O.S. Engines 65LA User Manual

It is of vital importance, before attempting to operate your engine, to read the general

'SAFETY INSTRUCTIONS AND WARNINGS'

section on pages 2-6 of this booklet and to strictly adhere to the advice contained therein.

●

Also, please study the entire contents of this instruction manual, so as to familiarize yourself with the controls and other features of the engine.

●

Keep these instructions in a safe place so that you may readily refer to them whenever necessary.

●

It is suggested that any instructions supplied with the aircraft, radio control equipment, etc., are accessible for checking at the same time.

CONTENTS

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE

INTRODUCTION

INSTALLATION OF THE ENGINE

NSTALLATION OF SILENCER

NEEDLE-VALVE LOCATION

BEFORE STARTING ADVICE ON SELECTION OF FUEL,

GLOW PLUG & PROPELLER

STAR TING THE ENGINE

RUNNING-IN (Breaking-in)

2~6

12~14

CARBURETTOR

CARBURETTOR AIR-BLEED ADJUSTMENT

TROUBLE SHOOTING WHEN THE

ENGINE FAILS TO START

CARE AND MAINTENANCE

OPTIONAL PARTS & ACCESSORIES

ENGINE EXPLODED VIEW & PARTS LIST

CARBURETTOR EXPLODED VIEW & PARTS LIST

THREE VIEW DRAWING

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE

Remember that your engine is not a "toy", but a highly efficient internalcombustion machine whose power is capable of harming you, or others, if it is misused. As owner, you, alone, are responsible for the safe operation of your engine, so act with discretion and care at all times. If at some future date, your O.S. engine is acquired by another person, we would respectfully request that these instructions are also passed on to its new owner.

The advice which follows is grouped under two headings according to the degree of damage or danger which might arise through misuse or neglect.

WARNINGS

These cover events which might involve serious (in extreme circumstances, even fatal) injury.

NOTES

These cover the many other possibilities, generally less obvious sources of danger, but which, under certain circumstances, may also cause damage or injury.

WARNINGS

Never touch, or allow any object to come

•

into contact with, the rotating propeller and do not crouch over the engine when it is running.

A weakened or loose propeller may

•

disintegrate or be thrown off and, since propeller tip speeds with powerful engines may exceed 600 feet(180 metres) per second, it will be understood that such a failure could result in serious injury, (see 'NOTES' section relating to propeller safety).

Model engine fuel is poisonous. Do not

•

allow it to come into contact with the eyes or mouth. Always store it in a clearly marked container and out of the reach of children.

Model engine fuel is also highly

•

flammable. Keep it away from open flame, excessive heat, sources of sparks, or anything else which might ignite it. Do not smoke or allow anyone else to smoke, near to it.

•

Never operate your engine in an enclosed space. Model engines, like automobile engines, exhaust deadly carbonmonoxide. Run your engine only in an open area.

Model engines generate considerable

•

heat. Do not touch any part of your engine until it has cooled. Contact with the muffler (silencer), cylinder head or exhaust header pipe, in particular, may result in a serious burn.

NOTES

This engine was designed for model

•

aircraft. Do not attempt to use it for any other purpose.

Mount the engine in your model securely,

•

following the manufacturers' recommendations, using appropriate screws and locknuts.

Be sure to use the silencer (muffler)

•

supplied with the engine. Frequent exposure to an open exhaust may eventually impair your hearing. Such noise is also likely to cause annoyance to others over a wide area.

If you remove the glowplug from the engine

•

and check its condition by connecting the battery leads to it, do not hold the plug with bare fingers.Use an appropriate tool or a folded piece of cloth.

Fit a top-quality propeller of the diameter

•

and pitch specified for the engine and aircraft. Locate the propeller on the shaft so that the curved face of the blades faces forward-i.e. in the direction of flight. Firmly tighten the propeller nut, using the correct size wrench.

NOTES

Always check the tightness of the propeller

•

nut and retighten it, if necessary, before restarting the engine, particularly in the case of four-stroke-cycle engines. If a safety locknut assembly is provided with your engine, always use it. This will prevent the propeller from flying off in the event of a "backfire", even if it loosens.

If you fit a spinner, make sure that it is a

•

precision made product and that the slots for the propeller blades do not cut into the blade roots and weaken them.

Preferably, use an electric starter. The

•

wearing of safety glasses is also strongly recommended.

Discard any propeller which has become

•

split, cracked, nicked or otherwise rendered unsafe. Never attempt to repair such a propeller: destroy it. Do not modify a propeller in any way, unless you are highly experienced in tuning propellers for specialized competition work such as pylon-racing.

Take care that the glow plug clip or battery

•

leads do not come into contact with the propeller. Also check the linkage to the throttle arm. A disconnected linkage could also foul the propeller.

After starting the engine, carry out any

•

needle-valve readjustments from a safe position behind the rotating propeller. Stop the engine before attempting to make other adjustments to the carburettor.

NOTES

Adjust the throttle linkage so that the engine

•

stops when the throttle stick and trim lever on the transmitter are fully retarded. Alternatively, the engine may be stopped by cutting off the fuel supply. Never try to stop the engine physically.

