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O.S. Engine FS-120S-E Owner's Instruction Manual

Manual is about: CYCLE ENGINE

Summary of FS-120S-E

  • Page 1

    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 familia...

  • Page 2: Warnings

    2 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. If...

  • Page 3: Introduction

    4 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 rota...

  • Page 4: Choke Valve

    6 the needle-valve and throttle lever locations are interchangeable by reversing the carburetor. This can be done as follows: remove the carburetor carefully by unscrewing the two screws which secure both carburetor and choke valve. (see photo 1.) if the carburetor remains difficult to remove, sligh...

  • Page 5: Needle-Valve Extension

    8 needle-valve extension the needle-valve supplied with this engine is designed to accept an extension so that, when the engine is enclosed in a cowling, the needle-valve may be adjusted from the outside. An l-shaped rod, of appropriate length, may be inserted in the needle-valve knob center hole an...

  • Page 6: Fuel

    10 fuel the fs-120s-e should be operated on a methanol based fuel containing not less than 18% castor-oil, or a top quality synthetic lubricant (or a mixture of both), plus a small percentage (5-15%) of nitromethane for improved flexibility and power. The carburettor is adjusted at the factory for a...

  • Page 7: Carburettor

    12 carburettor the needle valve this is used to establish the fuel/air mixture strength required for full power when the throttle is fully open. The mixture control valve (mixture control screw) this is used to establish the mixture strength required for steady idling and a smooth transition to medi...

  • Page 8: Running-In (Continued)

    14 start and adjust the engine as detailed in the starting instructions. Now open the throttle fully and run the engine for no more than 5 seconds with the needle-valve tuned to produce near maximum r.P.M., then, immediately, slow the engine down again by opening the needle-valve approximately 0.5 t...

  • Page 9: Valve Adjusting

    16 note: valve clearances of all o.S. Four-stroke-cycle engines must be checked and reset only when the engine is cold. Procedure is as follows. Remove the cover from the rocker-box on top of the cylinder-head, using the correct size allen hex key. 1. （Ⅰ） turn the propeller counter-clockwise until c...

  • Page 10: Care and Maintenance

    18 care and maintenance to ensure that you obtain long life and peak performance from your engine, observe the following. Avoid running the engine under dusty conditions. If necessary, lay a sheet of plywood or hard-board in front and under the nose of the model when starting the engine. Foreign mat...

  • Page 11: Exploded View

    20 exploded view type of screw c...Cap screw m...Oval fillister-head screw f...Flat head screw n...Round head screw s...Set screw 1 2 3 3-2 3-1 4 4-1 4-2 5 5-4 5-3 5-2 8 5-1 6-4 6-3 6-2 6 6-1 7 9 10 11 12 13 14 15 16 17 21 27 28 28-2 28-1 28-2 29 18 19 20 22 23 32-1 32 33 31 30 24 26 25 24 c.M3x8 c....

  • Page 12: Carburetor Exploded Views

    22 the specifications are subject to alteration for improvement without notice. Carburetor exploded views & parts list 1 1-1 2 3 3-1 4 5 6 7 8 10 11 9 9-1 9-4 9-5 9-2 9-3 s.3x3 n.+m3x22 s.3x3 45581700 45581820 26711305 27381940 26381501 24981837 45581970 27481900 22681953 22381300 45515000 45581100 ...

  • Page 13: Memo

    24 memo c copyright 2003 by o.S.Engines mfg. Co., ltd. All rights reserved. Printed in japan. Tel. (06) 6702-0225 fax. (06) 6704-2722 6-15 3-chome imagawa higashisumiyoshi-ku osaka 546-0003, japan url : http://www.Os-engines.Co.Jp un eq ua lle d q uality precision & pe rfor m an ce es tab lishin g t...