1969 DATSUN 610 oil level

Remove
the
fan

and
pulley
the

right
hand

engine
mounting

and
oil
filter
Remove
the
oil

pressure
switch
Remove
the

following
items
oil
level

gauge
spark
plugs
thermostat

housing

rocker
cover
carburettor
and
inlet
and
exhaust
manifolds

Remove
the
clutch

assembly
as
described
in
the
section

CLUTCH
Remove
the
left
hand

engine
mounting
crankshaft

pulley
water

pump
fuel

pump
fuel

pump
drive
earn
and
cam

shaft

sprocket
See

Fig
A
4
Remove
the

cylinder
head
bolts

in
the

sequence
shown
in

Fig
A

5
and
lift
off
the

cylinder

head
Invert
the
engine
and
remove
the
oil

sump
and
oil

strainer
oil

pump
and
drive

spindle
assembly
front
cover
and

chain
tensioner
Remove
the

timing
chain
oil
thrower
crank

shaft
worm

gear
and
chain
drive

sprocket
See

Fig
A
6
andA
7

Remove
the

connecting
rod

caps
and

push
the

pistons
and

connecting
rods
through
the

top
of
the
bores
as
shown
in

Fig

A
B

Keep
the

connecting
rod

caps
with
their
respective
rods
to

ensure

that

they
are
assembled
in
their

original
positions

Remove
the
flywheel
retaining
bolts
and
withdraw
the

fly

wheel

Fig
A
9
Remove
the
main

bearing
caps
using
the

special
puller
ST
1651
SOOO
to
withdraw
the
centre
and
rear
main

bearing
caps
as
shown
in

Fig
A

l
O
Remove
the
rear
oil
seal

and
lift
out
the
crankshaft
remove
the
baffie

plate
and

cylinder

block
net

Fig
A
II
Remove
the

piston
rings
with
a

suitable

expander
and

press
out
the

gudgeon
pins
under
an
arbor

press

using
the

special
stand
STl300001
as
shown
in

Fig
A

12

Keep

the
dismantled

parts
in
order
so
that

they
can

be
reassembled

in
their

original
positions
Slacken

the
valve
rocker

pivot
lock

nut
and
remove
the
rocker
arms

by
pressing
down
the
valve

springs

Remove
the
camshaft

taking
care
not
to

damage
the

bearings
and
earn
lobes
Withdraw
the
valves

using
the
valve

lifter
STl2070000
as
shown
in

Fig
A
13

ENGINE

Inspection
and
Overhaul

Cylinder
Head
and
Valves

Clean
all

parts
thoroughly
and
remove
carbon

deposits
with

a

blunt

scraper
Remove

any
rust
which
has
accumulated
in

the
water

passages
and
blow

through
the
oil
holes
with

compres

sed
air
to
make
sure

that

they
are

clear

Measure
the

joint
face
of
the

cylinder
head
for
out
of
true

as
shown
in

Fig
A
14

The
surface
should
be
checked
at
various

positions
using
a

straight
edge
and
feeler

gauge
The
permissible

amount
of
distortion
is
0
05
mm
0
0020
in
or
less
If
the

surface
is
out
of
true

by
more
than
the
limit
of
0
1
mm

0
0039

in
it
will
be

necessary
to

regrind
the
head

Clean
each
valve

by
washing
in

petrol
and

carefully
examine

the
stems
and
heads

If
the
stem
is
worn

damaged
or
not

straight
the
valve
must

be
discarded
Check
the

diameter
of
the
stem
with
a
micro

meter

The
diameter
of

the
inlet
valves
should
be
7
965

7
980
mm
0
3136
0
3142
in
and
the
diameter
of

the
exhaust

valves
7
945
7
960
mm
0
3128
0
3134
in

If

the
seating
face
of
the
valve
is

excessively
burned

damaged
or
distorted
it
must
be
discarded
A

badly
pitted

seating
face
should
be
refaced
on
a
valve

grinding
machine

removing
only
the
minimum
amount
of
metal
Renew
the
valve
if
the
thickness
of

the
valve
head
has

been
reduced

by
0
5
mm
0
0197
in
see
Technical
Data
for

valve
dimensions

The

valve
stem

tip

may
be
refaced
if

necessary
the
maxi

mum
allowance
however
is
0
5
mm
0
0197
in

The
valves
can
be

ground
in
to

their
seats
when

completely

satisfactory
The
valve
seats
and
valve

guides
should

be
in

good

condition
and
must
be
checked
as
described
in
the

following

paragraphs

VALVE
GUIDES

Replacement

The
valve
stem
to
valve

guide
clearance
can
be
checked

by

inserting
a
new
valve
into
the

guide
The
stem
to

guide
clearance

should
be
0
020
0
053
mm
0
0008
0
0021
in
for
the
inlet

valves
and
0
040
0
073
mm
0
0016
0
0029
in
for
the
exhaust

valves
If
the
clearance
exceeds
0
1
mm
0
0039
in
for
the

inlet
valves
and
the
exhaust
valves
then
new

guides
should
be

fitted

The
valve

guides
are
held
in

position
with
an
interference

fit
of
0
027
0
049
mm
0
0011
0
0019
in
and
can
be
removed

by
means
of
a

press
and
drift
2
ton

pressure
This
operation

can
be
carried
out
at
room

temperature
but
will
be
more

effectively
performed
at
a

higher
temperature

Valve

guides
are
