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.
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 • After starting the engine, carry out any needle- These engine were designed for model helicopters. Do not attempt to use it for any other purpose. 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 carburetor. • Mount the engine in your model securely, following the manufacturers' recommendations, using appropriate screws and locknuts. • Use an electric starter.
Notes on installing cooling fan and clutch Application is as follows: Remove the crankcase rear cover plate from the engine and rotate the crankshaft to the bottom dead center (BDC) position. Do not use a tool which locks piston when installing a cooling-fan and clutch, or top of the piston may be damaged. Also, do not insert a screw driver or the similar into the exhaust port.
Note on heating the glow plug Example The heatsink head on the engine is treated with Alumite which does not conduct current. Therefore, when heating a glow plug, connect one lead to the glow plug and the other to the head of cover plate retaining screw. 8 INTRODUCTION This is a high performance engine expressly designed for F3C competition. The engine uses the same mounting hole spacing as the O.S. 61SX-H RING WC making them interchangeable.
BEFORE STARTING In case of 1.5volt dry cell Tools, accessories, etc.The following items are necessary for operating the engine. Battery leads Items necessary for starting Glow Plug O.S. No.8 is supplied with the engine. 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.
TOOLS Hex Wrench Long Socket Wrench With Plug Grip Necessary for engine installation. 1.5mm, 2mm, 2.5mm, 3mm Recommended for easy removal and replacement of the angled and recessed glowplug, the O.S.Long Socket Wrench incorporates a special grip. Phillips Screwdriver 8mm No.1, No.2, etc. Screwdriver End Wrenches Necessary for carburetor adjustments. No.1, No.2, etc 8mm, 13mm, 14mm, etc. Socket Wrenches Needle Nose Pliers 5mm, 5.
INSTALLATION OF THE STANDARD ACCESSORIES 2. Insert the carburetor rubber gasket on the carburetor body securely. Then, insert the carburetor in the crankcase. INSTALLATION OF THE CARBURETOR 1. Insert the carburetor retainer as illustrated. Unscrew the retainer screw a little. JAPAN Carburetor Rubber Gasket Note: In case it is hard to insert the carburetor in the crankcase, apply oil on the carburetor body. Do not force it, or damage the carburetor body and/or crankcase. Carburetor Retainer 3.
INSTALLATION OF THE ENGINE CORRECT 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.
C The Medium Speed Needle Valve This is an extra control that can be brought into play, if necessary, after adjusting A and B above. It provides the means of fine-tuning mixture strength over that all-important part of a helicopter's throttle range where the model is flying in, or near, the hovering mode. CARBURETOR CONTROLS With a fixed-wing model, power failure is rarely a serious threat to the safety of the aircraft since it can usually glide down to a safe landing.
STARTING 3. Preparation of the starter Install the starting shaft to the starter securely. Improper installation will allow the shaft to swing creating a dangerous situation. Be sure to use a muffler pressurized fuel feed. Use the same fuel as you intend to employ for actual operation of your model. 1. Opening and closing of the Needle-Valve Turn the needle clockwise to close the needle-valve, and turn the needle counter-clockwise to open the needle-valve as shown in the sketch. Close 4.
RUNNING-IN ("Breaking-in") ADJUSTMENT All internal-combustion engines benefit, to some degree, from extra care when they are run for the first few times ー known as running-in or breaking-in. This is allows the working parts to mate together under load at operating temperature. However, because O.S.
After about 10 seconds of idling, open the throttle to 'float' the model. lf the transition is smooth, the idle mixture is O.K. If the symptoms of either rich or Iean running are observed, readjust the Idle Mixture Control Screw accordingly. Maximum 2. Having provisionally set the idle mixture, the next step is to adjust the mixture for hovering flight. Hover the model and actuate the throttle to observe response over the medium speed range.
SUBSEQUENT READJUSTMENTS CARBURETOR CLEANLINESS Once the engine has been run-in and the carburetor controls properly set up, it should be unnecessary to alter the mixture settings, except to make minor changes to the Main (High-Speed) Needle Valve occasionally, to take account of differences in climatic condisitions.
ADJUSTING CHART High Speed Needle Valve - 2 turns opened from fully closed position. Medium Speed Needle Valve - 2 turns opened from fully closed position.
INSTALLATION OF THROTTLE SERVO After the engine is installed in the helicopter, please observe the following recommendations when linking the throttle servo to the carburetor. Servo output arm 27m m Throttle arm Locate the servo so that its output arm and the throttle pushrod are, as close as possible, directry in line with carburetor's throttle arm, as shown. Throttle control rod A and B should be equal length.
Symptom TROUBLE SHOOTING Engine fails to fire. Corrective action Cause Fuel tank is empty. Fuel not reaching the engine. Fill the tank with fuel and repeat Priming procedure. Glowplug element is burnt out. Glowplug battery discharged Replace glowplug. Recharge or replace the battery. Clogged fuel filter Silencer inside is dirty. Clean or replace fuel filter. Clean inside silencer. Over priming Remove glowplug and pump excess fuel. Fuel tubing is disconnected.
Symptom Unstable idle Corrective action Cause Unsuitable glowplug Use suggested glowplug in the instructions. Unsuitable fuel Do not use extremely high nitro or low oil fuel. Silencer is disconnected or has play Install silencer securely. Symptom Not reaching expected peak r.p.m. Corrective action Cause Insufficient warming up or running-in. Set the needle only after warming up. Complete running-in. Silencer or manifold is not securely connected or disconnected.
ENGINE EXPLODED VIEW ENGINE PARTS LIST C.M3x15 No. Code No. 1 2 3 16 34 5 35 4 6 7 C.M3x12 17 8 15 C.M2.6x18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 29064000 29063100 29503400 29063200 27006000 27917000 29505010 29183000 45010002 46120000 26731002 23981700 29061000 27930000 29062000 29061400 29067000 71608001 27708200 41621100 Description Heatsink Head Cylinder Liner Piston Ring Piston Piston Pin Piston Pin Retainer (2pcs.
CARBURETOR EXPLODED VIEW C.M3x8 1-1 8 1 4 2 8-3 8-1 8-6 5 8-4 3-3 6 8-5 8-2 7 10 9-4 9-2 9-3 3-2 3-1 9-1 9 Type of screw C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw 3 36 CARBURETOR PARTS LIST No. Code No.
O.S. GENUINE PARTS & ACCESSORIES GLOWPLUG SUPER FILTER IN-FLIGHT CONTROL NEEDLE VALVE DRIVE HUB ASSEMBLY (w / woodruff key) No.8 (L) (72403050) (71705000) (71608001) Drive Hub (27708010) Woodruff Key A5 (27708200) (71605100) CRANKSHAFT CLAMP 91 (For 91SZ-H) LONG SOCKET WRENCH WITH PLUG GRIP (71530510) (71521000) LOCK WASHER (10set) CAP SCREW SET M3x12 (10pcs.) (79871140) M4 (55500003) M3x15 (79871150) The specifications are subject to alteration for improvement without notice.
MEMO 40 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 C Copyright 2005 by O.S.Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan.
