1968 DATSUN 510 air condition

CHAPTER
TWO

PERIODIC
MAINTENANCE

To
ensure

good
performance
dependability

and

safety
regular
penodlc
maintenance
is

necessary
TIns

chapter
outlInes
routine

and

penodlc
mamtenance
for
the

average
dnver

Under

heavy
usage
semcmg
mtervals
will
be

shortened

Regular
routme
mamtenance
will

help
aVOId

expensive
repaIrs

ROUTINE
CHECKS

The

followlDg
checks
should
be

performed
at

each
fuel

stop

1
Check

engme
oil
level

Top
up
as

requrred

2
Check
radiator
coolant
level

Top
up
as
re

qwred

3
Check

battery
electrolyte
The

battery
case

IS
marked
With

upper
hrmt
and
lower
lnmt
lInes

Level
should
be
maID
tamed

between
the
IIDes

4
Check
that
the
master

cylInder
brake
flwd

reservOir
level
IS
between
the
max
and
mm

lInes
marked
on
the

plastic
case

S

Check
the

plastic
clutch

cyhnder
reservoir

level
Level
should
be
between
the
max
and

mm
lInes

6
Check
the
windsh1eld
washer
flwd
reservoir

Top
up
as

required
7
Check
tire

pressures
when
the
tIres
are
cold

Front
and
rear
tire

pressures
should
be
24

pounds
under
normal

dnving
conditions
TIre

pressure
should
be
28

pounds
for

h1gh
speed

dnvmg
conditions

8
Check
the

engIne
for

general
conditIon

Check
for

leaky
or
cracked
hoses
and
loose

wmng

9
Check
condition
of
wmdshleld

wiper
blades

PERIODIC
CHECKS

Table

1

prOVIdes
penodIc
checks
and
main

tenance
that
should
be

performed
on
a
set

schedule
Table
2

gIves
recommended
lubncants

and
Table
3

specIfies
the

grades
of
oil
that
should

be
used
Procedures
for

performmg
the
semces

are

presented
ID
vanous

chapters
of
tlus
manual

Table
3
RECOMMENDED
GRADES
OF
OIL

Temperature
Engine
on

MS

Above
32
C
90

F
average
SAE
30
IOW
30

32
to
0
C
90

to
32

F
mlmmum
SAE
20
20W
IOW
30

O
to
12
C
32
tolO

F
mlRlmum
SAE
IOW
IOW
30

Below
12
C
10
F
mlmmum
SAE
lOW
IOW
30

TROUBLESHOOTING
13

trouble

may
also
be
worn

bearings
Remove
the

alternator
and

repair

ENGINE

These

procedures
assume
the
starter
cranks

the

engme
over

normally
If
not
refer
to
Starter

section
m
this

chapter

1

Engme
won
t
start

Could
be

caused

by
the

IgOltlon
or
fuel

problems

First
determine
If

high
voltage
to

spark
plug

occurs
To
do
thiS
dISconnect
one
of
the

spark

plug
wires
Hold
the

exposed
wrre
termlOal
y
to

Y2
lOch
from

ground
any
metal
in

engine
com

partment
With
an
msulated
screwdriver
Crank

the

engme
over
If

sparks
do
not

Jump
to

ground

or
the

sparks
are

very
weak
the
trouble

may
be

10
the

IgnitIOn
system
See

Ignition
System
Trou

bleshootmg
to
further
check
If

sparks
occur

properly
the
trouble

may
be
10
the
fuel

system

See
Fuel

System
Troubleshootmg

2

Engme
misses

steadily

Remove
one

spark
plug
wrre
at
a
tune
and

ground
the
wrre
If

engme
mISs
increases
that

cyhnder
was
work

109
properly
Reconnect
the

wire
and
check
the
others
When
a
wire

IS
dIs

connected
and

engme
miss
remams
the
same

that

cylinder
IS
not