available
with
oversize
diameters
of
0
2
mm

0
0079
in

if
required
The
standard
valve

guide
requires
a
bore

in
the

cylinder
head
of
11
985
11
996
mm
dia
0
4719

0
4723
in
dia
and
the
oversize
valve

guide
a
bore
of
12
185

12
196
mm
dia
0
4797
0
4802
in

dial

The

cylinder
head

guide
bore
must
be
reamed
out
at

normal
room

temperature

Heat
the

cylinder
head
to
a

temperature
of
150
2000e

302
3920F
before

pressing
in
the
new
valve

guides
Ream

out
the
bore
of
the

guides
to
obtain
the
desired
fInish
and

clearance
Fig
A
IS
The

special
valve

guid
reamer
ST
1103

SOOO
should
be
used
if
available
Valve

guide
inner
diameters

are

specified
in
Technical
Data
at

the
end
of
this
section
The

valve
seat
surface
must

be
concentric
with
the

guide
bore
and

can
be
corrected
with
the

facing
tool
STll670000

Fig
A
16

using
the
new
valve

guide
as
the
axis

VALVE
SEAT
INSERTS

Replacing

The
valve
seat
inserts
should
be
replaced
if

they
show

signs

of

pitting
and
excessive
wear

The
inserts
can
be
removed

by
boring
out
to
a

depth
which

will
cause
them
to

collapse
although
care
must
be
taken
not

to
bore
beyond
the
bottom
face
of
the
recess

in
the

cylinder

head

Select
the
valve
seat

inserts
and
check
the
outer

diameters

Machine
the
recess
in
the

cylinder
head
to

the
following

dimensions
at
room

temperature

9

h
W

and

connecting
rod
assemblies
Use
a

piston
ring

compressor
to

install
the

pistons
through
the

top
of
the

cylbder
bore
Make

sure
that
the

pistons
and

rings
and
the
cylinder
bores
are

lubricated
with
clean

engine
oil
The

pistons
should
be

arranged

so
that
the
F

mark
faces
to

the
front
and
with
the

piston

ring

gaps
positioned
at
1800
to
each
other
Each
piston
must

be
refitted

into
its

original
bore

NOTE

Single
inlet
valve

springs
are
used
on

the
1400
cc

engine
double

valve
springs
are
used
on
the
1600cc

and
1800
cc

engines

Screw
the
valve
rocker

pivots
with
the
locknuts
into
the

pivot
bushing
Set
the
camshaft

locating
plate
and
install
the

camshaft
in
the
cylinder
head
with
the

groove
in
the

locating

plate
directed
to

the
front
of
the

engine
Install
the
camshaft

sprocket
and
tighten
it

together
with
the
fuel

pump
earn
to
a

torque
reading
of
12
16

kgm
86
116
IbJt
a
eck
that
the

camshaft
end
play
is
within

the
specified
limits
Install
the

rocker
arms

using
a
screwdriver
to

press
down
the
valve

springs

and
fit
the
valve
rocker

springs

Gean
the

joint
faces
of
the

cylinder
block
and
head

thoroughly
before

installing
the
cylinder
head
Turn
the
crank

shaft
until
the
No
1

piston
is

at
T
D
C
on
its

compression
stroke

and
make
sure
that
the
camshaft

sprocket
notch
and
the

oblong

groove
in
the
locating
plate
are

correctly
positioned
Care

should
be
taken
to
ensure
that
the
valves
are

clear
from
the

heads
of
the

pistons
The
crankshaft
and
camshaft
must
not
be

rotated

separately
or
the
valves
will
strike
the
heads
of
the

pistons
Temporarily
tighten
the
two

cylinder
head
bolts
1
and

2
in

Fig
A
37
to
a

torque
reading
of
2

kgm
14
5
lb
ft

Fit
the
crankshaft

sprocket
and
distributor
drive

gear
and

install
the
oil
thrower
Ensure
that
the

mating
marks
on
the

crankshaft

sprocket
face
towards
the
front
Install
the

timing

chain

making
sure
that
the
crankshaft
and
camshaft

keys
are

XJinting
upwards
The
marks
on
the

timing
chain
must
be

aligned
with
the
marks
on
the

right
hand
side
of
the
crankshaft

and
camshaft

sprockets
It
should
be
noted
that
three
location

holes
are

provided
in
the
camshaft

sprocket
See

Fig
A
38
The

camshaft

sprocket
being
set
to
the
No
2
location
hole

by
the

manufacturers
A
stretched
chain
will
however
affect
the

valve

timing
and
if
this
occurs
it
will
be

necessary
to
set
the
camshaft

to
the
No
3
location
hole
in
the
camshaft

sprocket
The
chain

can

be
checked

by
turning
the

engine
until
the

No
1
piston
is

at
T
D
C
on
its

compression
stroke
In
this

position
adjustment

will
be

required
if
the
location
notch
on

the
camshaft

sprocket

is
to
the
left
of
the

groove
on
the
camshaft

locating
plate
as

shown
in
the
illustration
The
correction
is
made

by
setting
the

camshaft
on

the
No
3
location
hole
in
the
camshaft

sprocket

the
No
3
notch
should
then
be
to
the

right
of
the

groove
and

the
valve

timing
will
have
to

