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INSTRUCTIONS

FOR

0.S.

FS-'70S

FOUR

STROKE

CYCLE

ENGINE

IMPORTANT:

Before

attempting

to

operate

your

FS-705,

please

read

through

these

instructions

so

as

to

familiarize

yourself

with

the

controls

and

other

features

of

the

engine.

Also,

pay

careful

attention

to

the

recommendations

con-

tained

in

the

“Safety

Instructions

and

Warnings”

leaflet

enclosed.

INSTALLATION

Use

sturdy

engine

mounting

beams:

i.e.

at

least

as

strong

as

would

be

used

for

a

two-stroke

engine

of

15cc,

or

greater,

displacement.

Make

sure

that

these

beams

are

firmly

integrated

with

the

airframe,

reinforcing

the

internal

sur-

rounding

structure

as

necessary

to

absorb

vibration.

Engine

installation

should

be

made

in

such

a

way

that

basic

main-

tenance,

including

the

checking

and

adjustment

of

valve

clearances,

can

be

conveniently

carried

out.

As

an

aid

to

aligning

the

engine

on

its

mounting

beams,

a

simple

mount-

ing

hole

template

is

supplied

with

the

engine.

As

an

alternative

to

horizontal

beam

mounting,

a

special

O.S.

radial

motor

mount

is

available,

as

an

optional

extra

part,

for

use

where

firewall

mounting

is

required.

SILENCER

ASSEMBLY

Installation

procedure

is

as

follows.

1.

Screw

the

exhaust

header

pipe

into

the

exhaust

port

until

it

“bottoms”,

then

unscrew

it

just

sufficiently

to

achieve

the

required

exhaust

outlet

angle.

Secure

the

pipe

in

this

position

by

tightening

the

locknut

firmly

against

the

cylinder

head

with

the

wrench

supplied.

2.

Screw

the

silencer

onto

the

end

of

the

header

pipe

and

tighten

locknut

firmly.

Note:

It is

advisable

to

apply

silicone

sealant

at

the

joints

to

prevent

leakage

of

exhaust

gas

and

loosening

of

nuts.

lg

1

aaa

An,

hie

le!

alate

CARBURETTOR

THROTTLE

The

needle-valve

and

throttle

lever

locations

are

inter-

changeable

by

reversing

the

carburettor.

This

can

be

done

as

follows:

Remove

the

carburettor

carefully

by

unscrewing

the

two

screws

which

secure

both

carburettor

and

choke

valve.

(See

Photo

1.)

If

the

carburettor

remains

difficult

to

remove,

slightly

loosen

the

two

screws

which

secure

the

intake

pipe

to

the

cylinder

head.

After

reversing

the

carburettor,

re-insert

it

into

the

intake

pipe

gently,

taking

care

not

to

damage

the

O-ring

in

the

carburettor

by

using

force.

Intake

pipe

Ha

Nid

ring

Carburettor

fixing

screws

Set

screw

i

Mee

lever

Hexagon

nut

Cap

screw

Choke

rubber

pad

Photo

1

CHOKE

VALVE

|

The

FS-70S

is

equipped

with

a

spring-loaded

choke

valve.

The

choke

valve

operating

lever

can

be

located

right

or

left

by

transposing

the

hexagon

nut

and

cap

screw.

After

mounting

the

engine

in

the

model,

secure

the

L-shaped

choke

rod

by

tightening

the

set-screw.

If

the

rod

supplied

is

too

long,

reduce

it

to

the

required

length.

If

the

rod

length

is

more

than

40mm

(1%

in.)

its

outer

end

should

be

supported

to

avoid

vibration.

SPECIFICATIONS

11.50

cc

(0.702

cu.in.)

25.8

mm

(1.016

in.)

22.0

mm

(0.866

in.)

2,000

~

12,000

r.p.m.

Displacement

Bore

|

Stroke

Practical

R.P.M.

Output

1.1

BHP/11,000

r.p.m.

Weight

570

g

(20.1

oz.)

