If you were a teenager in the 1980s, you likely became familiar with a carburetor when you learned how to drive the family car. The float-type carburetor used in automobiles has since given way to fuel injection systems. But in small piston aircraft, fuel injection systems haven’t fully proliferated, and carburetors still rule the land.
The carburetor mixes aviation fuel and air as part of the combustion process that powers the engine. It atomizes the mixture and also provides a way of controlling engine speed through throttling of intake air. The carburetor ensures that the right ratio of air and fuel is available to the engine at the appropriate times.
A carburetor isn’t easily visible even when you open up the cowling, because it is generally positioned at the bottom of the engine. This placement is intended to keep fuel from dripping onto a hot engine. The carburetor’s five critical parts are the float, float chamber, the main discharge nozzle, the venturi, and the throttle valve.