be
set

using
the
No
3

timing
mark

Install
the
chain

guide
and
chain
tensioner
when
the
chain

is
located

correctly
There
should
be
no

protrusion
of
the
chain

tensioner

spindle
See

Fig
A
39
A
new
tensioner
must
be

fitted
if
the

spindle

protrudes

Press
a
new
oil
seal
into
the

timing
cover
and
fit
the
cover

into

position
using
a
new

gasket
Apply
sealing
compound
to

the
front
of
the

cylinder
block
and
to
the

gasket
and
to
the

top

of

the

timing
cover

Ensure
that
the
difference
in

height
between

the

top
of
the

timing
cover
and
the

upper
face
of
the

cylinder

block
does
not

exceed
0
15
mm
0
006
in
Two
sizes
of

timing

cover
bolts
are

used
the
size
M8
0
315
in
must

be
tightened

to

a

torque
reading
of
1
0
1
6

kgm
7
2
17
Ib
ft
and
the
size
M6
0
236
in
to
a

torque
reading
of
0
4
0
8

kgm

2
9
81b
ft

Install
the
crankshaft

pulley
and
water

pump
tighten
the

pulley
nut
to
a

torque
reading
of

12
16

kgm
86
8
115
7Ib
ft

then
set

the
No
1

piston
at
T
D
C
on
its

compression
stroke

Finally
tighten
the

cylinder
head
bolts
to
the

specified

torque
reading
in
accordance
with
the

tightening
sequence
shown

in

Fig
A
3
The
bolts
should
be

tightened
in
three

stages
as

follows

First

stage

Second
stage

Third

stage
4

kgm
28
9
lbJt

6

kgm
43
4
IbJ
t

6
5
85

kgm
47
0
61
5lb
ft

The

cylinder
head
bolts
should
be

retightened
if

necessary

after
the

engine
has
been
run
for
several
minutes

Install
the
oil

pump
and
distributor
drive

spindle
into
the

front
cover
as
described
under

Engine
Lubrication

System

r
rf

i

Install
the
fuel

pump
water
inlet
elbow
and
front

engine

slinger
Fit
the
oil
strainer
into
position
coat
the
oil

sump

gasket
with
sealing
compound
and
fit
the

gasket
and
oil
sump

to
the

cylinder
block

Tighten
the
oil

sump
bolts
in
a

diagonal

pattern
to

a

torque
reading
of
0
6
0
9

kgm
4
3
6
5
IbJt

Adjust
the
valve
clearances
to
the

specified
cold

engine

ftgures
following
the

procedures
described
under
the

appropriate

heading
Final

adjustments
will

be
carried
out
after
the

engine

has
been
assembled

completely
and
warmed

up
to

its
nonnal

temperature

Install
the
rear

engine
slinger
exhaust
manifold
and
inlet

manifold
Refit

the
distributor
and
carburettor
assemblies
as

described
in
their
relevant
sections

Install
the
fuel

pipes
and

vacuum
hose

making
sure
that

they
are

securely
cl

ped
Refit

the
thermostat

housing
thermostat
and
water
outlet

together

with
the

gasket
Bond
the
rocker
cover

gasket
to
the
rocker

cover

using
sealant
and
fit
the
rocker
cover
to
the

cylinder

head

Install
the
spark
plugs
and
connect
the

high
tension
leads

Fit
the
left
hand

engine
mounting
bracket
and
install
the
clutch

assembly
using
the

alignment
tool
ST20600000
to
fit
the
clutch

to
the

flywheel
as
described
in
the
section
ClUfCR

Lift

the
engine
away
from
the

mounting
stand
and
into

the

engine

compartment
Install
the
alternator
bracket
adjusting

bar
alternator
fan

pulley
fan
and
fan
belt
in
the
order

given

Check
the
tension
of
the
fan
belt

by
depressing
the
belt
at
a

point
midw

y
between
the

pulleys
The

tension
is
correct
if

the
belt
is
deflected

by
8
12
mm
0
3
0
4
in
under
thumb

pressure

Fit
the

right
hand
engine
mounting
bracket
the
oil
filter

oil

pressure
switch
oil
level

gauge
and
water

drain
plug
Take

care
not
to

overtighten
the
oil
nIter
or

leakage
will
occur

Fill
the

engine
and

gearbox
to
the
correct
levels
with

recommended
lubricant

and
refill
the

cooling
system
Adjust

the

ignition
timing
and
carburettor
as
described
in
the

appro

priate
sections

17

VALVE
CLEARANCES

Adjusting

Incorrect
valve
clearance
will
affect
the

performance
of

the

engine
and

may
damage
the
valves
and
valve
seats
Insuf

ficient
valve
clearance
will
result
in
loss
of

power
and

may

prevent
the
valve
from

seating
properly
Excessive
clearance

causes
the
valve
to
seat
and
reduces
the
amount
of

valve
lift

This
will
result
in

noisy
operation
with

damage
to
the
valves

and
seats

Adjustment
is
made
with
the

engine
switched
off

and
should
be
carried
out

initially
with
the

engine
cold
to

allow
the

engine
to
run
Final

adjustments
are
made
after

wanning

up
the

engine
to

its
Donnal

operating
temperature
The

engine
can
be
rotated

by
removing
the