finng

Check

spark
as
descnbed
10

Step
1
If
no

spark

occurs
for
one

cyhnder
only
check
dlStnbutor

cap
wrre
and

spark
plug
If

spark
occurs

prop

erly
check

compressIOn
and
mtake
maOlfold

vacuum
to
ISolate
the
trouble

3

Engme
misses

erratlcally
at
all

speeds

Interrmttent
trouble
can
be
difficult
to
find
It

could
be
ill
the

Ignition
system
exhaust

system

or
fuel

system
Follow

troubleshooting
proce

dures
for
these

systems
carefully
to
isolate
the

trouble

4

Engme
misses

at
Idle

only

Trouble
could
exist

anywhere
ill

IgOltlon
system

Follow

Ignition
TroubleshootlOg
procedure
care

fully
Trouble
could
also
eXist
10
the
carburetor

Idle
crrcult
Check
Idle
mIXture

adjustment
and

check
for
restnctions
m
the
idle
crrcUlt

5

Engme
misses
at

high
speed
only

Problems
could
be
ill
the
fuel
or

IgOltlon
systems
heck
accelerator

pump
operation
fuel

pump

dehvery
fuel
hnes
etc
as
descnbed
under
Fuel

System
Troubleshootillg
Also
check

spark
plugs

and
wrres

6
Low

performance
at
all

speeds
poor

acceleratIOn

Trouble

usually
ill

IgOltlon
or
fuel

system
Check

each
With
the

appropnate
troubleshooting
pro

cedure

7
ExceSSive

fuel
consumptIOn

Could
be
caused

by
a

Wide

variety
of

seemmgly

unrelated
factors
Check
for
clutch

shppage

brake

drag
defective
wheel

beanngs
or

poor

front
end

alignment
Check

IgOltlOn
system
and

fuel

system

8
011

pressure
lamp
does
not

light
when

IgmtlOn

switch

IS
on

Check
the
alternator

warning
lamp
If
it
ISn
t
on

either

go
to

Step
1

Chargmg
System
Trouble

shootlOg
If

only
the
oil

pressure
lamp
IS
off

open

the

englOe
compartment
hd
and
locate
the
oil

pressure
sender
on
the
block
near
the
oil
filter

Make
sure
the
wrre
is
connected
to
the
sender

and

makmg
good
contact
Pull
the
wrre
off
and

ground
it
If
the

lamp
hghts
replace
the
sender

If
the

lamp
does
not

light
replace
the

lamp

9
011

pressure
lamp
lights
or

flickers
when

engme
IS

runmng

Indicates
low

or

complete
loss
of
oil

pressure

Stop
the

englOe
unmedmtely
coast
to
a

stop
With

the
clutch

dISengaged
Tlus

may

simply
be

caused

by
a
low
oil
level
or
an

overheatmg
en

glOe
Check
the
oil
level
and
fan
belt
tensIOn

Check
for
a
shorted
oil

pressure
sender
with
an

ohmmeter
or
a

contlOulty
tester
Remove
and

clean
the
oil

dipstick
and
check
oil
level
and

condition

RepleOlsh
or

replace
the
oil

as
re

qurred
Listen
for
unusual
nOISes

mdlcatmg
dam

aged
beanngs
etc
Do
not
re
start
the

engine

until

you
know

why
the

hght
went
on
and

are

sure
that
the

problem
has
been
corrected

IGNITION
SYSTEM

This

procedure
assumes
the

battery
IS
ill

good

enough
condition
to
crank
the

engme
at
a

normal
rate

TROUBLESHOOTING

15

5

Stumbling
when

acceleratmg
from
Idle

Check

accelerator

pump
diaphragm
and
Idle

speed
adjustment

6

Engine
mISses
at

hIgh

speed
or
lacks

power

This
mdlcates

pOSSible
fuel
starvatIon
Check

fuel

pump
