Two-stroke engines are commonly used in small hand held power machinery such as chain saws, weed eaters, brush cutters and power augers. In the two-stroke engine, lubrication is generally provided by oil mixed with the fuel. Four-stroke engines have a separate reservoir for oil. Gasoline engines intake both air and fuel into cylinders. Compression a. Diesel engines compress air only.
Gasoline engines compress both air and fuel within the cylinders.
Ignition a. Diesel engines ignite the air-fuel mixture spontaneously, due to the heat of compression. Gasoline engines ignite the fuel-air mixture with a spark from the spark plug. Some diesel engines remove exhaust with a blower in addition to removing it with the upward motion of the piston. C. Basic design concept 1. A two-stroke engine utilizes one revolution of the crankshaft between each power impulse.