sparking
plugs
to
release

the

cylinder
compressions
then

selecting

top
gear
and

pushing

the
vehicle
backwards
and
forwards

The
cold
valve
clearances
should
be
set
to
0
20
mm

0
0079
in
for
the
inlet
valves
and
0
25
mm
0
0098
in
for

the
exhaust
valves
Check
the
clearance
between
the
valve
and

rocker

using
a
feeler

gauge
as
shown
in

Fig
A
40
Slacken
the

locknut
and
turn
the
adjusting
screw
until
the

specified
clearance

is
obtained
then

tighten
the
locknut
and
recheck
the
clearance

The
feeler

gauge
should

just
be
free
to
move
between
the
rocker

and
valve
When
the
cold
valve
clearances
have
been
set
run
the

engine
until
it
reaches
its
normal

operating
temperature
then

switch
off
and

adjust
the
valve
clearances
with
the

engine
warm

to

0
25
mm
0
0098
in
for
the
inlet
valves
and
0
30
mm

0
0118
in
for
the
exhaust
valves

ENGINE
LUBRICATION
SYSTEM
Fig
A
41

OIL
PUMP
Removal
and

Dismantling

The
rotor

type
oil

pump
is
mounted
at
the
bottom
of
the

front

timing
cover
and
driven

by
the
distributor
drive
shaft

assembly

Overhaul
of
the

pump
will

require
careful
measurement

of

the
various
clearances
to
determine
the
amount

of
wear

which

has
taken

place
If

any
part
is
found
to
be
worn
it

may
be
neces

sary
to

replace
the
entire
oil

pump
assembly
To
remove
the
oil

pump
from
the

engine
proceed
as
follows

1
Remove
the
distributor

assembly
as
described
in
the

section
IGNITION
SYSTEM
Remove
the
oil

sump
drain

plug
and
drain
off
the

engine
oil
See
under
the
heading

CHANGING
THE
ENGINE
OIL

2
Remove
the
front
stabiliser
and
the
splash
shield
board

3
Withdraw
the

securing
bolts
and
detach
the
oil

pump

body
together
with
the
drive

gear
spindle

Take
out
the
bolts
securing
the

pump
cover
to
the

pump
body

and
withdraw
the
rotors
and
drive
shaft
See
Fig
A
42

The
pin
securing
the
driven
shaft
and
inner
rotor
must
not

00
taken
out
as
the
shaft
is

press
fitted
to
the
rotor
and
the

pin

is
caulked

Unscrew
the
threaded

plug
and
withdraw
the
regulator

valve
and

spring
Oean
each

part
thoroughly
and
examine
for

signs
of

damage
or
wear
Use
a
feeler

gauge
to
check

the
side

clearances
between
the
outer

and
inner
rotors
the
clearances

at
the

tips
of
the
rotors
and
the
clearance
between
the
outer

rotor
and
the

pump
body
See
Technical
Data
for
the
relevant

clearances
The
clearances
can

be
checked

using
a

straight
edge

as

shown
in

Fig
A
43

OIL
PUMP

Assembly
and
Installation

Assembly
is
a
reversal
of
the

dismantling
procedure
Before

installing
the
oil

pump
in
the

engine
it
will
be

necessary
to

rotate

the

engine
until
the
No
1

piston
is
at

T
D
C
on

its

compression
stroke

Fill
the

pump
housing
with

engine
oil
and

align
the

punch

mark
on
the

spindle
with
the
hole
in
the
oil

pump
as
shown

in

Fig
A
44

Install
the

pump
with
a
new

gasket
and

tighten
the

securing
bolts
to
a

torque
reading
of
1
1
1
5
kgm
8
1
Ilb
ft

Replace
the

splash
shield
board
and
the
front
stabiliser
refill

the

engine
with
the

specified
amount
of

engine
oil

OIL
FILTER

The

cartridge
type
oil
filter
can
be
removed
with
the

special
tool
ST
19320000
or
a
suitable
filter
remover
Interior

cleaning
is
not

necessary
but
the
ftIter

body
and
element
must

be

repiaced
every
10
000
km
6000
miles
Be
care
ul
not
to

overtighten
the
filter
when

replacing
or

oil
leakage

may
occur

CHANGING
THE
ENGINE
OIL

After
the
fIrst
oil

change
which
should
take

place
at
1000

km
600
miles
the
oil
should
be

changed
regularly
at
5000
km

3000
miles
intervals

Draining
is
more

easily
accomplished
after
a

lengthy
run

when
the
oil

being
thoroughly
warm
will
flow

quite
freely

Stand
the
vehicle
on
level

ground
and

place
a
suitable

container
under
the
drain

plug
Remove
the
drain

plug
carefully

as
the
hot
oil

may
spurt
out
with
considerable
force
When

refIlling
the

engine
make
sure

that
the
oil
is
to
the
H
mark
on

the

dipstick

19

Wear
limit

Crank

pin
journal
diameter

Max
crankpin
taper

Max

crankpin
out
of
round

Thickness
of
main

bearing

shells
0
3
mm
0
012

in

49
961
49
975
mm

1
967
1
9675

in

0
03
mm
0
012
in

0
03
mm
0
012
in

1
827
1
835
mm
0
072
0
0722

in

Main

bearing
running
clearance

0
020
0
062
mm
0
0008
0
0024

in

Max
main

bearing
running

clearance

Crankshaft
bend
limit

Material

Type