pressure
and

capacIty
Clean
main

Jet

and
float
needle

valve

7
Black
exhaust
smoke

Black
exhaust
smoke
means
a

badly
ovemch

nuxture
Check
Idle

mIXture
and
Idle

speed
ad

Justment
Check
for
excessive
fuel

pump
pres

sure
or
blocked
return
hne
from
carburetor

to

fuel
tank
Check
for

leaky
float
or
worn
needle

valve

8
ExceSSIve

fuel

consumptIOn

ThIS

may
be
another
mdIcatIon
of

an
ovemch

fuel
mixture
Check
that
automatIc
choke

oper

ates

If
so

eqUIpped
or
that
the
manual
choke

contraIlS
not

being
left
out
Check
Idle
mIXture

and
Idle

speed
Check
for
excessIve
fuel

pump

pressure
leaky
float

or
worn
needle

valve
Make

certam
that

jets
are
the

proper
SIZe

Fuel

Pump
Pressure

Testing

1
Install
a
T

fittmg
m
the
fuel
hue

close
to
the

carburetor

2
Connect
a
fuel

pressure

gauge
to
the

fittmg

WIth
a
short
tube

3
Check
fuel

pump
pressure
as
described

in
the

Fuel

System
chapter

EXHAUST
EMISSION
CONTROL

The

followmg
symptoms
as
ume

you
have
ad

justed
the

Ignition
and
carburetor

to

specdicatIon

and
that

you
have
checked

the
results
on
an

accurate
exhaust

gas
anajyzer

1
CO

content
too
low

Make

sure
Idle

speed
IS
not
too
low
Check
Idle

mIXture

adjustment
too
lean
Check
carbu

retor

Jets
and

channels
Clean
and
or

replace
as

necessary
Check

engme
condition
With
a
com

pressIOn
and
vacuum
test

2
CO
content
too

hIgh

Check
Idle
mixture

adjustment
too

nch
Check

for

dIrty
air
cleaner

and
defectIve

automatIc

choke
If
so

equipped
Check
carburetor

Jets
and
channels
Clean
and
or

replace
as

necessary

Check

engme
condItIon
WIth

compression
and

vacuum
test

3

Hydrocarbon
level
too

hIgh

Check
that

Idle

speed
and
mIXture

adjustments

are

to

specIfication
Check

spark
plug
condItIon

and

gap
Check
breaker

pomts
Check

IgnItIon

tnumg
too

early
Check
mtake

mamfold
for

leaks
Check

valve
clearance
too

small
Check

condItIon

of
valves
With

compressIOn
test

MANUAL
CLUTCH

1

SlIppage

ThiS

is
most

noticeable
when

acceleratIng
m
a

hIgh
gear
at

relatIvely
slow

speed
To

check

slip

page
park
the
car
on

a
level
surface

WIth
the

handbrake

set
ShIft
to
2nd

gear
and
release
the

clutch

as
If

drlVing
off
If
the

clutch
is

good
the

engme
will
slow
and
stall
If
the

clutch

shps
con

tInued

engme
speed
will

gIve
It

away

CAUTION

ThIS
IS
a
severe

test

Perform

only

when

slippage
IS

suspected
not

penodlcally

Shppage
results
from
IDSufliclent
clutch

pedal

free

play
all
or

grease
on
the

clutch
disc

worn

pressure
plate
or
weak

sprmgs
Also
check
for

bIndIng
m
the
clutch
cable

and
lever
arm
which

may

prevent
full

engagement

2

Drag
or

failure
to
release

ThIS

problem

usually
causes
dIfficult

shIftIng
and

gear
clash

espeCially
when

downshIftmg
The

causes

may
be
excessive
clutch

pedal
free

play

warped
or
bent

pressure
plate
or
clutch
dISC
ex

cessive
clutch
cable

guide
sag
and
broken
or

loose
clutch

