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.
NOTES WHEN APPLYING AN ELECTRIC STARTER Do not over-prime. This could cause a hydraulic lock and damage the engine on application of the electric starter. If over-primed, remove glowplug, close needle-valve and apply starter to pump out surplus fuel. Cover the head with a rag to prevent pumped out fuel getting into your eyes. 8 ABOUT THE ENGINE STANDARD ACCESSOIES This is a high performance two stroke engine designed for sport and aerobatic models. Glow Plug No.
BASIC ENGINE PARTS Glowplug Cylinder head Carburetor Type 40J Cover Plate Propeller washer Beam Mount Propeller nut Crankshaft Crankcase Drive Hub 10 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. BEFORE STARTING Tools, accessories, etc.
Reminder! FUEL 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. The 55AX should be operated on a methanol based fuel containing not less than 18% (volumetric) castor oil, or a top quality synthetic lubricant (or a mixture of both), plus a small percentage (5-20%) of nitromethane for improved flexibility and power.
LONG SOCKET WRENCH WITH PLUG GRIP TOOLS Recommended for easy removal and replacement of the angled and recessed glowplug, the O.S.Long Socket Wrench incorporates a special grip. HEX Screwdriver Necessary for engine installation. 1.5mm, 2.5mm 8mm Phillips Screwdriver No.2, etc. End Wrenches 10mm, etc. SCREWDRIVER Necessary for carburetor adjustments. Needle Nose Pliers Socket Screwdriver 5mm, 5.
How to fasten the mounting screws. ● Hardwood mounting beams 3mm steel nuts Spring washer or lock washer Tighten second nut firmlydown onto first nut. Tighten this nut first. 15mm min. 15mm min. Hardwood such as cherry or maple. Steel washer Make sure that these mounting beams are accurately aligned and firmly integrated with the airframe, reinforcing the adjacent structure to absorb vibration.
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. For this purpose, Needle Valve Extension Cable Set is supplied with the engine.
FUEL TANK LOCATION Suggested fuel tank capacity is approx 350cc. This will allow 10-12 minute flights. Locate the fuel tank so that the center of the carburetor is flush with the center of the fuel tank. Make sure that the tank is well rinsed out with methanol or glow fuel before installation and that the pickup weight is well clear of the bottom of the tank when held vertically. Be sure to use a pressurized fuel system by connecting the muffler pressure nipple to the vent-pipe of the fuel tank.
MIXTURE CONTROLS Two mixture controls are provided on this Carburetor. Needle Valve The Needle Valve When set to produce maximum power at full throttle, this establishes the basic fuel/air mixture strength. The correct mixture is then maintained by the carburetor's built-in automatic mixture control system to cover the engine's requirements at reduced throttle settings. Mixture Control Valve Mixture Control Valve of the carburetor is set at basic position ( a little on the rich side) at the factory.
STARTING Be sure to use an electric starter to start the engine. ! Element glows when energized. Pliers Never fail to check the tightness of screws and nuts, especially engine mounting and moving parts (e.g. throttle lever). Replace the plug when the element does not glow or is burnt out. Starting procedure is as follows: 1. Fill the fuel tank with fuel. When filled, prevent fuel flowing into the carburetor with a commercially available fuel stopper, etc. Release the stopper before starting the engine.
Attention : Do not choke the carburetor air intake when applying the starter. This could cause an excessive amount of fuel to be drawn into the cylinder which may initiate an hydraulic lock and damage the engine. If the engine does not start within 10 repeat applications of the starter, remove the glowplug, check that it glows brightly and that the cylinder is not flooded with fuel. (To eject excess fuel, close needle-valve and apply starter with glowplug removed.) Then try again.
Optimum needle setting(1) Slowly advance the throttle to its fully open position, then gradually close the needle-valve until the exhaust note begins to change. (4cycle to 2-cycle) 4. During subsequent flights, the needle-valve can be gradually closed to give more power. However, if the engine shows signs of running too lean, the next flight should be set rich. After a total of ten flights, the engine should run continuously, on its optimum needle-valve setting, without loss of power as it warms up.