Piston
diameters

Standard

I
st
oversize

2nd
oversize

3rd
oversize

4th
oversize

5th
oversize

Width
of

ring
grooves

Top
and
second

Oil
control

Piston

running
clearance
0
12
mm

0
0047
in

0
05
mm
0
002
in

PISTONS

Cast
aluminium

Slipper
skirt

82
99
83
04
mm
3
267
3
269

in

83
22
83
27
mm
3
276
3
278

in

83
47
83
52
mm
3
286
3
288

in

83
72
83
77
mm
3
296
3
298

in

83
97
84
02
mm
3
305
3
308

in

84
47
84
52
mm
3
326
3
328

in

2
0
mm
0
08
in

4
0
mm

0
16
in

0
025
0
045
mm
0
001
0
002

in

PISTON
PIN

Pin
diameter
20
995
21
000
mm
0
8266

0
8268

in

Pin

length
72
00
72
25
mm
2
8346
2
8445

in

Pin

running
clearance
in

piston
0
008
0
010
mm
0
0003
0
0004

in

Pin
interference
fit
in
small
end
bush

0
015
0
033
mm
0
0006
0
0013

in

Piston

ring
height

Top
and
second

Oil
control

Side
clearance
in

grooves

Top
PISTON
RINGS

2
0
mm
0
08
in

4
0
mm
0
16
in

0
040
0
073
mm
0
0016
0
0029

in
Second

Oil
control

Piston

ring
gaps

Top

Second

Oil
control

Material

Distortion
of

sealing
face

Max
distortion

Valve
seat
insert
material

Inlet

Exhaust

Fit

Drive

Chain

Chain
tensioner
0
030
0
063
mm
0
0012
0
0025

in

0
025
0
063
mm
0
001
0
0025

in

0
23
0
38
mm
0
0091
0
0150

in

0
15
0
30
mm

0
006
0
012

in

0
15
0
30
mm
0
006
0
012
in

CYLINDER
HEAD

Aluminium

alloy

0
03
mm
0
0012
in

0
1
mm
0
004
in

Aluminium
bronze

Special
cast

Hot

pressed

CAMSHAFT
DRIVE

From
crankshaft

double
roller

type

Spring
and
oil

pressure
control

Engine
model
lWIN
CHOKE
CARBURE
ITOR

Outlet
diameter

Venturi
diameter

Main

jet

Main
air
bleed

Slow

running
jet

Power

jet

Float
level

Fuel

pressure

Weight

Altitude

setting
main

jet

1000
m
3300
ft
94

2000
m
6600

ft
92

3000
m

10
000

ft
89

4000
m

13
300
ft
87

5000
m

16
600
ft
85
PRIMARY
L13

SECONDARY

30mm

27x
12mm

150

90

180
26
mm

21
x
8
mm

96

80

43

40

23
I
mm
0
905
0
04

in

0
24

kg
sq
em
3
41b

sq
in

2
55

kg
5
61
lb

1

21

and
seats
or
a
weak

diaphragm
return

spring

A

pressure
above
the

specified
figure
may
be
due
to

an

excessively
strong
and
tight
diaphragm

Capacity
test

The

capacity
test
can
be

carried
out
when
the
static

pressure
has
been
tested
and
conforms
with
the

specified
figure

of
0
18

kg
sq
cm
2
6Ib

sq
inJ

Disconnect
the
fuel
line
at

the
carburettor

and

place
a

container
under
the
end
of
the

pipe
to
act
as
a
fuel

sump

Start
the

engine
and
run
it
at
a

speed
of
1000

Lp
m
The

amount

of
fuel
delivered
from
the

pump
in
one
minutc
should

be

1000
cc
2
1
US

pt

If

petrol
does
not
flow
from
the

opcned
end
of

the
pipe

at
the
correct
rate
then
either
the
fuel

pipe
is

clogged
or

the

pump
is
not

operating
correctly

If
the
latter
cause
is

suspected
the

pump
must
be
removed

and

inspected
as
described
below

FUEL
PUMP

Removing
and

Dismantling

Before

removing
the
pump
take
off
the

petrol
tank

cap

and
disconnect
the

pump
inlet
and
outlet

pipes
Blow

through

the

pipes
with

compressed
air
to

make
sure

that

they
are
not

clogged

Remove
the

pump
retaining
nuts

withdraw
the

pump
and

dismantle
it
in
the

following
order

Referring
to

Fig
D
l

Take
out
the
screws

holding
the
two

body
halves

together

and

scparate
the

upper
body
from

the
lower

body

2
Remove
the

cap
and

cap
gasket

3
Unscrew
the
eI
bow
and
connector

4
Take
off

the
valve
retainer
and
remove
the
two
valves

5
To
remove
the

diaphragm
diaphragm
spring
and
lower

body
sealing
washer

press
the

diaphragm
down

against

the
force
of
the

spring
and
tilt
the

diaphragm
at
the
same

time
so
that
the

pull
rod
can
be
unhooked
from
the
rocker

arm

link

Fig
D
7

The
rocker
arm

pin
can

be
driven
out
with
a
suitable

drift

FUEL
PUMP

Inspection
and

Assembly

Check
the

uppcr
and

lower

body
halves
for
cracks

Inspect

the
valve
and
valve

spring
assembly
for

signs
of
wear
and
make

sure
that
the

diaphragm
is
not

holed
or

cracked
also
make
sure

that
the
rocker
arm
is
not
worn
at
the

point
of
contact
with

the

camshaft

The
rocker
arm

pin
may
cause

oil

leakage
if
worn

and

should
be
renewed
Assembly
is
a
reversal
of
the
dismantling
procedure

noting
the

following
points

Fit
new

gaskets
and
lubricate
the
rocker
arm
link
and
the

rocker
arm

pin
before

installing

The

pump
can
be
tested

by
holding
it
approximately
I

metre
3

