights
remain

bnght
or
dun

slIghtly

when

crankIng
the

engme
the
trouble

may
be
in

the
starter
solenOId
or

wmng
To
ISolate
the

trouble
short
the
two

large
solenoid
ternunals

together
not
to

ground
if
the
starter
cranks

normally
check
the
solenoid
and

wmng
up
to
the

ENGINE
AND
IGNITION
TUNE
UP
21

many
types
of
test

eqUipment
and

may
be
used

as
a

gUide
If
the
manufacturer

s

mstructioQs
are

not
aVailable
Connections
shown
in

Figure
1

are
as
follows

1
Voltmeter

a
PosItive
lead
to
resistor
side
of
COli

b

Negative
1
ead
to

ground

2

Tlmmg
Light

a
PosItive
lead
to

posItive
battery
termmal

b

Tngger
lead
to
number
1

spark
plug

c

Negative
lead
to

ground

3
Tachometer

a
PosItive

lead
to
dlstnbutor
Side
of
coil

b

Negative
lead
to

ground

4
Dwell
Meter

a

PosItive
lead
to
dlstnbutor
Side
of
COlI

b

Negative
lead
to

ground

BAlTERY
INSPECTION
AND
SERVICE

1
Check
the
level
of
the

electrolyte
m

battery

cells
If

necessary
replemsh
with
distilled
water

Do
not
overfill

2

Measure
the

speCific
gravity
of
the

battery

electrolyte
Refer
to
the

followmg
table
2
Use
the

proper
size
socket
and
wrench
to

remove

spark
plugs
from
the

cyhnder
head

Make
certam
that
the

gaskets
are
removed
from

the

spark
plug
holes

3

Wipe
off
the
msulator
With
a
clean

rag
to

remove

grease
and
dirt

4

Carefully

mspect
the
msulator
and

body
of

each

plug
for

signs
of

cracks
or

chips

Replace

If

faulty

5

Inspect
spark
plug
threads
and
electrodes
for

damage
or
excessive
wear

Replace
as

requrred

Figure
2
shows
the

cond1t
J
on
of

normal
and
de

fectIVe

spark
plugs
along
with

an

explanation

of
the

causes
of

the
abnormal
conditions

6
If
the

spark
plugs
are
still
serviceable
clean

them

thoroughly
With
a

stiff
brush
or

preferably

With
a
sand

blasting
type
of
cleaner

7
File
the

center
electrode

so
that

It
has

a
fiat

surface

8
File
the
surfaces
of
the
outer
electrode

so
that

all
surfaces

are
fiat
and
smooth

9

Usmg
a
feeler

gauge
adjust
clearance
be

tween
the
electrodes
to
0
031
to
0
035
m
0
8

to
0
9mm
as
shown
m

Figure
3

Full

Charge
Value

CD
68

degrees
F

PermiSSIble
Value
20

degrees
C
3

Frigid
chmates

Tropical
chmates

Other
climates
Over
1
22

Over
118

Over
1
20
128

123

126

3
Clean

top
of

battery
and
termmals
With
a

solutIOn
of

bakmg
soda
and
water
Rmse
off
and

dry
thoroughly
Top
of

battery
must
be
clean
to

prevent
current

leakage
between
termmal
and

from

pOSitive
termmal
to
hold
down

clamp
Pro

longed
accumulatIOn
of
aCid
and
dirt
on

top
of

battery
may
cause

blIstenng
of
the
matenal
cov

enng
on
the
connector

straps
and
detenoration

of
the

straps
themselves

4

Tighten
the
cable

connectors
to
the
termmal

securely

5
Coat
the
termmals

lIghtly
With

petrolatum
to

protect
them
from
corrosion

SPARK
PLUGS
INSPECTION

AND
SERVICE

1
Remove

spark
plug
WIres
Mark
them
to
fi

sure
correct

replacement
J

J

I

I

j

j

10
Remstall

spark
plugs
Make
certam
to
use

a
new

gasket
for
each

plug
Use
a

torque
wrench

to

tighten
spark
plugs
from
11
0
to
150
ft
lb

1
5
to
2
0

kg
m

11
Remstall
WIres

DISTRIBUTOR
INSPECTION

AND
SERVICE

Dependmg
on
the
model

year
velucles
have

a

smgle
pomt
or
a
dual

pomt
dlstnbutor

system

30
CHAPTER
FIVE

should
be
1
54
m
39mm
If
the

spnng
tension

is

accurate
the
rehef

valve
should

open
at
54
0

to
59
7
lb

1m
3

8
to
4
2

kg
cm

6
Reassemble
the
oil

pump
Make
certain
all

gaskets
are
mounted
flat

to
avoid
leaks

7
Install
the
dnve

spindle
and
the
oil

pump
to

the
front
cover

8
Install
the
distnbutor
in
the
same
relative

locallon
from
which
it
was
removed
If
the
num

ber
1

cyhnder
was
at

top
dead
center
on
the

compression
stroke
the

punch
mark
on
the
dnve

spindle
should
face
toward
the
front
of
the

engine

9
Install
the
front

splash
shield
and
the
front

stablhzer

10

Insert
the
drain

plug
in
the

pan
and
refill

the

engme

11
Oil

pressure
at
idle
should
be
142
to
17
1

lb

lin
1
0
to
1
2

kg
cm

12

Tlghtenmg
torque
values
for
the
oil

pump

mounting
bolts
is
10
8
to
152ft
lb
1
5
to
2
1

kg
m
and
21
69
to
25
31
ft
lb
3
0
to

25

kg
m

for
the
release

valve

cap
nut

Oil

Filter

The