lmings
Check
conditIOn
of

mam

shaft

splines

3
Chatter
or

grabbing

A
number
of

thmgs
can
cause

tIns
Check

cable

gUIde
sag
and

tIghtness
of
transnusslOn
to
frame

and

engme
to
transmlSslon

mountIng
bolts

Check
for

worn
or

mISaligned
pressure
plate
and

misalIgned
release

plate

4

Other
nOIses

NOISe

usually
mdlcates
a

dry
or
defective
release

bearIng
Check
the

beanng
and

replace
If
neces

16

CHAPTER

TIlREE

sary
Also
check
all

parts
for

mlSaltgnment
and

uneven
wear

TRANSMISSION

1

Difficult
to
mesh

gears

Make
certam
the

clutch

pressure
plate
and
re

lease

beanng
are
m

good
condItion
The
trouble

can
be

caused

by
worn

gears
shaft
and
or
bear

mgs
DISassemble
and

repaIr
as

requIred
Also

can
be
caused

by
msufficlent

operatmg
stroke

due

to
worn
or
loose

sltdmg
parts
or
a
defective

synchronIZer
DIsassemble

carefully

InSpect
and

replace
as

requIred

2
Gears

slip
out

of
mesh

Generally
thIS
trouble
occurs
when

the
mterlock

plunger
check
ball
and

or

spnng
IS
weakened

or
worn
The
trouble
can

also
be
caused

by
worn

fork
rod
ball

groove

damaged

bearings
or
dam

aged

gears
DIsassemble

carefully
mspect
and

replace
as

required

3
NOIse

If
nOISes
are
heard

wIth
the

engme
idlmg
and
the

clutch

disengaged
the
nOIse
IS

probably

conung

from
the

transmISSIOn
Several
Items

can
cause

nOISes

either

smgly
or
m
combmatIon

Check
the

qualIty
and

quantity
of
lubrIcant

in
the
trans

mISSIon

Replace
or

replenISh
as

necessary
Worn

bearIngs
wIll

usually
produce
a

lugh
humming
at

hIgh
speed
and

a

cycltc
knockIng
sound
at
low

speed
Worn

or

damaged
splInes
and

bushmgs

will
also
cause

nOIse

BRAKES

1
Brake

pedal

goes
to

floor

There

are
numerous
causes
for
thIS

includIng

excessIvely
worn

Itnmgs
aIr
in
the

hydraultc

sys

tem

leaky
brake
lmes

leaky
wheel

cylmders
or

leaky
or
worn

master

cylmder
Check
for
leaks

and
thIn
brake

linmgs
Bleed
and

adjust
the

brakes
If

thIS
doesn
t
cure
the
trouble

rebwld

wheel

cylmders
a
nd
or
master

cylmder

2

Spongy

pedal

Normally
caused

by
aIr
m
the

system
blee
d
and

adjust
the
brakes

3

Brakes

pull

Check

brake

adjustment
Also
check
for
contam
inated

brake

Itmngs
from
leaks

leaky
wheel

cyltnders
loose

caltpers
frozen

or
seIZed

pIstons

and
restrIcted
brake
lmes

or
hoses
In
addItion

check
front
end

alignment
and

suspensIOn
dam

age
such
as
broken
front

or
rear

sprmgs
shocks

etc
Check
condItIon

of
tIres

4
Brakes

squeal
or
chatter

Check
brake

lmmg
thickness

and
brake
drum

roundness
Ensure

that
the
shoes
have
cham

ferred
ends

and
are
not
loose

Inspect
the
condI

tion
of

the
rotors
on
the
front
wheel
dISC

brakes

to
make

certain

they
are
not
scored

or

damaged

Clean

away
all
dIrt
on
shoes

pads
rotors

or

drums

5

Draggmg
brakes

Check

brake

adjustment
includmg
handbrake

Check
for
broken
or

weak
shoe
return

springs

swollen
rubber

parts
due
