It is of vital importance, before attempting to operate your engine, to read the general 'SAFETY INSTRUCTIONS AND WARNINGS' section on pages 2-4 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.
WARNINGS SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE 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. Remember that your engine is not a " toy ", but a highly efficient internal-combustion machine whose power is capable of harming you, or others, if it is misused or abused. As owner, you, alone, are responsible for the safe operation of your engine, so act with discretion and care at all times.
NOTES 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 carburetor.
ABOUT THE ENGINE The FR7-420 (Sirius7) is a seven-cylinder radial overhead-valve four-stroke-cycle engine of 70cc displacement. The engine maintains the same features of stress free starting, super smooth idling and high torque power which is always the hallmark of O.S. large size multi-cylinder engines. With its finely detailed design and outstanding scale appearance and sound, the engine's quality is second to none.
Intake Pipe Rocker Cover Cylinder Head Back Plate Exhaust Pipe Carburetor Type 80T 8 INSTALLATION Needle-valve extension It is essential that the firewall is strong and rigid (e.g. at least 15mm thick) and firmly integrated with the structure of the aircraft. 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.
Exhaust pipe Carburetor cleanliness Exhaust pipe becomes very hot while running and right after running, make sure it does not touch the model and never allow hand and body to touch it. It is recommended that the 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 carburetor. Check the tightness of locknuts while the engine is warm after the first flight.
GLOWPLUG Since the compatibility of the glowplug and fuel may have a marked effect on performance and reliability, it is suggested to use the O.S. Type F plug when it is necessary to replace. Carefully install plug finger-tight, before final tightening with the correct size plug wrench. 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.
PROPELLER The choice of propeller depends on the design and weight of the aircraft and on the type of flying in which you will be engaged. Determine the best size and type after practical experimentation. As a starting point, refer to the props listed in the accompanying table.
GLOWPLUG HEATING Glowplug battery Glowplug leads The engine uses seven plugs (O.S. Type F). It is suggested to use a commercially available glowplug heater intended for multi-cylinder engines. This enables the glowplug heat to be turned ON and OFF at the transmitter and also apply heat at idle. A pulse type that heats the plugs with lower current drain is suggested. Make sure that no part of the wiring touches any part of the engine, or the wire covering may be melted which causes short-circuit and fire.
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. Lubrication The crankcase breather hole is located at the back of the engine and is fitted with a brass nipple. Fit a length of silicone tubing of approx. 2.5mm I.D. to this nipple to conduct away the small amount of oil that escapes through the breather. Model engine fuel is also highly flammable.
8. Now disconnect the glowplug battery. 5. Starting with an electric starter. Make sure that the direction of rotation of the starter is correct. 9. Adjust the needle-valve Connect the glowplug battery. With fully throttle, close the needle-valve gradually to increase the engine rpm. It is suggested to use a tachometer. Apply the electric starter. Abrupt adjustment of the needle-valve may cause the engine to stop, especially when it is new and insufficiently run-in. 6.
RUNNING-IN ("Breaking-in") Obtain an 22x10 or 23x8 propeller for running-in. 1. Running-in on the ground 2. Running-in in the air Start the engine 1 Start the engine ↓ Fly the model. Set the needle-valve approx 45 open from optimum position (approx. 45 open from maximum r.p.m.). Set the needle-valve 200-300r.p.m. lower than maximum r.p.m. setting and run approx, 10 seconds. (It is suggested to use a tachometer.) NOTE: Avoid prolonged heavy load flight.
Yes. OK Does the engine regain full power immediately? No. Apply full throttle. Does the engine stop? One of the cylinders ceases firing. Run at idle speed for 15 seconds. Attention: Do not leave the battery connected while adjusting the carburetor. Do not move needle-valve while adjusting other controls. Adjustment should be carried out after stopping the engine. Close the throttle. Check mixture adjustment at idle speed. Make sure that all cylinders are firing. Yes.
FLIGHT & MAINTENANCE Checking before flight Make sure that all seven cylinders are firing. Install a fuel filter to prevent dirt and dust in the fuel container from entering the fuel tank. O.S. Super Filters (L) is available as an optional extra. Sound at full throttle changes when one or two cylinders are not firing. With a propeller which the engine runs approx. 6,000rpm with full throttle, one misfiring cylinder will drop approx. 500rpm and two misfiring cylinders will drop approx. 1,000rpm.
VALVE CLEARANCE ADJUSTMENT ALL O.S. four-stroke engines have their valve (tappet) clearances correctly set before they leave the factory. However, if, after many hours of running time have been logged, a loss of power is detected, or if the engine has to be disassembled or repaired as a result of an accident, valve clearances should be checked and readjusted, as necessary, with the aid of the O.S. Valve Adjusting Tool Kit. 3. The standard valve clearance, on both inlet and exhaust valves, is between 0.
ENGINE EXPLODED VIEW & PARTS LIST 8 C.M2.6x10 C.M3.5x18 9 1 C.M3.5x8 7-1 7 58 36 7-2 3 5 32 10 4 11 6-5 6-4 6-3 6-1 20-1 30 27 31 57 M2.6x13.1 C.M2.6x13 6-2 N.+M3x22 28 20 20-2 C.M2.6x7 33 29 12 13 6 35 34 C.M3.5x15 2 C.M3x8 C.M4x10 C.M2.6x7 52 54 56 52-1 19 55 25 49 26 21 46 C.M4x15 53 23 18 48 24 22 41 42 43 44 46 17 16 C.M4x25 45 47 50 51 59 C.M4x15 C.M4x25 40 14 38 60 39 CAP SCREW SETS (10pcs./sets) 15 37 Type of screw 15-1 C...
EXPLODED VIEW & PARTS LIST S.M3x3 4 1 5 2-1 6 2 7 3 7-2 7-1 8 10 9 N.+M3x22 9-1 Description No. Code No. 1 2 2-1 3 4 5 6 7 7-1 7-2 8 9 9-1 10 47181970 27381940 26711305 47181100 22681953 46115000 45581820 47181600 46066319 24881824 47181200 22081408 22081313 45581700 Needle Assembly Needle Holder Assembly Ratchet Spring Carburetor Body Fuel Inlet (Nipple No.1) Carburetor Rubber Gasket Roter Guide Screw Mixture Control Valve Assembly "O" Ring (2pcs.) "O" Ring (2pcs.
THREE VIEW DRAWING Specifications Displacement Bore Stroke PracticalR.P.M. Output Weight 9.95 cc x 7 / 0.607 cu.in. x 7 24.0 mm / 0.945 in. 22.0 mm / 0.866 in. 1,500-7,000r.p.m. 3,167 g / 111.71 oz. 36 36 72 72 122 UNF3/8-24 230 158.5 Dimensions (mm) 34 URL : http://www.os-engines.co.jp C Copyright 2010 by O.S.Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan. 6-15 3-Chome Imagawa Higashisumiyoshi-ku Osaka 546-0003, Japan TEL. (06) 6702-0225 FAX.
