O.S. Engines 32SX-HX User Manual

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

'SAFETY INSTRUCTIONS AND WARNINGS'

section on pages 2-5 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 model, radio control equipment, etc., are accessible for checking at the same time.

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE

CONTENTS

2~5

SUBSEQUENT READJUSTMENTS

INTRODUCTION

BASIC ENGINE PARTS, INSTALLATION

NOTES CONCERNING THE RECOIL STARTER

BEFORE STARTING

FACTS ABOUT GLOW PLUGS FUEL

CARBURETOR CONTROLS

STARTING

RUNNING-IN,ADJUSTMENT

8~10

18 19

20 21

CARBURETOR CLEANLINESS

ADJUSTING CHART

INSTALLATION OF THROTTLE SERVO

CARE AND MAINTENANCE

ENGINE EXPLODED VIEW & PARTS LIST

CARBURETOR EXPLODED VIEW & PARTS LIST

THREE VIEW DRAWING

O.S. GENUINE PARTS & ACCESSORIES

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.

•

Never touch, or allow any object to come into contact with, the rotating parts.

Model engine fuel is poison-

•

ous. 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.

WARNINGS

•

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

These engine were designed for model

•

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

Mount the engine in your model securely, fol-

•

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

Install an effective silencer (muffler). Frequent

•

close exposure to a noisy exhaust (especially in the case of the more powerful high-speed engines) may eventually impair your hearing and such noise is also likely to cause annoyance to others over a wide area.

Check the linkage to the throttle arm before

•

each flight. Avoid sudden high r.p.m. immediately after the

•

engine is started, as the clutch will engage and you may be struck by the rotor.

After starting the engine, carry out any needle-

•

valve readjustments after stopping the rotor by closing the throttle to the lowest r.p.m.. Stop the engine before attempting to make other adjustments to the carburettor.

Use an electric starter. The wearing of safety

•

glasses is also strongly recommended. Press the rotor head down securely.

Take care that the glow plug clip or battery

•

leads do not come into contact with rotating parts.

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 rotor. Do not carry loose objects (such as pencils, screwdrivers, etc.) in a shirt pocket from where they could fall through the rotor disc.

For their safety, keep all onlookers (especially

•

small children) well back (at least 20 feet or 6 metres) 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. Hold the rotor securely and keep well clear of spectators.

Warning! lmmediately after a glowplug-ignition

•

engine has been run and is still warm, conditions sometimes exist whereby it is just possible for the engine to restart when turned over WITHOUT the glowplug battery being reconnected. Remember this if you wish to avoid the risk of accidents.

NOTES

Do not attempt to disassemble the recoil

•

starter (if fitted). If you do so, the very strong spring inside will be suddenly ejected. This can be very dangerous.

Do not extend the starter cord more than 45cm

•

(18"). Do not abruptly release the operating handle. Allow the cord to rewind smoothly while still holding the handle.

Pull the operating handle straight out when

•

stating the engine, so that the cord does not rub against the helicopter structure or engine. This will help prevent the cord from being damaged by abrasion or engine heat.

INTRODUCTION

These engines are produced by the world's oldest and largest model engine manufacturing company ; a company that has designed and manufactured all types of engines, large and small : two-stroke, fourstroke, Wankel-rotary, supercharged, twin nand multi-cylinder four-strokes and has also produced more helicopter units than any other maker worldwide. Highperformance motors, designed for small-sized radio-controlled helicopters, the MAX-32SX-H Series is available in a choice of three versions. The standard 32SX-H features ABC cylinder/piston construction, whereas the 32SX-H Ring employs a compression-ring equipped piston, while the 32SX-HX Ring has the addition of an O.S. Recoil Starting System to eliminate the need for a separate electric starter and battery.

The close-fitting ringless piston of the standard 32SX-H will feel tight at the top of its stroke when the engine is cold. This is normal. The piston and cylinder are designed to achieve a perfect running clearance when they reach their normal running temperature.

Note: Because of this initial tightness, a standard

electric starter may have difficulty in rotating the engine when cold, before it has been adequately run-in. In this case, use a hightorque type starter. DO NOT,however, confuse tightness with the symptoms of hydraulic lock caused by an excess of fuel within the cylinder

- often the result of over-priming. Attempting to force the engine to turn over in this condition may cause internal damage. Instead, remove the glowplug,invert the engine and eject surplus fuel from the combustion-chamber.

BASIC ENGINE PARTS

Glowplug

Carburetor Typr 20C

Beam Mount

Needle valve

Propeller nut

Crankshaft

Heatsink Head

Crankcase

Recoil Starter Assembly No.O

Starter Handle

MAX-32SX-HX

INSTALLING THE GLOWPLUG

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

Glow plug

Washer

INSTALLATION

The under-surfaces of all O.S. engine beam mounting lugs are precision machined flat and exactyly parallel to the engine's horizontal axis. It is essential that the engine mounts in the model are also accurately made and aligned. If they are not, they will cause stress and distortion within the engine itself, probably resulting in loss of performance and internal damage. The recommended screws for securing the engine to the engine mounts in the model are 3mm or 4-40 steel Allen type. It is also advisable to use lock washers or LOCTITE to prevent nuts from loosening.

CORRECT

Front view

Top surfaces are in the same plane.

Side view

INCORRECT

Note:

As the recoil starter is of unit construction, re-

1. placement parts are not available. Replacement recoil starters are obtainable only as complete units.

Do not pull the starter cord more than 50cm (20

2. in.). Do not abruptly release the starter knob. Allow the cord to rewind slowly by holding on to the knob.

Pull the knob straight so that the cord does not

3. touch the helicopter body, etc.

Top surfaces are not in the same plane.

Re-align the surfaces as necessary

Top surfaces are not in the same plane.

Engine does not rest firmly.

BEFORE STARTING

Tools, accessories, etc.

The following items are necessary for operating the engine.

1 Fuel

NOTES CONCERNING THE RECOIL STARTER

( 32SX-HX ONLY)

Warning! Do not attempt to disassemble the recoil starter: the very strong spring inside will spring out,

Model glowplug engine fuel of good quality, preferably containing a small percentage of nitromethane.

2 Glowplug

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

which is very dangerous.

3 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.

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

1.5 volt heavy-duty dry battery

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

will overheat and burn out.

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.

4 Plug wrench

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

5 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.

6 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.

For tightening glowplug

Battery leads

Fuel bulb

Fuel pumps

Manual

Electric

+ 22 hidden pages