feet
above

the
level
of
fuel

and
with
a

pipe
connected

between
the
pump
and
fuel
strainer

Operate
the
rocker
ann

by
hand
the

pump
is

operating

correctly
if
fuel
is
drawn

up
soon
after

the
rocker
ann
is

released

CARBURETTOR
IDLING
ADJUSTMENT

The

idling
speed
cannot
be

adjusted
satisfactorily
if
the

ignition
timing
is
incorrect

if
the
spark
plugs
are

dirty
or
if

the
valve
clearances
are
not

correctly
adjusted

Before

adjusting
the

idling
speed
set
the
hot
valve

clearances

t
o
0
25
mm
0
0098
in
for
the
intake
valves

and

0
30
mm
0
0118
in
for
the
exhaust
valves
as
described
in

the
ENGINE

section

Idling
adjustment
is
carried
out

with
the
throttle

stop

screw
in

conjunction
with
the

idling
adjustment
screw

See

Fig
D
8

Run
the

engine
until
it
attains
its
normal

operating

temperature
and
then
switch
off

Starting
from
the
fully
closed

position
unscrew
the

idling
adjustment
screw

by
approximately
three
turns

Screw
the
throttle

stop
screw
in

by
two
or
tftr
e
turns
and

start

th
engine

Unscrew
the
throttle

stop
screw
until
the

engine
commences

to
run

unevenly
then
screw
in
the

idling
adjustment
screw
so

that
the
engine
runs

smoothly
at
the

highest
speed

Readjust
the
throttle

stop
screw
to

drop
the

engine
speed

of

approximately
600
r

p
m
is
obtained

WARNING
Do
not

attempt
to
screw

the

idling
adjustment

screw

down
completely
or
the

tip
of
the
screw

may
be

damaged

FAST
IDLE
OPENING
ADJUSTMENT

The
choke
valve
is

synchronized
with
the
throttle
valve

and
connected
to
it

by
levers
as
shown
in

Fig
D
9
The
fast

idle
opening
can
be
check

by
fully
closing
the
choke
valve
and

measuring
the
clearance
between
the

primary
throttle
valve
and

the
wall
of

the
throttle
chamber
This
clearance

being
shown

as
A

in
the
illustration
The
clearance
for

the
carburettor

types
is
as
follows

Carburettor

type
Throttle

opening

angle

180

180

190
Dimension
A

213304
361

13304
4
I

13282
331
1
55mm
0
06lin

1
55mm
0
06Iin

1
3
mm
0
051
in

35

FLOAT
LEVEL

Adjustment

A
constant
fuel

level
in
the
float

chamber
is
maintained

by

the
float
and
ball
valve

Fig
D
12
If
the
fuel
level
is
not

in

accordance
with
the
level

gauge
line
it
will
be

necessary
to
care

fully
bend

the
float
seat
until
the
float

upper
position
is

correctly

set

Fig
D
13

The
clearance
H
between
the
valve
stem

and
float
seat

should
be
1
0
mm
0
039
in
with
the
float

fully
lifted
as
shown

Adjustment
can

be
carried
out

by
carefully
bending
the
float

stopper
Fig
D
14
until
the

required
clearance
is
obtained

SU
TWIN
CARBURETTORS

Adjustments

It
is
essential
that
the
two

carburettors
are

correctly
adjusted

if

peak
m3l1ce
and
economical
fuel

consumption
is
to
be

realized
Incorrect
carburettor

a
ljustment
will
have
an
adverse

affect

during
idling
and
on

acceleration
etc

Carburettor

synchronization
and

idling
adjustment

Run
the

engine
until
it
reaches
its
normal

operating

temperature
remove
the
air
cleaner
and
slacken

the
front

and

rear
throttle

adjusting
screws
the
balance
screw
and
the
fast

idling
setting
screw
Make
sure
that
the
front
and
rear
throttle

shafts
are
not
connected

Fully
tighten
the

idling
adjustment

nuts
of

the
front

and
rear

carburettors

Fig
D
15

the
back

off
each
nut

by
an

equal
amount
and

by
one
and
a
half
to
two

tUrns

Screw
in
the
front
and
rear
throttle

adjusting
screws

by
a

few
turns
and
start
the

engine
Allow
the

engine
to
reach
its

normal

operating
temperature
before

proceding
to

the
next

stage

Adjust
the
front
and
rear
throttle

adjusting
screws
until

the

engine
speed
is
reduced
to

approximately
600
700
r

p
m

The

engine
should
turn
over

smoothly
and

consistently
Apply

a

flow
meter
to
the
front
carburettor
air
cleaner

flange
and
turn

the

adjustment
screw
on
the
flow
meter
so
that
the

upper
end

of
the
float
in
the

glass
tube
is
in

line
with
the
scale
Uft
off
the

flow
meter

and
apply
it
to

the
rear
carburettor
air
cleaner

flange

without

altering
the

setting
of
the
flow
meter

adjusting
screw

If

the

position
of
the
flow

meter
float
is
not

aligned
with
the

scale

adjust
the
rear
carburettor

throttle
adjusting
screw
to

align
the
float
with
the
mark
on
the
scale

With
the
carburettor
flow

correctly
adjusted
turn
the

idling
adjustment