FUEL

TANK

The

suggested

fuel

tank

size

is

270cc

or

9%

oz.

This

will

give

approximately

12

minutes

running

time

when

some

part-throttle

operation

is

included.

Locate

the

fuel

tank

so

that

the

centre

line

of

the

tank

is

10

to

15mm

below

the

centre

line

of

the

needle-valve.

Note:

If

the

model

is

left

unattended

with

the

fuel

tank

filled,

fuel

may

flow

into

the

carburettor,

causing

it

to

“flood”

and

making

the

engine

difficult

to

start.

Take

appropriate

action

to

prevent

this.

FUEL

The

FS-70S

runs

on

standard

commercially

available

model

glowplug

engine

fuel.

Fuels

containing

castor-oil

and/or

synthetic

lubricants

are

acceptable,

but

for

the

best

per-

formance

and

reliability,

a

fuel

containing

5

—

15%

nitro-

methane

is

recommended.

For

consistent

performance

and

long

engine

life,

it

Is

advisable

to

use

good

quality

fuel

containing

16

to

20%

lubricant.

(The

carburettor

is

adjusted

with

a

fuel

containing

20%

lubricant

when

the

engine

leaves

the

factory.)

(|

Centre

line

nla

GLOWPLUG

An

O.S.

Type

“F”

glowplug

is

fitted

to

the

engine.

With

a

four-stroke

engine,

ignition

of

the

fuel

charge

takes

place

at

every

fourth

stroke

of

the

piston

instead

of

every

second

stroke.

Because

of

this,

some

conventional

two-

stroke

glowplugs

will

not

suit

this

engine.

For

general

use,

the

special

O.S.

Type

F

glowplug

is

recommended.

PROPELLER

The

choice

of

propeller

depends

on

the

design

and

weight

of

the

model

and

on

the

type

of

flying

envisaged.

Deter-

mine

the

best

size

and

type

after

practical

experiment.

As

starting

points,

suggested

propellers

are

listed

below.

For

sport

&

stunt

models

11x8

~

9,12x7

~8

12%

XG

13%x8,

14x7,

11x7

(3-blade)

For

scale

models

12x8

(3-blade),

12%x7

(3-blade)

Note:

Smaller

or

larger

props

than

those

shown

in

the

list

can

be

used.

However,

it

should

be

noted

that

propeller

noise

will

increase

as

the

r.p.m.

increase.

For

safety,

keep

your

face

and

other

parts

of

the

body

wel!

away

from

the

propeller

when

starting

the

engine

or

adjust-

ing

the

needle-valve

while

the

engine

is

running.

Remember

that

the

propeller

turns

through

a

much

wider

arc

with

the

large

sized

propellers

that

this

engine

is

capable

of

driving.

Refer

to

the

“Safety

instructions

and

Warnings”

leafiet

enclosed.

IMPORTANT:

Use

well

balanced

propeilers

and

spinners

only.

An

unbalanced

propeller

or

spinner

causes

vibration

and

loss

of

power.

WARNING:

There

is

always

a

danger,

especially

with

nylon

pro-

pellers

(and

depending

on

engine

speed

and

weather

conditions),

of

the

propeller

fracturing

and

a

blade

flying

off

and,

obviously,

this

could

cause

serious

injury.

Therefore,

never

crouch

over

the

engine

when

it is

running

and

keep

all

onlookers

well

back

and

behind

the

model.

If

a

spinner

is

used,

make

sure

that

the

spinner

notches

are

large

enough

to

clear

the

propeller

blades

and

so

do

not

cut

into

and

weaken

the

blade

roots

when

the

propeller

nut

is

tightened.

There

is

also

a

risk,

particularly

with

four-stroke

engines,

of

the

propeller

flying

off

if

the

propeller

nut

loosens

due

to

detonation

or

knocking"

when

the

engine

is

run

too

lean

or

under

too

heavy

a

load.

Obviously

this

can

also

be

very

hazardous.