IDLING ADJUSTMENT CHART Start the engine. Make sure that the throttle is fully open. Disconnect the battery leads at mid speed. 20-45 open from maximum r.p.m. setting. Adjust the needle-valve. Close the throttle gradually. The position where the lowest possible r.p.m. ,with steady running, is obtained. Set the idle speed Set the throttle opening by means of the throttle trim on the transmitter so that the lowest practical speed, without risk of the engine stopping,is obtained.
MIXTURE CONTROL VALVE ADJUSTMENT With the engine running, close the throttle and allow it to idle for about five seconds, then open the throttle fully. If, at this point, the engine is slow to pick up and produces an excess of exhaust smoke, the mixture is too rich. Correct this condition by turning the Mixture Control Screw clockwise 15-30 degrees.
SUBSEQUENT READJUSTMENT Once the engine has been run-in and the controls properly set up, it should be unnecessary to alter the mixture settings; except to make minor adjustments to the Needle-Valve occasionally, to take account of variations in climatic conditions. The use of a different fuel, however, particularly one containing more, or less, nitromethane and/or a different type or proportion of lubricating oil, is likely to call for some readjustment of the Needle-Valve.
Symptom Engine fires intermittently but does not run. Engine fires once or twice, then fails to fire. Engine starts but rpm decreases and engine eventually stops. Engine starts, rpm increases and engine cuts out. Engine stops when the current to the glowplug is disconnected after starting. Factor Corrective action Cause . . . . . 3 Incorrect heating of glowplug. Over priming. . . . . . . . . 1 Sluggish rotation. . . . . . . 2 Glowplug battery discharged. 3 Insufficient priming.
When the engine is not to be used for some months (for example, as between flying seasons), a worthwhile precaution is to remove it from the airframe and, after washing off the exterior with alcohol (not gasoline nor kerosene), remove carefully the carburetor with intake pipe, glow plug and all silicone tubing and put them safely aside. Then, immerse the engine in a container of alcohol. Rotate the crankshaft while the engine is immersed.
ENGINE EXPLODED VIEW ENGINEN PARTS LIST C.M3x15 1 17 2 39 38 4 3 15 5 6 13 C.M3x8 12 10 9 7 16 11 14 8 Type of screw C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw No. Code No.
CARBURETOR EXPLODED VIEW N.+M3x6 3 3-1 3-2 7 1 4 2 5 7-4 7-1 6 7-5 7-2 7-3 N.+M3.5x6 S.M3X3 8 9 Type of screw C...Cap Screw M...Oval Fillister-Head Screw F...Flat Head Screw N...Round Head Screw S...Set Screw 40 CARBURETOR PARTS LIST No. Code No.
O.S. GENUINE PARTS & ACCESSORIES O.S.GLOW PLUG No.8 RADIAL MOTOR MOUNT (71913100) SPINNER NUT 1/4"-28(L) (23024009) (71608001) PROPELLER NUT SETS FOR 2C SPINNER 1/4"-M5 (73101020) A5 (71605100) LONG PROPELLER NUT SETS 1/4"-28 SILENCER EXTENSION ADAPTORS NON-BUBBLE WEIGHT NON-BUBBLE WEIGHT (25425600) (71531000) S (71531010) (73101000) 42 SUPER FILTER (L) (72403050) CAP SCREW SETS (10pcs.
THREE VIEW DRAWING 100.5 92 8.93 cc / 0.545 cu.in. 23.0 mm / 0.906 in. 21.5 mm / 0.846 in. 2.000-17.000 r.p.m. 1.75 ps / 16.000r.p.m. 404 g / 14.25 oz. 37.1 4 22 E-3020 44 Displacement Bore Stroke Practical R.P.M. Power output Weight 38.1 SPECIFICATIONS 22 E-3010 Silencer Assembly 120 g / 4.23 oz. 17.5 36 87.7 21 36.7 72.6 UNF1/4-28 18.5 28.5 31.7 22.6 43.2 3 42.5 27.2 36 51 60.4 112.6 25 Dimensions(mm) 44 URL : http://www.os-engines.co.