to

unproper
brake
flUId

or
other
contammatIon

Clean
or

replace
de

fectIve

parts

6
Hard

pedal

Check
brake

linmgs
for

contammation
Also

check
for

restrIcted
brake
lines

and
hoses

7

High
speed
fade

Check

for
dIstorted
or
out
of
round
drums

and

contamInated
brake

lmmgs
Make

certam
the

recommended
brake
flUId
IS

used
Dram
entIre

system
and
refill
If
In
doubt

8

Pulsatmg
pedal

Check
for
dIStorted
or
out
of
round
drums

or

rotors
Check
for

excessIVe
brake

dISC
run
out

STEERING
AND

SUSPENSION

NOTE
Unusual

steermg
pullmg
or

wandermg
IS

usually
caused

by
bent

or
otherwise

mIsaligned

suspenszon

parts
Because

of
the

speCialized
equIp

ment

reqUired
to
evaluate
and

correct

these

faults
It
IS
recommended

t
tat

servIce
to

the

steermg
and

suspension

system
be

referred
to

your
Datsun

dealer

oca

quallfied
specrallst
m

thiS

field

1
VibratIOn

felt
m

steermg
wheel

VIbratIon
can
be
caused

by
several

thmgs
includ

ing
lll1proper
aIr

pressure
m
tIres

uneven
wear

22
CHAPTER

FOUR

CD

Normal

plug

appearance
noted

by
the
brown
to

graYish
tan

deposits
and

slight
electrode

wear
This

plug
rndlcates
the
correct

plug
heat

range
and

proper
air
fuel
ratio

f

j

l

Carbon

fouling

dlstrngUlshed
by
dry
fluffy
black

carbon

deposits
which

may
be
caused

by
an
over

nch
alr
fuel
mixture
excessIVe

hand

chokrng

clogged
air
filter

or
excessive
Idling

lJ
6

1

4i

Z

011

fouling
rndlcated

by
wet

OIly

depOSits
caused

by
011

pumprng
past
worn

rrngs
or
down
the
rntake

valve

gUides
A
hotter

plug
temporanly
reduces
011

depOSits
but
a

plug
that
IS

too
hot
leads
to

pre

IgmtlOn
and

possible
engrne
damage
Red
brown

yellow
and
white

coatrngs
caused

by

fuel
and
011
additives
These

depOSits
are
not
harm

ful
If

they
remarn

rn
a

powdery
form

C

I

Shrny
yellow
glaze
on
rnsulator

cone
IS
caused

when

the

powdery
depOSits
from
fuel
and
011
additives

melt

Meltrng
occurs
dunng
hard

acceleration
after

prolonged
Idling
This

glaze
conducts

electnclty

and
shorts

out
the

plug

Overheated

plug
rndlcated

by
burned
or
blistered

rnsulator

tip
and

badly
worn
electrodes
This
condl

bon

may
be
caused

by
pre
Igmtlon
cooling
system

defects
lean
air

fuel
ratiOS
low
octane
fuel
or
over

advanced

Igmbon
bmrng

Spark
plug
condition

photos
courtesy
of
At

Spark
Plug
DIvision
General
Motors

Corporation

The

procedures

given
below
would

generally

apply
to
eIther

type
In
the
dual

pomt
system

one
set
of

pomts
IS
known
as
the
advance
set

and
the
other
the
retard
set

Complete
details

are

given
m

Chapter
Nme

Figure
4
IS
a
detaIl

of

the
dual

pomt

system

1
Remove
dIStnutor

cap
Clean

It

carefully
to

remove

grease
or
dIrt

2
Examme
the
mSIde
of
the

cap
for
d1rt
or
ex

ceSSIve
wear
Look
for

SIgns
of
carbon
tracks
arcmg
from
contact
to
contact
mSIde
the
dIS

trIbutor

cap
Carbon
tracks
mdlcate
defects
or

cracks
and
If
found
the

