ocr: INTERNAL COMBUSTION ENGINE AI heat engine where the heat is produced by burning fuel inside the cylinder (like a gas or diesel engine) rather than outside (like a steam or hot air engine). MAIN JET The orifice through which fuel flows to the venturi. The combination of the venturi vacuum and main jet size controls the misture. A convenient property of an oritice and a venturi is that the misture is constant over a fairly wide range of fuel and air flowrates. MIRTURE The ratio of fuel to air being used by the engine. A rich mixture has more fuel in the same amount of air than a lean mixture.
