Which type of fuel system is most commonly used in small gas engines?

The carburetor is the most commonly used fuel system in small gas engines primarily because of its simplicity, ease of repair, and cost-effectiveness. Carburetors mix air and fuel to create a combustible mixture for the engine. This traditional system has been widely utilized in a variety of outdoor power equipment, including lawn mowers, chainsaws, and snow blowers, due to its reliability and straightforward mechanical design.

Carburetors can operate effectively across a range of operating conditions and are less complex than fuel injection systems, making them ideal for small engines where compact size and ease of maintenance are critical. They rely on the difference in air pressure created by the engine's intake, which draws fuel into the airflow, enabling the proper mixture necessary for combustion.

While other systems like computer controlled systems and fuel injection offer advantages in efficiency and emissions, they are generally found in larger, more advanced engines rather than the smaller gas engines typically used in outdoor power equipment. Spill dams, on the other hand, are not related to fuel delivery but rather are safety measures to prevent spills, and thus do not serve as fuel systems.