oil
filter
is
mounted
on
the

nght
hand
side

of
the

cyhnder
block
It

IS
a

cartndge
type
with
built
m

gasket
and
threads
onto
the

mounting

spindle
The
filter
should
be

replaced
every

6
000
miles
as
follows

1
Dram
the

engme
oil
Walt
10
15
minutes

before

removmg
oil
filter

to
allow
It
to
dram

2

By
hand

or
with
the
aid
of

an
oil
filter

wrench

unscrew
the
filter
from
the

spmdle
as

shown

m

Figure
S

3

Cleanmg
of
the

oil
filter

IS
not
recommended

Rather

replace
It
as

reqUIred

4
Thread
the
new
oil
filter
onto
the

mounting

spindle
by
hand
Do
not

overtighten
or

leakage

nught
occur

36
CHAPTER
SIX

0B

34

35

2224
19

21

p
7

31

13

4

7

O

41

rlj
17

11
lOlL
JET

2
Intake
valve

Insert

3
Exhaust
valve
Insert

4
Intake
valve

guide

5
Exhaust
valve

guide
3
2

7
Od

gallery
taper
plug
I

441
J

8

Cylinder
blind

plug

9

Cylinder
blind

plug

10

Taper
plug
21
Washer
34
Rocker
cover

44

Spnng
washer

11

Cylinder
head
011

jet
22
Front
head
cover
35
Rocker
cover

gasket
45
Water
outlet

12
stud
23
Bolt
36
Od
filler

cap
46
JOint
washer

13
stud
24
Front
cover
head

gasket
37
011

cap
paclung
47
stud

14
stud
28
Hex
bolt
38
Rocker
cover
bolt
48
Hex
nut

15
Stud
29
lock

washer
spring
39

Thennostat
a5sem
bly
49

Spring
washer

17
Cylinder
head

gasket
30

Engine
front

Slinger
40
Thennostat
hOUSing
50
Water

temperature

gauge

18

Cylinder
head
bolt
31

Engine
rear

slinger
41
Thennostat

gasket
51
Water

temperature
ground
nut

19

Cylinder
head
bolt
32

Spnng
washer
42
Hex
bolt
53
Cam
bracket
bolt

20

Cylinder
head
bolt
33
Hex
nut
43

Hex
bolt
54
Cam
bracket
bolt

shoe

type
of
tensIOner
reduces
vibration

and

controls
overall
cham

tenSIOn

MANIFOLDS

The
intake
and
exhaust
manifolds
are
shown

in

Figure
10
The
intake
mamfold
IS

made
out

of
cast
aluminum
and
the

eXhaustof
casn
roir

OIL
PUMP

The
oil

pump
is
mounted
to
the
bottom
left

hand
side

of
the
front

cover
Refer
to
the

pre
@

56

CHAPTER
SIX

NOTE
Lubncate
the

cylinder
walls

with
new

engine
oil

prior
to
insertIOn

of
pistOns
Make

certain
that
the

ring

gaps
are
not
In
line

wIth
one
another

Place

the

gaps
180

degrees
from
each

other

and
not

posltloned
either

front

to
back
or

dIrectly
in
line
with

the

piston
pIns

CAUTION

Use
extreme
care
when

Inserting
pzs

tons
so
as
to
avoId

crankshaft

damage

14
With
the
aid
of

a

nng
compressor
illStaIl

the

pISton
and

connectmg
rod
assembhes
into

the

cyhnder
block

as
shown
in

Figure
60
Make

certain
the

proper
piston
IS
mserted
mto
the

proper
hner
and
the
F
on
each

pISton
faces

forward

@

15
Install

beanngs
mto
the

connectIng
rod

caps

after

lubncatmg
them

hghtly

16

Gently
push
connecting
rods
With

beanngs

installed
down
the

cyhnder
until
contact

IS
made

with
the
crankshaft

17
Set

connectIng
rod

caps
over
crankshaft
and

insert

COnnectIng
rod
bolts
Make
certam
that
the

numbers
on
the
rods

and
the
rod

caps
face
in

the
same
direction

18

Tighten
rod
bolts
to
the

proper
torque
speci

ficatIon

as
shown

m

Figure
61

I
J

@v

N

i

19
Check
the

connecting
rod
end

play
With
a

feeler

gauge
as

previously
described

Cylinder
Head
Installation

1

Spread
a
suitable

gasket
seahng
agent
on
the

top
of
the

cylinder
block
and

position
a
new
head

gasket

2

Spread
seahng
agent
on

top
of
the

gasket

CAUTION

PositIon
the

crankshaft
so
that
no

pzston
IS
at

top
dead
center

Before

installing
head

point
the

keys
on
the

camshaft
and

crankshaft

straight
up

Once

the
head
zs

Installed
do
not

rotate
the

camshaft
and

crankshaft

separately
as

damage
to
the

piston

tops
might
result

3
Place
the

cyhnder
gently
onto
the
head

gask
et

NOTE
Three

dIfferent

types
of
bolts

are
used

to
hold
down
the
head

Make

certain
the

proper
ones
are
used

In

the

proper
places

4
Insert
head
bolts

through
holes
ill
head
and

thread
them
mto
the

cyhnder
block

5

Refemng
to

Figure
62

use
a

torque
wrench

and
Datsun
tool
ST49010000
or

equivalent
to

tIghten
the
head
bolts
to

specIficatIon
Tighten

them

gradually
m
three
or
four

stages
wlnle
fol

lOWIng
the

sequence
diagram
Torque
values
are

hsted

m
the

specIfication
table