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.
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.
NOTES This engine was designed for model aircraft. Do not attempt to use it for any other purpose. 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. Mount the engine in your model securely, following the manufacturers' recommendations, using appropriate screws and locknuts.
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. 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.
ABOUT THE ENGINE This is the fourth model from the new FS series of the single cylinder overhead valve four cycle engines. It features a sharp and modern look and broad power band to suit a variety of model types. Newly designed F-5030 silencer minimizes noise with its soft, low-amplitude sound. Threaded header pipe allows adjustments in the distance between silencer and exhaust and exhaust angle. New lubricating system eliminates the need for breather tubing from the crankcase.
BEFORE STARTING Tools, accessories, etc. The following items are necessary for operating the engine. Warning: Make sure that the propeller is well balanced. An unbalanced propeller and/or spinner can cause serious vibration which may weaken parts of the airframe or affect the safety of the radio-controlled system. DO NOT forget the WARNINGS and NOTES on propeller and spinner safety given on front pages.
Fuel Tank Electric Starter and Starter Battery A fuel tank of approximately 220cc capacity is suggested. This allows around 12 minutes flying time, dependent upon the type of fuel used, the size of propeller and on the amount of full-throttle to part-throttle operation throughout the flight. Electric Starter Required when starting 12-Volt lead-acid battery the engine. O.S.
INSTALLATION It is suggested to use as heavy and rigid as possible engine mounting for highest performance and safe running. Conventional wooden mounting beams should be of rigid hardwood and of at least 15mm or 5/8-in square section. Use at least 3mm steel screws, such as Allen type, with locknuts, for bolting the engine to the bearers.. Make sure that the mounting beams are parallel and that their top surfaces are in the same plane.
THROTTLE LINKAGE NEEDLE-VALVE EXTENSION The needle-valve supplied with this engine 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. Needle Valve Extension Cable Set (Code No.
The exhaust outlet of the silencer can be rotated to any desired position in the following manner: Assembly screw 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. Exhaust pressure nipple Baffle Reminder! Model engines generate considerable heat. Do not touch any part of your engine until it has cooled.
PROPELLER There is a risk, particularly with powerful fourstroke engines, of the propeller flying off if the prop nut loosens due to detonation ("knocking") in the combustion chamber when the engine is operated too lean, or under an excessively heavy load. Propeller washer Locknut Obviously, this can be very hazardous. To eliminate such dangers, the O.S. Safety Locknut Assembly was devised.
MIXTURE CONTROLS RELOCATION OF CARBURETOR CONTROLS The carburetor can be turned 180 to reverse the needle-valve and throttle lever position. Intake Manifold Retaining Screw 1. Remove the intake manifold retaining screws and carburetor retaining screws. 2. Rotate the intake manifold 180 gently without removing the carburetor from the intake manifold. 3. Re-install the intake manifold and carburetor retaining screws. Make sure the fitting faces are clean. Do not over-tighten the screws.
STARTING The FS -72 is not equipped with manual choke controls, as it is intended for use with an electric starter only. A high-torque electric starter not only makes starting the engine easier, it dispenses with the need for a choke valve by turning the engine over fast enough to the cylinder automatically. Starting procedure is as follows: Element glows when energized. Pliers Replace the plug when the element does not glow or is burnt out. 1. Fill the fuel tank with fuel.
8. Now disconnect current to the glowplug and gradually close the needle-valve so that the rpm increases. Make adjustments to the needle in small steps. Abrupt changes at this stage are likely to cause the engine to stall. Restart the engine by simply applying the starter with the glowplug re-energized and the throttle at its starting setting. Make sure that the direction or rotation is correct. Electric starter 7.
WARNING: When ground running the engine, avoid dusty or sandy locations. If dust or grit is drawn into the engine, this can have a ruinous effect, drastically shortening engine life in a matter of minutes. 8. With each successive flight, close the needle-valve very slightly until, at the end of about 10 flights, the needle is set for full power. Do not "over-lean" the mixture in an attempt to extract more power. If overheating should be suspected at any time during flight (i.e.
REALIGNMENT OF MIXTURE CONTROL VALVE CARBURETOR CARE & MAINTENANCE In the course of making carburetor adjustments, it is just possible that the Mixture Control Valve may be inadvertently screwed in or out too far and thereby moved beyond its effective adjustment range. If you experience difficulty in obtaining a consistent mixture setting it could be due to foreign debris in the carburetor. Carefully disassemble the carburetor and wash in methanol.
Install an in-line fuel filter between the tank and carburetor to prevent dirt and foreign in the tank from entering the carburetor. Do not close the needle-valve and mixture control valve too far as this will cause a lean setting and over heating of the engine. This can, in turn, create nitromethane oxide leading to internal rusting of the engine. Always adjust the needlevalve slightly on the rich side of peak rpm. Clean these filters periodically.
35 1 2 3 4 5 6 7 8 9 10 11 11-1 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 31-1 32 33 33-1 33-2 33-3 33-4 33-5 33-6 Description Rocker Cover Rocker Arm Retainer (2pcs.) Rocker Support (1pc.) Rocker Arm (1pc.) Tappet Adjusting Screw (1pair) Split Cotter (2pcs.) Valve Spring Retainer (1pc.) Valve Spring (1pc.) Intake Valve (1pc.) Exhaust Valve (1pc.) Cylinder Head (W/Gasket) Cylinder Head Gasket (1pc.) Intake Manifold (1pc.
CARBURETOR EXPLODED VIEW S.M3X3 5 1-2 1-1 1 4 3 2-1 6 2 7 7-2 N.+M3x22 7-1 11 8 9 S.M3x3 9-1 10-1 10 Type of screw C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw N.+M3x6 36 CARBURETOR PARTS LIST No. Code No.
O.S.
MEMO 40 URL : http://www.os-engines.co.jp 6-15 3-Chome Imagawa Higashisumiyoshi-ku Osaka 546-0003, Japan TEL. (06) 6702-0225 FAX. (06) 6704-2722 C Copyright 2008 by O.S.Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan.
