O.S. Engines 21RG-MX 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.

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

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

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

CONTENTS

SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE

INTRODUCTION, BASIC ENGINE PARTS INSTALLATION NOTES CONCERING

THE RECOIL STARTER GLOWPLUG TOOLS, ACCESSORIES, etc. CARBURETTOR CONTROLS

STARTING & INITIAL RUNNING-IN('Breaking-in)

ADJUSTMENT

13 16

2~5

CARE AND MAINTENANCE CHECKING OF THE ENGINE

TROUBLE SHOOTING WHEN THE

ENGINE FAILS TO START ENGINE EXPLODED VIEW

ENGINE PARTS LIST CARBURETTOR EXPLODED VIEW & PARTS LIST

O.S. GENUINE PARTS & ACCESSORIES

THREE VIEW DRAWING MEMO

20~21

22 23

26~27

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 applies basically to ALL MODEL ENGINES and 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 propeller and do not crouch over the engine when it is running.

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 en-

•

closed 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 boats.

•

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.

Fit an effective silencer (muffler). Frequent

•

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

For their safety, keep all onlookers

•

(especially small children) well back (at least 20 feet or 6 meters) when preparing your model for running.

Take care that the glowplug clip or battery

•

leads do not come into contact with the propeller or any other rotating parts. Also check that the linkage to the throttle arm is secure.

If your engine does not have a built-in recoil

•

starter, use an electric starter. The wearing of safety glasses is also strongly recommended.

When handling the boat immediately prior to

•

launching, be especially cautious. Keep the propeller and other rotating parts away from you.

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.

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 it is rotated over compression WITHOUT the glowplug battery being reconnected.

If your engine is fitted with a recoil starter,

•

pull the operating handle straight out when starting the engine, so that the cord does not rub against the hull or engine. This will help prevent the cord from being damaged by abrasion or engine heat.

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.

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.

The O.S. "RG Series" is a high-performance water-cooled marine engine for small radiocontrolled boats, especially sport type hulls. A companion model, the MAX-21RG-MX incorporating a recoil starter system is also available.

Standard accessories

Glow Plug No.8

Flywheel No2E

Exhaust Header Pipe

NOTE

With this engine, the piston 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 temperatures.

We do not recommend running your boat

•

on the sea, or in any other saltwater environment. Under such conditions, it is difficult to prevent the engine from becoming corroded and, eventually, inoperative.

BASIC ENGINE PARTS

Water Cooled Head

Carburettor Type 20J

Cranshaft

INSTALLING THE GLOWPLUG

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

Glow Plug No.8

Beam Mount

Crankcase

MAX-21RG-MX

Starter Handle

Recoil Starter Assembly No.5

Glow plug

Washer

INSTALLATION OF THE CARBURETOR

As delivered, the engine has its carburetor lightly fitted into its intake boss. Secure it as follows.

Loosen the retainer screw, rotate the carburetor to

1. its correct position and make sure that it is pressed well down into the intake boss, compressing the rubber gasket, before retightening screw.

Rotate the retainer screw gently until it stops, then

2. tighten a further 90-120˚. Do not overtighten the screw as this will damage the carburetor body.

Rotate the retainer nut gently until it stops.

Tighten a further 90-120˚

INSTALLATION OF THE FLYWEEL

Insert the taper collet on the crankshaft, taking care not to push the crankshaft to the cover plate end.

Crankshaft

Flywheel

Taper Collet

INSTALLATION OF THE EXHAUST HEADER PIPE

Select the screw holes according to the model.

INSTALLATION

Make sure that the engine mounting beams in the

hull are parallel, with their top surfaces in the same plane. If they are not, the engine will not rest firmly as the engine mounting faces (undersides of the mounting lugs) are precision machined to be flat and in the same plane. Poor installation may not only cause vibration, erratic running and loss of performance, but may also damage the engine itself by deforming the crankcase, cylinder, etc.

The mounting beams and adjacent hull structure

should be as rigid as possible so that the engine may develop its full performance. Use 3mm steel screws, such as Allen socket-head type, with locknuts, for bolting the engine to the mounting beams.

If the holes in the mounting beams do not align

exactly with the engine's mounting lugs, enlarge them slightly with a needle file so that the mounting screws pass through the holes smoothly without being forced.

Chamfer inside edges of bearers.

NOTES CONCERNING THE RECOIL STARTER

REMINDER!

Do not attempt to disassemble the recoil

◆

starter. 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

◆

starting the engine, so that the cord does not rub against the vehicle body or engine.This will help prevent the cord from being damaged by abrasion or engine heat.

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