nuts

of
both
carburettors

approximately
1
8

of

a
turn

either
way
to
obtain

a
fast

and
stable

engine
speed

Both
nuts
must

be
turned

by
an

equal
amount

Back
off
the
front
and
rear
throttle

adjusting
screws
and

adjust
the

engine
speed
to

the

specified
value
of

650
r

p
m

for

the
standard

engine
or
700
r

p
m
with
vehicles
fitted
with

automatic
transmission
Make
sure

that
the
air
flow
of

both

carburettors
remains

unchanged
Screw
in
the
balance
screw

until
the
screw
head
contacts
the

throttle
shafts
without

changing
the

idling

speed
setting

Move
the
throttle

connecting
shaft
and
accelerate
the

engine
a
few
times
then
check
that
the

idling
speed
is

unchanged

Turn
the
fast
idle

setting
screw

to
increase
the

engine
speed

to

approximately
1500

r

p
m
and
recheck
with
the
flow
meter
that
the
air
flow
for
both
carburettors
is

correctly
matched
If

the
air
flow
is
uneven

it
will
be

necessary
to

readjust
the
balance

screw

Finally
back
off

the
fast
idle

setting
screw

Fig
D
16

and
decrease
the

engine
speed
Apply
the
flow
meter
to

the

carburettors
to
confirm
that
the
float

positions
are
even
Re

adjust
if

necessary
by
means
of

the
throttle

adjusting
screws

Stop
the

engine
and
fit
the
air
cleaner

SU
TWIN
CARBURETTOR

Dismantling

Piston
and
suction
chamber

Dismantling

Unscrew
the
plug
and
withdraw
the

piston
damper
Fig
D

17
Remove
the
four
set
screws

and
lift
out

the
suction

chamber
withdraw
the

spring
nylon
washer
and
the

piston

Take
care
not
the

damage
the

jet
needle
and
the
interior
of

the

suction
chamber

Do
not
remove
the

jet
needle
from
the

piston
unless

absolutely
necessary
If
a

replacement
is
to
be
fitted
ensure
that

the
shoulder
of
the
needle
is
flush
with
the
lower
face
of

the

piston
This

operation
can

be
accomplished
by
holding
a
strai

edge
over
the
shoulder
of
the
needle
and
then

tightening
the

set
screw
as
shown
in
Fig
D
18

Wash
the
suction
chamber
and

piston
with
dean
solvent

and

dry
with

compressed
air
Lubricate
the
piston
rod
with
a

light
oil
Do

NOT
lubricate
the

large
end
of
the

piston
or
the

interior
of
the
suction
chamber

NOZZLE

Dismantling

The
nozzle
See
Fig
D
19
can
be
removed

quite
easily

but
should
not
be
dismantled
unless

absolutely
necessary
as

reassembly
of

the
nozzle
sleeve
washer
and
nozzle
sleeve

set
screw
is
an

extremely
intricate

operation

To
remove
the
nozzle
detach
the

connecting
plate
from

the
nozzle
head

pulling
lightly
on

the
starter
lever
to
ease
the

operation
Loosen
the

retaining
clip
take
off
the
fuel
line
and

remove
the
nozzle
Be
careful
not
to

damage
either
the
jet

needle
oc

the
nozzle
Remove
the
idle

adjusting
nut
and

spring

The
nozzle
sleeve
can
be
removed
if

necessary
by
taking
out

the
set
screw
but
as
previously
stated
should
not
be
dismantled

unless

absolutely
necessary

SU
TWIN
CARBUREfTOR

Assembly

Assemble
the

piston
assembly
into

position
but
do
not

fill
with

damper
oil

Assemble
the
nozzle
sleeve
washec
and
set
screw

by

temporarily
tightening
the
set
screw

Set
the
piston
to
its

fully

closed

position
and
insert
the
nozzle
until
it
contacts

the
nozzle

sleeve
When

the
nozzle

jet
contacts
the

jet
needle
the
nozzle

sleeve
must
be

slightly
adjusted
so

that
it
is
at

right
angles
to
the

centre
axis

and
positioned
to
leave
the
nozzle

jet
clear
of

the

jet
needle
Raise
the

piston
without

disturbing
the
setting
and

allow
it
to

drop
The

piston
should

drop
smoothly
until
the

stop
pin
strikes
the
venturi
with
a

liaht
metallic
click
See
below

under

Centering
the

jet
Tighten
the
nozzle
sleeve
set
screw

remove
the

nozzle
install
the
idle

adjustinJ
spring
and

adjusting

nut
on
the
nozzle
sleeve
and
refit
the
nozzle

39

1

Oil
cap
nut

2
Suction

chomber

3
Suction

piston

4

Li

tingpin

S

Stop
pin

6
Oil

dDmper

7

Plunger
3

j

I

r

L
2

1

Fig
0
17

Inspecting
the

suction

piston

STlq
O

OO

Fig
D
20

Checking
the
float
level
SU

twin
carburettors

q
J

iT

j

I

@

@

J
1
Conn

ctingrod

2

Wi
guard

3
Choke

lever

4

Connecting
plate

7
S
Thrott

adjusting
SC
Tt
W

6
Fast
id
lever

7

Throttle

adjusting
p1at

8
Throttle

valv

9

Throttlevalv
cletlran

B

Fig
D
22

Adjusting
the

starting
interlock

opening
inteN
lli
i

D

U
I

i

n

1
Jet
n
edle

2
Set
screw

