Micro engines What is a GLOW engine? R/C models get power from various modes. Gliders, for example, do not need a power source other than what nature provides. But they are the exception. Normally all flying models, helicopters, boats and cars need something to provide movement. Electric models use small motors powered by a battery pack. They should not be confused with GLOW ENGINES that are micro engines, and are used to power all kinds of models Muffler Glow Plug Minimum speed screw )idle)screw Max Screw Cylinder Carburetor Needle valve Revolving valve Shaft Venturi A 7,5 cc R/C engine R/C models can use either 2 or 4 stroke engines, sized to match the type of model. The typical and most popular range of cubic capacity in model engines is from.049 cu. in. (cubic inches) up to 1.5 cu. in. (about 0,8cc to 30cc), so a large variety of sizes can satisfy all requests for any aeromodeller. The glow plug
2 Stroke Vs 4 Stroke It is possible to buy both 2 or 4 stroke Glow type engines. The question is: Which one is better for me? 2 Stroke simply means that the engine burns the fuel every time the piston goes down-once per turn. Normally they are the best starting point for who want to get started in the model field. The 2 strokes are easy to use and are simpler and more powerful at equal weight and size. 27 cc Glow engine 2,5cc tem racing Diesel engine 4 Stroke engines burn the fuel one time for every two revolutions, just like the engine of your car. The fuel consumption of this kind of engines is less than 2 strokes and have a more realistic sound. They are more expensive to make, are a bit more difficult to adjust and need more maintenance. Valves Rocker Arm Exhaust Pushrod Camshaft. Piston A 4 stroke engine Main Shaft
How run a Glow engine Glow engines use a simply system to ignite the fuel. A special glow plug instead a common spark plug is used, and the filament is heated to red hot by a 2 volt battery. The filament is made of a special alloy (platinum + rhodium + Iridium). After the engine is started the heat of the burning fuel keeps the filament hot. In the R/C engine a carburettor mixes the fuel with air and controls the flow of fuel and air into the cylinder. After burning the exhaust gas will exit from the exhaust port. The carburettor unit is an important item, and consists of several parts used for different adjustments and regulations. The revolving valve: this valve opens and closes the air hole in the venturi pipe and controls the minimum and maximum RPM of the engine. The main needle valve: the needle controls the quantity of inlet fuel and therefore the air/fuel ratio. The idle mixture needle: this screw controls the quantity of fuel at low engines RPM. When the needle adjustments are done correctly the engine will run well at all RPM. In C/L (control line) engines there is only a needle valve the control the air/fuel ratio. C/L engine Venturi Needle valve
These engines are wide open all the time and performance at idle and low speed does not matter, so there is no mixture-flow throttle valve as there is in an R/C engine. Another kind of engine the DIESEL. Compression screw Old Time Diesel engines This kind of engine doesn t use glow plugs. Instead it relies on the heat of compression to ignite a special type of fuel. These engines are mostly used for Team racing or Combat competition and do not use much fuel for the power produced. The maximum size is 3,5 cc.
What kind of maintenance will my engine need? If you take care of your engine it will run well for long time.. The proper maintenance is not difficult and the basic rules are as follow: - Keep the engine clean and protect it from dirt and dust. - Use fuel suggested by the maker, with the proper quantity of oil and additives. - Lubricate and clean inside after use with light petrol (kerosene)-always! - Check and if necessary change the shaft ball bearings. They are a key point for the best performance of the engine. Check the bearings by disassembling the piston liner and connecting rod. The crankshaft must turn freely without tight places or noise and always stop with the con rod pin on top. To remove the bearings heat the crankcase a little. The crankcase will grow slightly and the bearings can then be removed easily. Insert the new bearing and let the case cool slowly.