Take care that loose clothing (ties, shirt

•

sleeves, scarves, etc.)do not come into contact with the propeller.Do not carry loose objects (such as pencils, screwdrivers, etc.) in a shirt pocket from where they could fall through the propeller arc.

Do not start your engine in an area

•

containing loose gravel or sand. The propeller may throw such material in your face and eyes and cause injury.

For their safety, keep all onlookers

•

(especially small children) well back (at least 20 feet or 6 meters) when preparing your model for flight. If you have to carry the model to the take-off point with the engine running, be especially cautious. Keep the propeller pointed away from you and walk well clear of spectators.

Warning! Immediately after a glowplug-

•

ignition engine has been run and is still warm, conditions sometimes exist whereby it is just possible for the engine to abruptly restart if the propeller is casually flipped over compression WITHOUT the glowplug battery being reconnected. Remember this if you wish to avoid the risk of a painfully rapped knuckle!

INTRODUCTION

THE MAX-40LA, 46LA and 65LA have been developed to meet the requirements of beginners and sport flyers. Of modern design and having a separate needle-valve unit mounted at the rear, where manual adjustment is safely remote from the rotating propeller, they offer the advantages of reliability and easy handling, at lower cost. Like all O.S. engines they are built to standards of engineering excellence that have evolved through more than 60 years' experience in the design and production of model internal-combustion engines. Advanced modern precision machinery, top quality materials and the efforts of highly skilled craftsmen and technicians are combined to ensure a continuation of the levels of performance, durability and reliability for which O.S. is world famous. The MAX-46LA has a larger cylinder diameter , but both the 40LA and 46LA engines have the same external dimensions.

The 'midnight blue' external finish may be decolorized by very high surface temperature or by certain solvents. Such decolorization does not affect engine perfor-mance, however.

Cylinder head

Carburettor

Propeller nut

Crankshaft

Fuel inlet

Drive Hub

Propeller washer

Glowplug

Needle valve

Fuel outlet

Cover Plate

Silicone Tube

Crankcase

Connect the short length of fuel tubing supplied securely between the fuel outlet and the fuel inlet. In the event of the tube becoming damaged, it should be replaced with a suitable length of best quality 5mm ODX2mm ID silicone tubing. Use similar material to connect the fuel inlet nipple to the fuel tank.

INSTALLATION

Installation in the model

A typical method of beam mounting is shown below,left.

At least 12mm(1/2")

At least 12mm(1/2")40-46LA 15mm(5/8")65LA

Make sure that the mounting beams are parallel and that their top surfaces are in the same plane.

CORRECT

O.S. radial motor mount (Available as an optional extra part. See parts list)

Rigid hardwood (e.g. maple)

INCORRECT

How to fasten the mounting screws.

3mm steel nuts (40-46LA) 4mm(65LA)

Spring washer or lock washer

Tighten second nut firmly down onto first nut.

Tighten this nut first.

Steel washer

3.5mm steel screw (40-46LA) 4mm(65LA)

Hardwood mounting beams

3mm steel Allen screw

Spring washer

Hardwood such as cherry or maple.

Front view

Side view

Top surfaces are in the same plane.

Top surfaces are not in the same plane.

Re-align the surfaces as necessary

Opposite beam

Top surfaces are not in the same plane.

Engine does not seat firmly.

O.S. radial motor mount (cast aluminum)

NEEDLE-VALVE EXTENSION

The needle-valve supplied with these engines is designed to incorporate an extension so that, when the engine is enclosed within the fuselage, the needle-valve may be adjusted from the outside. Cut a commercially available rod to the required length, bend one end to an L shape, insert it into needle's center hole and secure it by tightening the set-screw in the needle-valve knob with 1.5mm. Allen key.

INSTALLATION OF SILENCER

The angled exhaust of the silencer can be rotated to any desired position in the following manner:

1) Loosen the locknut and assembly screw.

2) Set the exhaust outlet at the required position by rotating the rear part of the silencer.

3) Re-tighten the assembly screw, followed by the locknut. The standard silencer is quite effective but reduces power to some degree.

Assembly screw

Exhaust pressure nipple

Reminder!

Model engines generate considerable heat. Do not touch any part of your engine until it has cooled. Contact with the muffler (silencer), cylinder head or exhaust header pipe, in particular, may result in a serious burn.

Cone baffle

Turn to requlred position

Exhaust outlet

NEEDLE-VALVE LOCATION

As delivered from the factory, the MAX-40LA, 46LA & 65LA have the needle-valve assembly installed vertically. However, if more convenient for a particular installation, the needle-valve may be reinstalled horizontally. The procedure for relocating the needle-valve is as follows:

Locknut

Remove the two cover-plate screws which secure

1. the needle-valve assembly bracket, then carefully remove the two screws by which the needle-valve unit is attached to the bracket.

Rotate the needle-valve unit through 90˚ and reattach it to the bracket in the required position (see sketch right).

Note: As self-tapping screws are used for unit attachment, screw them in carefully so that screw threads match those of the unit body precisely.

Finally, secure the complete assembly to rear cover plate as before.