To

combat

this

danger,

we

have

developed

the

special

Safety

Propeller

Locknut

Assembly

supplied

with

the

FS-70S.

This

prevents

the

propeller

from

flying

off,

even

if

the

propeller

itself

should

slip

or

loosen.

1.

Ream

the

propeller

centre

hole

to

8mm

dia.

Make

sure

that

the

propeller

is

properly

balanced.

2.

Fit

the

propeller

sleeve-nut

and

washer

to

the

propeller,

screw

onto

the

shaft

and

tighten

firmly

with

14mm

wrench

supplied.

3.

Finally,

insert

the

Safety

Propeller

Locknut.

Tighten

Locknut

firmly

(but

not

with

excessive

force)

using

12mm

wrench.

(see

Fig.

2)

Propeller

washer

IMPORTANT:

Regardless

of

the

type

of

propeller

fixing

used,

make

a

habit

of

al-

ways

checking

the

tightness

of

the

propeller

before

starting

the

engine.

Remember

that,

especially

with

wooden

propellers,

there

is

a

tendency

for

the

material

to

shrink,

or

for

it

to

be

reduced

by

the

serrated

face

of

the

drive

hub.

STARTING

It is

preferable

to

use

a

heavy-duty

electric

starter,

although

hand-starting

is

also

possible,

as

will

be

explained

in

a

moment.

1.

Firstly,

fit

a

spinner

so

that

an

electric

starter

can

be

used.

The

O.S.

special

locknut

set

for

spinner,

that

is

available

as

an

optional

part,

enables

you

to

fit

a

spinner

securely

and

easily.

2.

Open

the

throttle

so

that

the

throttle-arm

is

at

one-

Starting

position

quarter

of

its

full

throw.

Fig.

3

(see

Fig.

3).

(a)

lf

a

silencer

pressurized

fuel

system

is

employed,

set

the

needle-valve

2

to

2%

turns

open

from

the

fully

closed

position.

(b)

If

a

silencer

pressurized

fuel

system

is

not

employed,

set

the

needle-valve

3

to

4

turns

open

from

the

fully

closed

position.

3.

Energize

the

glowplug

and

apply

the

electric

starter

after

making

sure

that

the

battery

leads

are

properly

connected

for

counter-clockwise

rotation.

If

the

power

of

your

starter

is

insufficient

to

immediately

rotate

the

engine

freely,

turn

the

propeller

clockwise

(‘backwards’)

until

compression

is

felt,

then,

with

the

propeller

in

this

posi-

tion,

try

the

starter

again.

This

will

enable

the

kinetic

Drive

washer

Propeller

nut

Locknut

Fig.

2

energy

of

the

rotating

propeller

to

assist

in

carrying

the

engine

through

its

compression

stroke.

Also,

make

sure

that

your

starter

battery

is

in

good

condition

and

fully

charged.

CAUTION:

Never

apply

an

electric

starter

with

the

choke

closed.

Such

an

action

will

cause

an

excess

quantity

of

fuel

to

be

drawn

into

the

cylinder

and

result

in

hydraulic

tock

that

may

damage

the

engine.

4.

When

the

engine

starts,

keep

it

running,

initially,

with

the

original

needle-valve

setting

while

steadily

moving

the

throttle

to

the

fully

open

position.

If

the

engine

slows

down

because

the

mixture

is

excessively

rich,

close

the

needle-valve

slowly

until

the

engine

runs

evenly.

Then

disconnect

the

battery

from

the

glowplug

and

close

the

needle-valve

slowly

so

that

revolutions

increase.

Adjust

the

needle-valve

gradually.

Abrupt

adjustment

of

the

needle-valve

may

cause

the

engine

to

stop.

The

above

starting

procedure

is

standard

for

the

FS-/0S.

However,

the

engine

may

be

safely

hand

started

—

except

when

using

a

lightweight

wooden

propeller.

For

safety,

be

sure

to

use

a

‘‘chicken-stick’’.

The

procedure

is

as

follows.

1.

