Figure 3-20. - Synthetic rubber oil seals.

motion. The principal moving parts are the piston assembly, the connecting rods, the crankshaft assembly (including flywheel and vibration dampener), the camshaft, the valves, and the gear train.

Burning of the air-fuel mixture within the cylinder exerts a pressure on the piston, thus pushing the cylinder down. The action of the connecting rod and crankshaft converts this downward motion to a rotary motion.