Needle Valve unit

Cover plate fitting holes

Needle-Valve Assembly Bracket

Needle Valve unit attachment screws

Vertical position (Factory position)

Horizontal position

BEFORE STARTING

Tools, accessories, etc.

The following items are necessary for operating the engine.

1 Fuel

Model glowplug engine fuel of good quality, preferably containing a small percentage of nitromethane. (See "Advice on selection of fuel, glowplug and propeller")

2 Glowplug

O.S. A3 glowplug is installed in the engine.

3 Propeller

Suggested size is 11X5 (40LA), 11X6 (46LA), or 12X6 (65LA).

4 Glowplug battery

The power source for heating the glowplug may be either a large heavy-duty 1.5volt dry cell, or preferably, a 2-volt rechargeable lead-acid cell (accumulator).

If a 2-volt cell is employed, use a resistance wire, as shown, to reduce applied voltage, otherwise the element

1.5 volt heavy-duty dry battery

will overheat and burn out.

or 2 volt rechargeable lead-acid cell (at least 5Ah)

Warning (Very hot)

Never touch the nichrome wire while the battery is connected.

Resistance coil (nichrome wire)

Battery leads

Adjust applied voltage by changing the position of clip on resistance coil until glowplug element is glowing bright red.

Raise

voltage to

increase

brightness.

Lower voltage to

reduce brightness.

5 Plug wrench

Used for tightening glowplug. The O.S. long plug wrench is available as an optional accessory.

6 Battery leads

These are used to conduct current from the battery to the glowplug. Basically, two leads, with clips, are required, but, for greater convenience, twin leads with special glowplug connectors, as shown on the right, are commercially available.

7 Fuel tank

For installation in the model, a 200cc(7oz.) for 40.46LA, or a 350cc(12oz.) for 65LA, is suggested.

8 Fuel bottle or pump

For filling the fuel tank, a simple, polyethylene "squeeze" bottle, with a suitable spout,is all that is required. Alternatively, one of the purpose-made manual or electric fuel pumps may be used to transfer fuel directly from your fuel container to the fuel tank.

9 Fuel can filter

Fit a filter to the outlet tube of your refuelling container to prevent entry of foreign matter into the fuel tank. (Refer to of STARTING

THE ENGINE section.)

Fuel bulb

Battery leads

Fuel pumps

Electric

Fuel Can Filter

12V Battery

For tightening glowplug

Manual

Starter

10 Silicone tubing

This is required for the connection between the fuel tank and engine.

11 Electric starter and starter battery

An electric starter is recommended for starting.

Fuel and pressure lines

Connect suitable lengths of silicone tubing, as illustrated, after installing the engine.

Fuel lines and position of fuel tank

Locate the fuel tank so that the top of the tank is 510mm (1/4-3/8") above the level of the needle-valve.

Note: When cutting silicone tubing......

Use knife or razor blade.

*If you should need to clean out silicone tubes, use methanol

or glow-fuel, not gasoline.

Pay attention to tank height

Silicone tubing

Fuel level

6~8

Do not use wire cutters or pliers

Silencer (muffler) pressurized fuel system

To reduce variation in fuel "head" and ensure steady fuel delivery at the carburettor, it is advisable to employ a silencer (muffler) pressurized fuel system, i.e. to use the silencer outlet nipple to pressurize the fuel tank as shown at left.

ADVICE ON SELECTION OF FUEL, GLOWPLUG & PROPELLER

Fuel

Use a good quality commercial fuel or one of the blends shown in the table. Fuel "A" is suitable for running-in and ordinary use. Fuel "B" is for use when more power is required and for improved flexibility. Note that even a small quantity of nitromethane (3-5%) will improve flexibility, making the needle-valve adjustment less critical and improving throttle response. Use only materials of the highest purity. Synthetic oils are permissible but are less tolerant of a "lean run" than castor-oil. If, therefore, a synthetic lubricant is used in the fuel, readjust the needle-valve to a slightly richer setting, as a safety measure, in case the fuel/air mixture becomes too lean through maneuvers in flight. If a more powerful fuel is used, the engine should be checked out to make sure that it is sufficiently run-in to operate on that particular fuel without overheating. Do not use fuels containing less than 18% lubricant.

Methanol Castor Oil Nitromethane

Reminder!

Model engine fuel is poisonous. Do not allow it to come into contact with the eyes or mouth. Always store it in a clearly marked container and out of the reach of children.

Model engine fuel is also highly flammable. Keep it away from open flame, excessive heat, sources of sparks, or anything else which might ignite it. Do not smoke, or allow anyone else to smoke, near to it.

PROPELLER

Suggested propeller sizes are given in the table. As the ideal propeller diameter, pitch and blade area vary according to the size, weight and type of model, final propeller selection will require in flight experimentation.

75% 20%

65% 20% 15%

Reminder!

Never touch, or allow any object to come into contact with, the rotating propeller and do not crouch over the engine when it is running.

LA Series

40LA 46LA 65LA

GLOWPLUG

An O.S. A3 glowplug is installed in the engine. Other recommended O.S. plugs are Nos.8 and A5. Carefully fit plug finger-tight, before final tightening with the correct size plug wrench.