The

propeller

should

be

fixed

in

such

a

way

that

it

is

positioned

horizontally

as

compression

is

first

felt

when

turning

the

propeller

counter-clockwise.

2.

Open

the

throttle

so

that

the

throttle-arm

is

at

one-

quarter

of

its

full

throw.

(See

Fig.

3)

(a)lf

a

silencer

pressurized

fuel

system

is

employed,

set

the

needle-valve

2

to

2%

turns

open

from

the

fully

closed

position.

(b}

If

a

silencer

pressurized

fuel

system

is

not

employed,

set

the

needle-valve

3

to

4

turns

open

from

the

fully

closed

position.

3.

Prime

the

engine

by

closing

the

choke

valve

and

turning

the

propeller

through

4

to

5

revolutions,

depending

on

the

length

of

pipe

from

tank

to

carburettor.

4.

Turn

the

propeller

counter-clockwise

several

times

so

that

fuel

is

drawn

well

into

the

cylinder.

5.

Gradually

turn

the

propeller

counter-clockwise

until

compression

is

felt.

Leave

the

prop

at

this

position.

6.

Recheck

the

throttle

setting

(approx.

quarter

open).

7.

Connect

the

glowplug

battery

and,

using

the

chicken-

stick,

briskly

swing

the

propeller

clockwise

from

the

position

determined

above

and

from

the

centre

of

the

right

blade.

The

engine

wil!

then

bounce

smartly

in

the

counter-clockwise

direction

to

the

point

where

ignition

and

expansion

of

the

charge

takes

place.

If

the

engine

stops,

make

sure

that

fue!

is

reaching

the

carburettor

from

the

fuel

tank,

then

repeat

procedures

3)

to

7).

Correct

priming

is

the

secret

of

easy

hand-starting.

8.

When

the

engine

starts,

keep

it

running,

initially,

with

the

original

needle-valve

setting.

If

it

slows

down

because

the

mixture

is

excessively

rich,

close

the

needle-valve

slowly

until

the

engine

runs

evenly.

Then

disconnect

the

battery

from

the

glowplug

and

close

the

needle-valve

slowly

so

that

revolutions

increase.

Adjust

the

needle-

valve

gradually.

Abrupt

adjustment

of

the

needle-valve

may

cause

the

engine

to

stop.

9.

To

re-start

the

engine

when

it

is

hot,

after

a

run,

first

try

just

flipping

the

propeller,

with

the

throttle

in

the

idling

position,

after

re-energising

the

glowplug.

If

the

engine

does

not

re-start,

re-prime

it

by

closing

the

choke

valve

while

rotating

the

propeller

once

or

twice

until

the

cylinder

becomes

cool

enough

for

restarting.

CAUTION:

Do

not

connect

the

glowplug

to

the

battery

while

priming.

Note:

Excess

fuel

in

the

carburettor

may

drip

into

the

engine

com-

partment

when

the

choke

valve

is

reopened.

Therefore,

it

is

advisable

to

drill

a

drain

hole

in

the

bottom

of

the

engine

bay

,

or

cowling

and

to

apply

fuelproof

paint

to

the

surrounding

surfaces

to

prevent

fuel

from

penetrating

the

airframe

struc-

ture.

RUNNING-IN

(“Breaking-in’’)

All

internal

combustion

engines

benefit,

to

some

degree,

from

extra

care

when

they

are

run

for

the

first

few

times

—

known

as

running-in

or

breaking-in.

This

is

because

the

working

parts

of

a

new

engine

take

a

little

time

to

settle

down

after

being

subjected

to

high

temperatures

and

stress.

However,

as

O.S.

engines

are

made

with

the

aid

of

the

finest

modern

precision

machinery

and

from

the

best

and

most

suitable

materials,

only

a

very

short

and

simple

running-in

procedure

Is

required

and

can

be

carried

out

with

the

engine

installed

in

the

model.

For

running-in,

use

the

same

sized

propeller

as

you

intend

for

flying

your

model.