Fig
D
18

Installing
the

jet
needle

1
Nozzle
sleeve

2
Wa
sher

3
Nozz
det
V
d
C1e
W

4

Ad
u
ting
him

5

dlingadjustment
spring

6

Idling
adjustment
nut

Z
Nozz
c
J

Fig
D
l9

Dismantling
the
nozzle

assembly

3

I
Float
lever

2
Bend
here

loadju5t

dimension
H

3
Va
veslem
r

F

Fig
D
21

Adjusting
the
float

level
SU

twin
carburettors

Fig
D
23

Checking
the

damper
oil

41

Connect
the
fuel
line
from
the
float

chamber
to
the
nozzle

nipple
and

tighten
the

retaining
clip
Pull
out

the
choke
lever

and

place
the

connecting
plaie
betw
n
the
washer
and
sleeve

collar
Screw
the

plate
to
the

nozzle
head
and
check
that
the

collar
is
installed
in
the
hole
in

the

plate
by
mo

ing
the
choke

lever
as

necessary

Recheck
the

piston
to
make

sure
that
it
falls

freely
without

binding

SU
TWIN
CARBURETTOR

Centering
the

jet

Remove
the

damper
oil

cap
nut

and
gradually
raise
the

lifter

pin
4
in

Fig
D
17

Continue
to
raise
the
lifter

pin
until
the
head
of
the

pin

raises
the

piston
by
approximately
8
mm
0
31
in
When
the

lifter

pin
is
released
the

piston
should

drop
freely
and
strike

the
venturi
with
a

light
metallic
click
If

the

pi
ston
does
not

fall

freely
it
will
be

necessary
to
dismantle
the

carburettor
in

the
manner

previously
described

SU

TWIN
CARBURETTOR

FLOAT
LEVEL

Inspection
and

Adjustment

The
fuel
level
in
the
float
chamber
can

be
checked

using

the

special

gauge
ST
19200000
Remove
the
float
chamber

drain

plug
and
install
the

special

gauge
as
shown
in

Fig
D
20

Start
the

engine
and
allow
it
to
run
at

idling
speed
The

fuel
level
is
conect
if
it
is

indicated
on

the

glass
tu

be
at
a

distance
of
22
24
mm
0
866
0
945
in
below
the

top
of
the

float
chamber

The
level
of
the
fuel
can

be
corrected
if

necessary
by

adjusting
the
float
level
in
the

following
manner
Take
out
the
float
chamber
coveT

securing
screws
and

lift
off
the
cover
and
attached
float

lever
Hold
the
cover
so
that

the
float
lev
r
is

facing
upwards
Lift
the
float
lever
and
then

lower
it
until
the
float
lever
seat

just
contacts

the
valve
stem

The
dimension
uH
in

Fig
D
1
should
be
11
12
mm
0
43

0
47
in

and
can

be
corrected

by
bending
the
float
lever
at
the

point
indicated

SU
TWIN
CARBURETTOR

Starting
interlock
valve

opening
adjustment

To

adjust
the
starting
interlock

opening
the

connecting

rod
4
in

Fig
D
22
1
must
be
bent

using
a
suitable

pair
of

pliers
The
throttle

opening
can

be
increased

by
lengthening

the

connecting
rod
or
reduced

by
shortening
the
rod

The
throttle

opening
is
correctly

adjusted
when
the

clearance
8

between
the
throttle
valve
and
throttle
chamber

is
set
to
0
6
mm
0
023
in
with
the
choke
lever
half

completely

out

HYDRAULIC
DAMPER

The

damper
oil

should
be
checked

approximately
every

5000
km
3000
miles
To
check
the
oil
level
remove
the
oil

cap
nut
as
shown

in

Fig
D
23
and
check
the
level
of
oil

against

the
two

grooves
on
the

plunger
rod

Top

up
with
SAE
20

engine
oil
if

the
oil
level
is
below
the
lower
of
the
two

grooves

Take
care

not
to
bend
the

plunger
rod
when

removing
and

replacing
the
oil

cap
nut

and
make
sure
that
the
nut
is

sufficiently

tightened
by
hand

TechnIcal
Data

Engine
Model
Ll4

I400cc

Primary
Secondary

28mm
32mm

21x7mrn
28xlOmm

96

165

60
60

I
Omm

220
100

1
6
Outlet
diameter

Venturi
diameter

Main

jet

Main
air
bleed

1
st

slow
air
bleed

2nd
slow
air
bleed

Economizer

Power

jet

Float

level

Fuel

pressure

Main
nozzle
55

22mm

0
24

kg

sq
cm
3
41b

sq
in

2
2mm

2
Smm

SU
Twin
Carburettors

Type

Bore
diameter

Piston
lift

Jet
needle

Nozzle

jet
diameter

Suction

spring
IUL
38
W6

38mm

1
4961
in

29mm

1417
in

M
76

2
34
mm

0
0921
in

No
23

Float
needle
valve

inner
diameter

Float

level
1
5mm
0

059
in

23mm
0
9055
in

42
Ll6
1600cc

Primary

Secondary

28mm
32mm

22x7mm

29xlOmm

102
165

60

60

1
0mm

180
100

1
6
Ll8

l80Occ

Primary
Secondary

30mm

34mm

23x14x7mm
30xlOmm

102
170

60
60

I
Omm

210
100

1
6

55

22mm
55

22m

2
3mm
2
5mm
2
3mm
2
8mm

Throttle

clearance
at
full

throttle

Position
at
full
throttle
0
6mm
0
0236
in

6
50

FUEL
PUMP

Type

Delivery
amount
Mechanical

1000cc
minute
at
1000

r

p
m

0
18
0
24

kg

sq
cm

2
5
3
41b

sq
in

from
eccentric
on
cam

shaft
Delivery

pressure

Drive