Running-in

11✕5

✕6

Trainer & Sport

10✕6~7,10.5✕6,11✕5~6

11✕6~7

✕7

8,13✕6~8

The role of the glowplug

With a glowplug engine, ignition is initiated by the application of a 1.5-volt power source. When the battery is disconnected, the heat retained within the combustion chamber remains sufficient to keep the plug filament glowing, thereby continuing to keep the engine running. Ignition timing is 'automatic' : under reduced load, allowing higher rpm, the plug becomes hotter and, appropriately, fires the fuel/air charge earlier; conversely, at reduced rpm, the plug become cooler and ignition is retarded.

Glowplug life

Particularly in the case of very high performance engines, glowplugs must be regarded as expendable items. However, plug life can be extended and engine performance maintained by careful use, i.e.:

Install a plug suitable for the engine.

•

Use fuel containing a moderate percentage of

•

nitromethane unless more is essential for racing events.

Do not run the engine too lean and do not leave the

•

battery connected while adjusting the needle.

When to replace the glowplug

Apart from when actually burned out, a plug may need to be replaced because it no longer delivers its best performance, such as when:

Filament surface has roughened and turned white.

•

Filament coil has become distorted.

•

Foreign matter has adhered to filament or plug

•

body has corroded. Engine tends to cut out when idling.

•

Starting qualities deteriorate.

•

STARTING THE ENGINE

Preparations

1 Installing the glowplug

Install the washer on the glowplug and screw carefully into cylinder-head, making sure that it is not cross-threaded before tightening firmly.

2 Installing the propeller

First, mount the propeller on the engine by tightening the prop nut or spinner-nut lightly, and make sure of the position where compression is felt, turning the propeller counter-clockwise slowly. Then tighten firmly as explained below.

For accurately centering the starter's rubber drive insert, use an O.S. solid alloy spinner-nut. (Available as an optional extra part).

Alternatively, a spinner assembly, enclosing the propeller boss, may be used, but make sure that it is of sturdy construction and that the spinner shell does not loosen when the starter is used.

Wrench

Glow plug

Washer

Warning: When using a spinner assembly, make sure that the notches in the spinner shell are large enough to clear the propeller blades and so do not cut into and weaken the blade roots.

Tighten the spinner nut firmly so that compression is first felt as indicated (i.e. with blades horizontal) when turning the propeller in the direction of arrow.

4 Filling the fuel tank

Do not allow fuel to overflow into silencer when refuelling, otherwise engine may become flooded and difficult to start.

3 Checking for compression leakage

Check compression leakage by turning the propeller up to this position after compression is felt.

If leakage is detected, remove the glowplug, carefully wipe threads, re-insert and tighten firmly.

Dribble a few drops of fuel around the glowplug and look for air bubbles.

Compression is first felt around this posit

ion when turning

the propeller slowly.

Re-connect delivery tube to engine after tank is filled.

Fuel pump

Use a fuel can filter (e.g. O.S. Super Filter).

Disconnect delivery tube from the fuel inlet, and connect it to the tubing from the fuel pump.

Do not let dirt or dust enter fuel can.

Fuel (model glow-plug engine fuel)

5 Opening and closing of the needle-valve

Open

Turn needle-valve clockwise to close (for leaner mixture). Turn needle-valve counter-clockwise to open (for richer mixture).

6 Setting the needle-valve

Open the needle-valve 1 turns (for 40,46LA) and 2 turns (for 65LA) in the direction of arrow from the closed position.

7 Open the throttle fully

Fully closed position

Fully opened position Throttle

8 Priming

Open

Fuel Tube

Needle-valve

The position where the needle-valve stops is the fully closed position. It may be convenient to remember the position of the mark or set-screw at this time.

Place your finger over the carburettor to choke intake.

Turn the propeller two revolutions while watching the fuel line.

Fuel inlet

Fuel will flow from tank to carburettor as propeller is turned.

Priming quantity

After fuel has been drawn to the carburettor, flip the propeller two more revolutions, with intake choked, to draw fuel into engine. Above procedure is called priming.

NOTE (IMPORTANT) The quantity of fuel drawn into the engine by priming is an important factor in starting the engine successfully.

When the engine is being started for the first time, turn the propeller two revolutions after fuel reaches the fuel inlet, as described above. However, when restarting the engine immediately after a run, one revolution, or even no priming at all may be required. The engine's requirements will be quickly learned with experience.

Do not energize the glowplug at this stage.

Turn the propeller 3 to 4 turns counter-clockwise smartly by finger in the direction of arrow. Turn approx. 10 turns instead when the engine is cold.

Hold model securely when starting

Glowplug battery. Place as far to the rear as possible.

Starter

Be careful not to be hit by propeller!

Setting the throttle

Assistant should hold the model so that it cannot move forward when the engine starts.

Assistant

Heat glowplug

Connect battery leads as shown (polarity is immaterial.)

Apply electric starter

Starting battery

Fully closed position

Set at this Position.