Running-in

procedure

is

as

follows:

Start

the

engine

and

run

it

for

about

5

seconds

at

around

maximum

r.p.m.,

then

open

the

needle-valve

%2

turn

to

produce

a

rich

mixture

for

cooler,

slower

running,

and

run

for

20

seconds

at

this

setting.

Keep

the

throttle

fully

open,

using

only

the

needle-valve

to

reduce

speed.

Repeat

this

procedure,

alternately

running

the

engine

fast

and

slow

with

the

needle-valve,

but

gradually

extending

the

short

periods

of

maximum

speed

running

until

two

full

tanks

of

fuel

are

consumed.

Note:

Take

care

to

avoid

dusty

and

sandy

locations.

Dust

and

grit

drawn

into

the

engine

will

seriously

damage

its

working

parts.

Following

the

initial

running-in

on

the

ground,

the

engine

should

be

given

a

period

of

moderately

rich

running

in

the

air.

For

the

first

flights,

set

the

needle-valve

rich,

consistent

with

adequate

take-off

power

and

steady

level

flight

and,

if

necessary,

readjust

the

throttle

trim

on

the

transmitter

so

that

the

engine

does

not

stop

when

the

throttle

is

fully

closed.

With

each

successive

flight,

close

the

needle-valve

slightly,

until,

at

the

end

of

10

flights,

the

needle-valve

is

set

for

maximum

power.

The

carburettor

can

now

be

adjusted

for

optimum

throttle

performance

following

the

instructions

given

tn

the

next

section.

Note:

Remember

that,

while

the

engine

is

being

run-in

and

the

needle-valve

is

set

on

the

rich

side,

the

carburettor

cannot

be

expected

to

show

its

best

response.

Therefore,

avoid

abrupt

throttle

operation

at

this

stage.

ADJUSTING

THE

CARBURETTOR

The

carburettor

of

your

FS-70S

has

been

factory

set

for

the

approximate

best

result,

but

the

settings

may,

in

some

cases,

vary

slightly

in

accordance

with

fuel

and

climatic

conditions.

If

the

desired

throttle

response

is

not

obtained

after

the

completion

of

the

running-in

period,

the

carburettor

should

be

re-adjusted

as

follows.

Please

refer

to

Photos

2

and

3.

Three

adjustable

controls

are

provided

on

this

carburettor.

©

The

Needle-Valve:

For

adjusting

the

mixture

strength

when

the

throttle

is

fully

open.

è

The

Mixture

Control

Screw:

For

adjusting

the

mixture

strength

at

part-throttle

and

idling

speeds,

to

obtain

steady

idling

and

smooth

acceleration

to

medium

speeds.

@

The

Throttle

Stop

Screw:

For

establishing

the

minimum

idling

speed.

(see

Photo

3)

Mixture

control

screw

Needie

valve

Photo

2

1.

Set

the

throttle

lever

1/4

open

from

the

fully

closed

position

(see

Fig.

3)

and

start

the

engine

in

the

usual

way.

It

is

preferable

to

have

the

throttle

only

slightly

open,

to

avoid

unnecessarily

high

revolutions

when

the

engine

starts.

2.

Now

open

the

throttle

fully

and

gradually

close

the

needle-valve

until

the

engine

is

running

at

its

optimum

rp.m.

in

the

air.

The

needle-valve

setting

at

this

time

will

be

1/8

to

1/4

open

from

the

maximum

r.p.m.

setting.

Note:

Make

sure

that

the

engine

ts

fully

“run-in”

before

operating

it

continuously

at

full

power.

{See

RUNNING

IN

section.)

3.

Having

set

the

needle-valve

as

described

above,

close

the

throttle

and

run

the

engine

at

idling

speed

for

approxi-

mately

5

seconds,

then

steadily

move

the

throttle

to

the

fully

open

position

by

means

of

the

throttle

servo.

(a)

If,

at

this

point,

the

engine

hesitates

before

picking

up

speed,

with

a

low-pitched

exhaust

note

and

an

excess

of

exhaust

smoke,

it is

probable

that

the

idling

mixture

is

too

rich.