cap
should
be

replaced

3
Remove
the
rotor
and

mspect
for
exceSSIve

wear
around
the

top
metal
contact

wiper
surface

If

defectlve
replace
As

a
matter
of

good

prac

nce
the

rotor
should
be

replaced
whenever
the

contact

pomts
are

replaced

4
Use
a
screwdriver
to

gently
open
the
contact

pomts
If

they
show
wear
or

plttmg
remove
the

I

7
r

ENGINE
47

allowable

warpage
IS
0
0039
in
0
I
mm

Standard
should
be
less
than
0
0012
in

O
03mm
In
the
event
the
measurements
are

out
of
tolerance
the

cylmder
head
surface

should
be
milled

or
resurfaced

3

Verify
that
all
water
and
011

passages
are
free

of

foreign
matena

Use

compressed
aIr
to
clean

passages
after

scraping

4
Note
the
condition
of
all
studs
in
the

cylinder

head

Replace
damaged
ones

Valve

Assembly

I
Check
intake
and
exhaust
valve
assembhes

for
worn

damaged
or
deformed
valve

caps
and

stems
Correct
or

replace
the
valve
If
excessive

defects
exist

2
Measure
valve
stem
diameter
WIth
a
micro

meter
as
shown
in

Fignre
36

Figure
37

gives

cnncal
drmensions

@

@

Y

lm

1

0
515

r

3
Reface
the
valve
face
and
valve
stem

using
a

valve

grinder
as
18
shown
in

Fignre
38
NOTE

When
the
valve
head

1uzs

been
reduced
to
00197
in
0
Smm

or
less
In
thIckness

replace
the
valve

Grinding
allowance

for
the
valve
stem

end

surface
is
00197
In
0
Smm
or

less

4
Measure
the
free

length
and
tension
of
each

valve

spring
If
the
measured
values
exceed
the

hnuts

specified
below

replace
the

spring

SPRING
SPECIFICATIONS

Free
Length
Outel

Spring

Inner

Spring

Outer

Spring
2
0472
10

52
Omm

1
765710
44
85mm

153m
at6393
331Ib

389mm
at290

15kg

138m
at
2712
154lb

35mm
at12
3
0
7

kg

121
10
at
105
38
5
29
Ib

30
7mm
at
47
8
2
4
kg

09610
at5621
2871b

245mm
at

25
5
13

kg
Valve
Closed

I
nner

Spring

Outer

Spnng

Valve

Open

Inner
Spnng

5
Check
the

deformation
of
each

spnng
with
a

square
Replace
any
spnng
WIth
a
deflection
of

o
063
in
I

611lID
or
more

6
Check
all

workmg
surfaces
of
the
rocker
arms

for

damage
or
wear
If
defects

or

apparent
ex

cessIve
wear

are
found

replace
them
A
defective

PIvot
reqwres
It
S

replacement
along
WIth
the

correspondIng
rocker
ann

7
Measure
the
clearance
between
the

valve

gwde
and
the
valve
stem
If
the
clearance
ex

ceeds
hnuts

replace
the
worn

parts
or
both

CHAPTER
SEVEN

FUEL
SYSTEM

The
fuel

system
mcludes
the

fuel

tank

straIner

pump
carburetor
arr
cleaner
and

necessary
lines

Inspect
components
for
leaks

and
deterioratIOn
whenever
mamtenance
is

done
The
fuel
stramer
should
be

mspected
peri

odIcally
and
cleaned

AIR
CLEANER

The
au
filter
element
is
viscous

paper
and

does
not

require
cleanmg
Replace
It

every

24
000
mlles
or
more

frequently
under
harsh

condItIons

Several
mInor
differences
exist
between

vehicles

dependmg
on
the

type
of
emisSIOn
con

trol
device
used

Figure
1
shows
location
of
the

air
cleaner
on
the

engme
and

parts