Fully opened position

Check that the throttle is one-third open from the fully closed position. Bring the starter into contact with the spinner nut or spinner and depress the starter switch for one or two seconds. Repeat if necessary. When the engine fires, withdraw the starter immediately.

Attention: Never place your finger over the carburettor intake when applying the starter. Such an action will cause an excess quantity of fuel to be drawn into the cylinder and result in hydraulic lock that may damage the engine.

Engine starts

If the engine does not start, refer to the TROUBLE SHOOTING CHART on page 26-27.

BEWARE of the rotating propeller.

Needle-valve adjustment(1)

Slowly advance throttle to its fully open position, then gradually close the needle-valve until the exhaust sound changes from an irregular pitch (four-cycle) to a steady pitch (two-cycle).

Listen to the sound carefully.

In the interests of safety, keep your face and other parts of the body away from the vicinity of the propeller.

Close the needlevalve gradually until the engine sound is changing from a four-cycle into a two-cycle in pitch.

Disconnect battery leads

Disconnect the battery leads from the engine with care so that the plug clip does not touch the rotating pro-peller.

If the engine stops when battery leads are disconnected, close the needle-valve a little (approx. 30˚) further, and restart the engine.

Needle-valve adjustment(2)

As the needle-valve is closed beyond the initial readjustment, the r.p.m. of the engine will be increased and a continuous high-pitched exhaust note, only, will be heard.

Key to the needle-valve adjustment. (Turn 10-15˚ at a time.)

Turn the needle-valve 10-15˚ in the direction of arrow, and wait momentarily for the change of r.p.m. After the r.p.m. of the engine increases, turn the needle-valve another 10-15˚ and wait for the next change of r.p.m.

As the speed of the engine does not instantly change with needle-valve readjustment, small movements, with pauses between, are necessary to arrive at the optimum setting.

IMPORTANT NOTE

When fine-tuning the needle-valve to reach peak performance, take care not to run the engine too lean and cause it to overheat. Be sure to observe the simple running-in procedures described on Page 22.

Needle-valve adjustment(Summary)

Practical best(optimum) needle-valve setting

Clear, high-pitched two-stroke exhaust note

Maximum rpm setting("Lean").

20~30˚

Intermittent, high-pitched two-stroke note superimposed on low "four-stroke" sound.

Disconnect battery leads from glowplug at about this point.

Exhaust note starts to change.

Note: Although this is a two-stroke engine it fires like a four-stroke at these rich needle-valve settings-i.e. ignition of the fuel charge takes place at every fourth stroke of the piston instead of at every second stroke.

NOTE: The above sketch is for reference purposes only.

Actual needle positions may differ from those shown.

The engine may stop if the battery leads are disconnected from the glowplug while the engine is running rich.

"Rich" needle-valve setting when starting the engine.

On starting from cold, with the needle-valve set at the rich starting position:

a good deal of white smoke is emitted, accompanied by a relatively low-pitched "four-stroke" exhaust note.

As the needle-valve is closed and the r.p.m. increases:

an intermittent high-pitched two-stroke note will be superimposed on the low-pitched "four-stroke" note. Exhaust smoke will be less dense and grey in colour.

Further needle-valve closure:

exhaust note is now a steady high-pitched sound,rising higher in pitch as needle-valve is closed and The grey smoke will be lighter. (However, make sure that engine is fully run in.)

Finally:

maximum rpm is reached and will fall off (or engine will stop) if needle -valve is closed any further. Exhaust gas will be very light.

Now, re-open needle-valve 20-30˚

This will produce the practical best (i.e. optimum) rpm setting (lower than maximum rpm). A light grey exhaust emission may be observed.

Take note of this position of the needle-valve.

increase.

Subsequent starting procedure

Once the optimum needle-valve setting has been established (see "Needle-valve adjustmentSummary") the procedure for starting is simplified as follows:

1) Open the needle-valve one half-turn (180˚) from

the optimum setting.

2) Open the throttle fully, place your finger over the

carburettor intake and rotate the propeller through two revolutions to prime the engine.

3) Set the throttle one-third open from the fully closed

position, energize the glowplug and apply the starter. When the engine starts, re-open the throttle and re-adjust the needle-valve to the optimum setting.

Note: When re-starting the engine on the same day, provided that atmospheric conditions have not changed significantly, it may be practicable to re-start the engine on its optimum (running) setting. Also, if the engine is being re-started immediately after a run (i.e.hot), priming should not be necessary.

How to stop the engine

Close the throttle to reduce to the lowest possible r.p.m.

With the transmitter throttle trim lever fully retarded, adjust the throttle servo linkage so that the throttle rotor is fully closed (i.e.engine stopped) when the stick is fully retarded.

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 stresses. However, because 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.The process is as follows:

1) Start the engine and, with the throttle fully open, open the needle-valve an extra half turn (180˚) from the optimum setting. This will produce a rich mixture that will result in cooler running. Allow the engine to run out a full tank on the ground. (Avoid dusty surroundings.)

2) Now fly the model with the needle-valve re-set 2030 degrees open from the optimum setting ( i.e. 40-60˚ from the highest rpm setting).

3) Close the needle-valve very slightly on successive flights so that the engine is running on its optimum needle setting at the fifth or sixth flight.