In

this

case,

it

will

be

necessary

to

turn

the

mixture

control

screw

clockwise

about

45

degrees.

(b}

If,

on

the

other

hand,

the

engine

hesitates

or

even

appears

to

cease

firing

for

an

instant,

before

in-

creasing

speed,

it is

probable

that

the

idling

mixture

ts

too

lean.

In

this

case,

it

will

be

necessary

to

turn

the

mixture

control

screw

counter-clockwise

about

90

degrees

then

turn

it

clockwise

45

degrees.

Turn

the

mixture

control

screw

30

to

45

degrees

at

a

time

in

the

early

stages.

When

the

response

improves,

turn

the

mixture

control

screw

10

to

15

degrees

at

atime.

Carry

out

adjustments

progressively

and

patiently

remembering

the

symptoms

of

rich

and

lean

running,

quoted

above,

until

the

engine

responds

quickly

and

positively

to

the

throttle.

4.

The

throttle

stop

screw

is

for

fixing

the

minimum

idling

speed.

If,

after

carrying

out

mixture

adjustments,

the

idling

speed

is

found

to

be

too

high,

the

throttle

stop

screw

should

be

turned

counter-clockwise

until

the

desired

idling

speed

is

obtained.

Note:

Once

the

correct

carburettor

settings

have

been

established,

it

should

be

unnecessary

to

alter

them.

Such

slight

needle-valve

readjustments

as

may

be

required

to

compensate

for

varia-

tions

in

atmospheric

conditions,

will

not

normally

affect

the

other

two

controls.

Slight

readjustments

may

be

necessary

for

optimum

performance

if

different

types

of

fuel,

glow-

plugs

or

propellers

are

used.

In

this

case,

begin

by

flying

the

model

with

the

needle-valve

approximately

1/8

to

1/4

turn

open

from

the

peak

r.p.m.

as

a

safety

measure,

then

readjust

as

necessary.

|

REALIGNMENT

OF

MIXTURE

CONTROL

VALVE

In

the

course

of

making

carburettor

adjustments,

it

is

just

possible

that

the

Mixture

Control

Valve

may

be

tnadver-

tently

screwed

in

or

out too

far

and

thereby

moved

beyond

its

effective

adjustment

range.

Please

refer

to

Fig.

4.

Its

basic

setting

can

be

reestablished

as

follows:

First

screw

in

the

Mixture

Control

Valve,

while

looking

into

the

rotor

hole.

(See

small

sketch.)

Then,

gradually

unscrew

the

Mixture

Control

Valve

until

‘A’

is

precisely

tangential

to

the

rotor

hole

(i.e.

so

that

‘A’

and

‘B’

are

superimposed).

Finaily,

unscrew

the

Mixture

Control

Valve

a

further

180°,

as

in

the

main

sketch.

This

is

the

basic

(factory)

setting

for

the

Mixture

Control

Valve.

Mixture

control

valve

Throttle

rotor

hole

CARBURETTOR

CLEANLINESS

The

correct

functioning

of

the

carburettor

depends

on

its

small

fuel

orifices

remain-

ing

clear.

The

minute

particles

of

foreign

matter

that

are

pre-

sent

in

any

fuel

can

easily

partially

obstruct

these

orifices

and

upset

mixture

strength

so

that

engine

per-

formance

becomes

erratic

and

unreliable.

It is

recommended

that

fuel

is

passed

through

a

filter

when

the

tank

is

filled

and

that

a

good

in-line

filter

is

installed

between

the

fuel

tank

and

carburettor

and,

furthermore,

that

this

filter

is

frequently

cleaned

to

remove

dirt

and

lint

that

accumulates

on

the

filter

screen.

Finally,

ocasionally

Throttle

stop

screw

Dirt

and

fibrous

matter

mostly

accumulate

here.

x

Photo

3

remove

the

needle-valve

holder

from

the

carburettor,

using

the

wrench

supplied,

and

extract

any

remaining

foreign

matter

that

may

have

lodged

in

the

location

shown

in

Photo

3.