compnsing

the
cleaner

system
on
model

years
through
1969

Figure
2
shows
the

changes
for
1970
and
later

Warm
air
is

supplIed
to
the
air
cleaner
from
the

exhaust
mamfold
to

prevent
carburetor

Icmg

AIR
CLEANER
REMOVAL

AND
REPLACEMENT

1
Unthread
the

WIng
nut

atop
the
cleaner

assembly

2
Remove
the
two
bolts

holdIng
the
air
cleaner

to
the

support

3

Disconnect
the

aIr
cleaner
duct
from

the
base

of
the
cleaner
intake
throat
4
LIft
off
the
aIr
cleaner

body
and
remove
the

aIr
filter
as
shown
m

Figure
3

To
remove
the
arr
cleaner

proceed
as
follows

1
Perform

steps
1

through
4
above

2
Unscrew
the
band
bolt
at
the
base
of
the

air
cleaner

3
DIsconnect
all
hoses

leadmg
to
the
air

cleaner

4
Pull

up
on
the

body
of
the
air
cleaner
and

remove
from
carburetor

5

Except
for
the

au
filter

element
thoroughly

clean
all

parts

6
Reverse
the

steps
above
for

reassembly

FUEL
STRAINER

The
fuel
stramer

IS
located
on
the

nght
hand

side
of
the

engme
compartment
Figure
4
shows

the
fuel
stratner
hoses

clamps
and
the
mount

Ing
clIp
that
holds
the
fuel
stramer
In

place
The

fuel
stramer
IS
of
the

cartrIdge
type
and
uses
a

fiber
mat
and

nylon
as

strainer
elements
The

fuel
stramer
should
be

mspected
frequently
for

foreIgn
material
and

replaced
at
least

every

24
000
rmles

1
DIsconnect
the
inlet

and
outlet
hoses
from

the
fuel
stratner
Make
certatn
that
the
mlet
hose

bottom
IS
not

permItted
to
fall
below
the
level

of
the
fuel
tank

or

leakage
wIll
occur

FUEL
SYSTEM
6S

CD

2
Remove
the
fuel
stramer
from
Its

mountlng

clIp

3

Replace
the
fuel
stramer
as

reqUIred

4
Reconnect
the
mtake
and
outlet
fuellmes

FUEL
PUMP

The
fuel

pump
conSISts
of
a

body
rocker
arm

and
lmk

assembly
dIaphragm

dIaphragm

spring
seal
and
mlet
and
outlet
valves
The
l
r

t

1
9

l

F
r

fl

rocker
arm
IS
dnven

by
a

pump
cam
mounted

on
the
catnShaft
In
the
front

part
of
the
rocker

arm
front
cover

assembly

Figure
S
shows
the
fuel

pump
for
all
models

through
1970

Figure
6
illustrates
the

fuel
pump

for
1971
and
later
models

Fuel

pump
Testing

Fuel

pump
pressure
and
fuel

pump
capacity

testlng
are

performed
m
tests
descnbed
below

Both
tests
are

performed
With
the
fuel

pump

mounted
to
the

engme

Static
Pressure
Test

1
DIsconnect
the
carburetor
fuel
lme
at
the

carburetor

2
Install
an

adapter
and
a
tee

fittmg
to
the

fuel
lIne
and
attach

a
SUItable

pressure
gauge

3
Connect

adapter
to
carburetor

4
Start
and
run

engine
at

varymg

speeds

5
The

gauge
reading
IS
static
fuel

pressure
It

should
remam
between
256
and
341
Ib
m
2

018
to
0
24

kg
cm2
Pressure
below
thelower

lImIt
mdlcates
extreme
wear
on
one

part
or

gen

eral

wear
on
several

pump
parts
Pressure
above

the

upper
hrmt
indIcates

an

excessIvely
strong

diaphragm

spnng
or
a

dIaphragm
that
is
too

tIght
Both
condItIons

require
the

removal
of
the

fuel

pump
for

necessary
repaIr
or

replacement