CARBURETTOR

These engines are equipped with a throttle type carburettor which provides a wide range of engine speed control. With the throttle lever linked to a suitable servo in the model, movement of the throttle control on the transmitter will enable engine r.p.m. to be varied, proportionally, from idling speed to full power. The carburettor of your engine has been factory set for the approximate best results and no adjustment (except to the needle-valve) should be required provided that the fuel tank is correctly located, as previously described. After the engine has been runin, check the operation of the throttle according to the following chart. Re-adjust the controls only when necessary.

Re-set the idling position at a little higher r.p.m.

Start the engine.

Make sure that the throttle is fully open.

Adjust the neede-valve.

Close the throttle gradually.

Find the idling position.

Fix the idling position.

Open the throttle fully.

20-30

open from maximum

r.p.m. setting.

The position where the lowest possible r.p.m. ,with steady running, is obtained.

Set the throttle opening by means of the throttle trim on the transmitter so that the lowest practical speed, without risk of the engine stopping,is obtained.

Refer to the CARBURETTOR AIR-BLEED ADJUSTMENT section on page 25.

Engine stops.

Does the engine regain full power?

Continue running at high speed for 10 seconds.

Close the throttle.

Run at idling speed for 5 seconds.

Does the engine stop?

Apply full throttle.

Does the engine regain full power immediately?

Yes.

No.

Yes.

CARBURETTOR AIR-BLEED ADJUSTMENT

Pre-Flight Check

Start engine and adjust needlevalve as previously described.

Close the throttle gradually.

Find the idling position.

approx.

Repeat the procedure while opening and closing

the throttle until the best result is obtained.

Hold the model.

Hold model level, then slowly raise its nose.

If revolutions increase.

15˚

If engine runs unevenly or stops.

Stop the engine.

Note: Stop engine by pinching fuel delivery tube. Do not touch needle-valve.

These adjustments can be made without stopping the engine. However, it is advisable for beginners to stop the engine for safety reasons.

Open air-bleed screw.

Half turn at a time.

Immediately point nose down, so that engine runs steadily again.

Stop the engine.

Attention: Do not leave the glowplug connected to the battery

while adjusting the carburettor throttle.

approx. 15˚

Close air-bleed screw.

Half turn at a time.

TROUBLE SHOOTING WHEN THE ENGINE FAILS TO START

Four key points

For quick, reliable starting, the following four conditions are required.

1 Good compression. 2 Adequate "glow" at glowplug. 3 Correct mixture. 4 Sufficient electric starter rotating speed.

If the engine fails to start, or does not keep running after being started, check symptoms against the following chart and take necessary corrective action. Note: The most common causes of trouble are marked with three asterisks, the less common problems with one or two asterisks.

Symptom

Engine fails to fire.

Factor

Cause

Sluggish rotation

Glowplug battery discharged.

Glowplug element is burned out

Something wrong with battery leads. Engine "flooded" due to excessive priming.

Insufficient priming.

......

.....

....

.....

Corrective action

Recharge the electric starter battery.

Recharge lead-acid cell or replace dry battery. (Note: An unused, or almost unused, dry battery may sometimes be of insufficient capacity if it is "old stock".) Replace glowplug. Check that applied voltage is not too high.

Check glowplug heating using other leads. Close needle-valve fully and remove glowplug, then flip propeller to pump

out excess fuel. (Invert engine, if possible, while pumping out excess). Re-start engine. (Priming is not necessary at this time.)

Repeat priming procedure referring to 8 Priming.

Symptom

Engine fires intermittently but does not run.

Engine fires once or twice, then fails to fire.

Engine starts but revolutions decrease and engine eventually stops.

Engine starts, then revolutions increase and engine cuts out.

Engine stops when battery leads are disconnected after starting.

Factor

2 3

3 3

3 2

Cause

Incorrect heating of glowplug.

Over priming.

Sluggish rotation.

Glowplug battery discharged.

Insufficient priming.

Mixture too rich.

Fuel not reaching the engine.

Mixture too rich.

Mismatch of glow plug and fuel.

.....

........

......

.....

.......

.....

.......

Corrective action

Voltage too high or too low. Re-check and readjust referring to "BEFORE STARTING" paragraph 4.

Continue flipping propeller. If engine does not start after more than 10 flips, disconnect battery from glowplug and leave for a few minutes, then reenergize plug and flip prop again. If engine still does not start, remove glowplug and pump out excess fuel by flipping prop quickly.

Then re-start. (Priming is not necessary.) Recharge the electric starter battery.

Recharge lead-acid cell or replace dry battery. (Note: An unused, or almost unused, dry battery may sometimes be of insufficient capacity if it is "old stock".)

Repeat priming procedure referring to 8 Priming.

Close needle-valve half turn (180˚) and wait for several minutes then restart.(Priming is not necessary.)

Make sure that tank is filled with fuel. Check that there is not something wrong with fuel tubing (kinked or split). Check that carburettor is not clogged with dirt.

Close the needle-valve a little.

....

Change fuel or glowplug.