VALVE

CLEARANCE

ADJUSTMENT

Valve

clearances

are

correctly

set

before

any

O.S.

four-

stroke

engine

leaves

the

factory

and,

in

normal

use,

will

seldom

require

adjustment.

However,

if,

after

a

considera-

ble

amount

of

running

time

has

accumulated,

a

loss

of

power

is

detected,

or

if

the

engine

has

to

be

disassembled

or

repaired

as

a

result

of

a

crash,

valve

clearances

should

be

checked

and

readjusted

as

necessary.

For

checking

and

adjusting

the

valve

clearances,

a

valve

adjusting

kit,

contain-

ing

two

feeler

gauges

and

two

wrenches,

is

available

as

an

optional

accessory.

Note: Valve

clearances

on

this

engine

must

be

checked

and

re-set

only

WHEN

THE

ENGINE

IS

COLD.

1.

Remove

the

rocker

cover

by

unscrewing

two

Allen

screws

from

the

rocker

box

on

top

of

the

cylinder

head.

2.

Turn

propeller

until

compression

is

felt,

then

turn

it

one

quarter

turn

and

stop.

Both

valves

should

now

be

closed.

3.

The

required

valve

clearance

is

between

0.04

mm

and

0.10

mm

(.0015

to

.004

in.)

measured.

between

the

valve

stem

and

rocker-arm.

Use

the

0.04

mm

(thinner

one)

and

0.10

mm

(thicker

one)

feeler

gauges

to

check

clearance.

The

0.04

mm

feeler

should

pass

through

the

gap:

the

0.10

mm

gauge

should

not.

4.

If

the

gap

is

found

to

be

less

than

0.04

mm

or

more

than

0.10

mm,

carefully

slacken

the

locknut

on

the

rocker-

arm

with

the

5

mm

wrench

supplied,

turn

adjusting

screw

with

1.5

mm

Allen

key

to

open

or

close

gap,

then

retighten

locknut.

Finally,

re-check

gap

and

readjust

if

necessary.

IMPORTANT:

Incorrect

valve

clearances

may

cause.

difficult

starting

(due

to

valve

not

closing

property)

or

loss

of

power

(due

to

valve

not

opening

sufficiently).

NEEDLE

VALVE

EXTENSION

The

needle-valve

supplied

with

this

engine

is

designed

to

in-

corporate

an

extension

so

that,

when

the

engine

is

enclosed

within

the

fuselage,

the

needle-valve

may

be

adjusted

from

the

outside.

An

L-shaped

rod,

of

1.6

—

1.8

mm

dia.

and

appropriate

length,

should

be

inserted

into

the

needle’s

centre

hole

and

secured

by

tightening

the

set-screw

in

the

needle-valve

knob

with

the

small

Allen

key

provided.

CARE

AND

MAINTENANCE

To

ensure

that

you

obtain

long

life

and

peak

performance

from

your

engine,

observe

the

following.

1.

Avoid

running

the

engine

under

dusty

conditions.

If

necessary,

lay

a

sheet

of

plywood

or

hardboard

tn

front

and

under

the

nose

of

the

model

when

starting

the

engine.

2.

Foreign

matter

in

the

fuel

can

cause

the

carburettor

jet

to

be

partially

clogged.

Therefore:

e

rinse

out

the

fuel

tank with

methanol

or

fuel

before

installing

it

e

fit

a

fuel

filter

in

the

fuel

delivery

tube

between

tank

and

carburettor

ə

fit

a

fuel

filter

to

the

outlet

of

your

squeeze

bottle,

or

to

the

pump

inlet

if

you

use

a

manual!

or

electric

pump

e

do

not

leave

your

fuel

container

open

needlessly

e

check

filters

periodically

and

clean

them

when

necessary.

3.

Do

not

leave

raw

fuel

in

the

engine

at

the

conclusion

of

a

flying

session:

it

may

cause

corrosion.

