Most RC airplane and car engines are two-stroke engines. The engine has a single piston and no valves. Air and fuel are mixed in the carburetor and burned in the cylinder. These simple engines can be very temperamental and difficult to start at times. There are a few steps you should take to help ensure that you spend more time enjoying your hobby than tinkering with your engine

Oil Maintenance

• In larger engines, oil is set apart in a separate compartment and is pumped through the system as needed. However, 2-stroke engines have neither the room nor the capability to pump oil, such a different type of oil is used in these engines. Do not use the thick 4-stroke lubricating oil in 2-stroke engines. Instead, mix in lighter oils rated for 2-stroke engines with the gasoline itself. As the gasoline is drawn into the engine, the oil flows with it and lubricates the engine parts before it burns away with the fuel. Thicker fuels will ruin the combustion chamber, so use lighter lubricants.

  There are two different choices for 2-stroke oil: synthetic and non-synthetic. Non-synthetic oils tend to be more environmentally friendly, so use these if you want an eco-friendly alternative. Use synthetic oils if you want your engine to last a little longer or if you want to avoid cleaning it as often.

Decarbonizing

• Because the oil is mixed in with the gas in a 2-stroke engine, combustion tends to produce carbonization more easily than in larger engines. This means that deposits form more quickly and need to be cleaned away more often, so decarbonization is very important. Begin by removing the high voltage cable and spark plugs, then take off the four to six cylinder head nuts. Support the cylinder and carefully pry off the cylinder head, being carefully to damage neither seals nor the head itself.

  Soak the head in a solvent to loosen and remove the carbon build-up. Use gasoline, paint remover or a similar chemical. Degrease and clean the cooling fins. Use a small brush, such as a toothbrush, to scrape away the deposits that have been loosened. Use a small scraper or toothbrush to reach corner deposits but do not scratch the head. Use the same process for other parts of the cylinder.