CARE AND MAINTENANCE

To ensure that you obtain long life and peak performance from your engine, observe the following.

Avoid running the engine under dusty conditions.

1. If necessary, lay a sheet of plywood or hard-board in front and under the nose of the model when starting the engine.

Foreign matter in the fuel can cause the

2. carburettor jet to be partially clogged.

Therefore:

rinse out the fuel tank with methanol or fuel before

• installing it.

fit a fuel filter to the fuel delivery tube between tank

• and carburettor.

fit a fuel filter to the outlet of your squeeze bottle,

• or to the pump inlet if you use a manual or electric

pump. do not leave your fuel container open needlessly.

• check filters periodically and clean them when

• necessary.

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.

Clean the exterior of the engine with a clean cotton

4. 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.

If the engine is not in use for a while (more than

5. two months) remove the glowplug and rinse out the interior with kerosene (not gasoline), by rotating the crankshaft. Shake out residue, then inject light machine-oil through the plug hole and carburettor intake, again rotating the shaft to distribute the protective oil to all working parts. Gasoline, thinner, kerosene and light machine oil cause swelling and deterioration of plastic parts, "O" rings and fuel tubing. Use methanol for cleaning these parts.

Avoid unnecessary dismantling of your engine.

O.S. GENUINE PARTS & ACCESSORIES

RADIAL MOTOR MOUNT

■

(71906200) for 40,46LA (71905200) for 65LA

SUPER SILENCER

■

E-3030S E-4010S

(23325030) for 40,46LA (26028010) for 65LA

SILENCER EXTENSION

■

ADAPTORS

(23325100) for 40,46LA (26625340) for 65LA

LONG PROPELLER NUT SET

■

(73101000) for 40~46LA (73101010) for 65LA

BUBBLESS WEIGHT

■

(Bubble Eliminating Tank Weight) (71531000)

GLOW PLUG

■

(71605300)

SPINNER NUT

■

LONG SOCKET WRENCH

■

WITH PLUG GRIP

(71521000)

SUPER FILTER (L

■

(72403050)

(23024009) for 40,46LA

"-28(L)

(45024000) for 65LA

"-24

)

EXPLODED VIEW

N.+M3X12

(

MAX-40LA

)

N.+M3.5X5

✽

Type of screw C…Cap Screw M…Oval Fillister-Head Screw

-1

-2

F…Flat Head Screw N…Round Head Screw S…Set Screw

N.+M3X8

S.3X3

-5

-6

-4

-3

-2

-1

ENGINE PARTS LIST

Description

Cylinder Head

Cylinder & Piston Assembly

Piston Pin

Connecting Rod

Carburettor Complete (40D)

Carburettor Gasket

-1

Carburettor Retaining Screw

-2

Propeller Nut

Propeller Washer

Drive Hub

Thrust Washer

Crankcase

Gasket Set

Crankshaft

Cover Plate

Needle Valve Assembly

Needle

-1

"O" Ring(2pcs.)

-2

Set Screw

-3

Ratchet Spring

-4

Needle Valve Body

-5

Needle Valve Body Retaining Screw

-6

Needle Valve Assembly Bracket

Screw Set E-3030 Silencer Exhaust Pressure Nipple Assembly Screw Retaining

Specifications are subject to alteration for improvement without notice.

Screw

(2pcs.)

(MAX-40LA)

Midnight Blue

Code No.

2 4004 000 2 4004 010

2 4003 010 2 3356 000 2 4005 000 2 4081 000 2 2615 000 2 3081 706 2 3210 007 2 4009 000 2 4008 000 2 2020 001

2 4001 001 2 4001 011

2 3364 000 2 3302 000 2 4007 110 2 6582 900 2 4081 970 2 4981 837 2 6381 501 2 6711 305 2 6582 910 2 6582 920 2 4007 120 2 4013 000 2 3325 020 2 2681 957 2 3325 320 2 2625 404

Natural

EXPLODED VIEW

N.+M3X12

(

MAX-46LA

)

N.+M3.5X5

✽

Type of screw C…Cap Screw M…Oval Fillister-Head Screw

-1

-2

F…Flat Head Screw N…Round Head Screw S…Set Screw

N.+M3X8

S.3X3

-5

-6

-4

-3

-2

-1

ENGINE PARTS LIST

(MAX-46LA)

Description

Cylinder Head

Cylinder & Piston Assembly

Piston Pin

Connecting Rod

Carburettor Complete (40D)

Carburettor Gasket

-1

Carburettor Retaining Screw

-2

Propeller Nut

Propeller Washer

Drive Hub

Thrust Washer

Crankcase

Gasket Set

Crankshaft

Cover Plate

Needle Valve Assembly

Needle

-1

"O" Ring(2pcs.)

-2

Set Screw

-3

Ratchet Spring

-4

Needle Valve Body

-5

Needle Valve Body Retaining Screw

-6

Needle Valve Assembly Bracket

Screw Set E-3030 Silencer Exhaust Pressure Nipple Assembly Screw Retaining

Specifications are subject to alteration for improvement without notice.

Screw

(2pcs.)

Code No.