The

best

practice

is

to

disconnect

the

delivery

tube

from

the

carburettor

while

the

engine

is

running.

Remaining

fuel

in

the

tank

should

also

be

drained

off.

IMPORTANT:

After

the

engine

has

run

dry,

liberally

inject

corrosion-inhibiting

oil

or

light

machine

oil

into

the

crankcase,

via

the

breather

hole,

until

excess

oil

runs

from

behind

the

drive

washer

when

the

engine

is

pointed

downwards.

Rotate

the

crankshaft

to

distribute

the

oil

to

the

bearings,

etc.

Failure

to

carry

out

this

procedure

may

cause

internal

rusting,

resulting

in

engine

malfunction

and

voiding

the

warranty.

4.

Clean

the

exterior

of

the

engine

with

a

clean

cotton

cloth.

If

this

is

not

done,

oil

and

dirt

will

burn

onto

the

outside

of

the

engine

each

time

it

is

run

and

the

engine

will

soon

become

blackened.

5.

If

the

engine

is

not

to

be

used

for

a

while

(more

than

two

months)

remove

the

glowplug

and

rinse

out

the

interior

with

kerosene

(not

gasoline),

by

rotating

the

crankshaft.

Shake

out

residue,

then

inject

corrosion-

inhibiting

ol

or

light

machine-oi

through

the

exhaust

pipe

and

breather

hole,

again

rotating

the

shaft

to

distri-

bute

the

protective

oil

to

all

working

parts.

6.

Avoid

unnecessary

dismantling

of

your

engine.

PARTS

LIST

Code

No.

|

Description

||

Codeno.

|

Description

44001000

|

Crankcass

[|

25960000

|

intake

Valve

Assembly

44002000

|

Crankshatt

|

45361000

|

Rocker

Arm

Assembly

44003200

Piston

|

45962000

Camshaft

45103400

Ee

a

ae

A

45564000

Cam

Follower

44004000

|

Cylinder

Head

(w/Valve

Ass'y)

||

44066000

Push

Rod

44004100

|

Cylinder

Heaa

||

44066100

Push

Rod

Cover

Assembly

45904200

|

Rocker

Cover

||

24069400

|

_

Intake

Pipe

Assembly

45605000

|

Connecting

Rod

||

24081000

|

Carburettor

Complete

44006000

|

_Piston

Pin

==

45484000

|

Choke

Valve

Assembly

44008000

|

Drive

Washer

(w/Key)

|

71615009

|

Glow

Plug

Type

“F”

29008219

|

Woodruff

Key

[|

"71905000

|

Radial

Motor

Mount

46120000

|

Thrust

Washer

||

"72200060

|

Valve

Adjusting

Kit

45910100

|

Safety

Propeller

Locknut

Assembly

||

*72108100

|

Flexible

Exhaust

Pipe

1111A

(120mm)

45913000

|

Screw

Set

||

*72108110

|

Flexible

Exhaust

Pipe

1111B

(240mm)

44014000

|

GasketSet

||

*72108120

|

Flexible

Exhaust

Pipe

1111C

(170mm)

26731002

|

Crankshaft

Bearing

(Front)

||

*72108130

|

Flexible

Exhaust

Pipe

1111D

(330mm)

45630000

|

Crankshaft

Bearing

(Rear)

|

"45910200

|

Locknut

Set

for

Spinner

45231100

|

Camshaft

Bearing

||

*45910300

|

5716-M5

Locknut

Set

The

specifications

are

subject

to

alteration

for

improvement

without

notice.

GS.

Ej

NGINE:

§

MF6.CO.,LTO.

6-15

3-chome

Imagawa

Higashisumiyoshi-ku

Osaka

546,

Japan.

TEL.

(06)

702-0225

FAX.

(06)

704-2722

*Optional

parts

©

Copyright

1988

by

O.S.

Engines

Mfg.

Co.,

Ltd.

All

rights

reserved.

Printed

in

Japan.

39306