2 4004 100 2 4003 100 4 5806 000 2 4005 000 2 4081 000 2 2615 000 2 3081 706 2 3210 007 2 4009 000 2 4008 000 2 2020 001 2 4001 100 2 4014 100 2 3302 000 2 4007 110 2 6582 900 2 4081 970 2 4981 837 2 6381 501 2 6711 305 2 6582 910 2 6582 920 2 4007 120 2 4013 000 2 3325 020 2 2681 957 2 3325 320 2 2625 404

EXPLODED VIEW

N.+M3X18

-1

(

MAX-65LA

)

-1

-2

N.+M3.5X6

✽

Type of screw C…Cap Screw M…Oval Fillister-Head Screw

F…Flat Head Screw N…Round Head Screw S…Set Screw

S.3X3

-3

N.+M3X12

-1

-2

-4

-5

-6

ENGINE PARTS LIST

(MAX-65LA)

Code No.

2 6504 000

Specifications are subject to alteration for improvement without notice.

2 6021 110

-1 2 6503 000

4 5606 000

2 6025 000

2 6581 000

4 6215 000

-1 2 5081 700

-2 4 5010 002

2 8009 002

2 6508 000

2 6022 200

2 6501 000

2 6022 000

2 6507 000

2 6582 930

2 6582 900

2 4081 970

-1 2 4981 837

-2 2 6381 501

-3 2 6711 305

-4 2 6582 910

-5 2 6582 920

-6 2 6513 000

7 1605 300 2 6028 000 2 2681 953 2 6028 100 2 6625 210

Cylinder Head

Head Gasket

Cylinder & Piston Assembly Piston Pin Connecting Rod Carburettor Complete(60J) Carburettor Gasket Carburettor Retauning Screw(2pcs.) Propeller Nut Propeller Washer Drive Hub Thrust Washer Crankcase Crankshaft

Cover Plate

Needle Valve Assembly Bracket Needle Valve Assembly

Needle Valve Body

Screw Set Glow Plug A3 Silencer(E-4010)

Description

Needle

"O"Ring(2pcs.) Set Screw

Ratchet Spring

Needle Valve Body Retaining Screw

Exhaust Pressure Nipple Assembly Screw Retaining Screw(2pcs.)

CARBURETTOR EXPLODED VIEW & PARTS LIST

TYPE 40D

N.+M3X6

- 1

✽

Type of screw

C…Cap Screw M…Oval Fillister-Head Screw

F…Flat Head Screw N…Round Head Screw S…Set Screw

Code No.

2 2081 408

-1

2 2081 313

2 4081 200

2 4081 600

2 4081 100

2 4081 300

2 2615 000

2 3081 706

N.+M2.6X15

N.+M3.5X5

Description Throttle Lever Assembly Throttle Lever Retaining Screw Carburettor Rotor Airbleed Screw Carburettor Body Throttle Stop Screw Carburettor Gasket Carburettor Retaining Screw

N.+M2.6X6

2 3 4 5 6 7 8

Specifications are subject to alteration for improvement without notice.

N.+M3X6

-1

C.M2.6X18

Code No.

2 2081 408 2 2081 313 2 6581 200 2 6029 500 2 6581 100 2 2826 131 2 6029 430 4 6215 000 2 5081 700

TYPE 60J

Description

Throttle Lever Assembly

Throttle Lever Retaining Screw Carburettor Rotor Air-bleed Screw

Carburettor Body Throttle Stop Screw Nozzle For Remote Needle Valve Carburettor Rubber Gasket Carburettor Retaining Screw

N.+M3.5X6

MAX-40LA/46LA THREE VIEW DRAWING

40LA SPECIFICATIONS

Displacement

■

Bore

■

Stroke

■

Practical R.P.M.

■

Power output

■

Weight

■

6.49 cc (0.396cu.in.

21.2 mm (0.835in.

18.4 mm (0.724in.

2,000

1.0 bhp / 15,000 r.p.m. 269g (9.5oz.

46LA SPECIFICATIONS

Displacement

■

Bore

■

Stroke

■

Practical R.P.M.

■

Power output

■

Weight

■

7.64 cc (0.467cu.in.

23.0 mm (0.906in.

18.4 mm (0.724in.

2,000

1.2 bhp / 15,000 r.p.m. 272g (9.6oz.

16,000 r.p.m.

)

16,000 r.p.m.

)

Dimensions(mm)

) ) )

MAX-65LA THREE VIEW DRAWING

Dimensions(mm)

65LA SPECIFICATIONS

Displacement

■

Bore

■

Stroke

■

Practical R.P.M.

■

Power output

■

Weight

■

10.85 cc (0.662cu.in.

24.0 mm (0.945 in.

16,000 r.p.m.

2,000

1.7 bhp / 16,000 r.p.m. 535 g (18.87 oz.

) ) )

)

UNF5/16-24

35.6

85.4 107

43.8

42 62

91.2

6-15 3-Chome Imagawa Higashisumiyoshi-ku Osaka 546-0003, Japan

TEL. (06) 6702-0225

FAX. (06) 6704-2722

URL : http://www.os-engines.co.jp

110102

O.S. Engines 65LA User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual