FAA Aviation Mechanic Airframe (AMA)Fuel, Cabin and Ice Control SystemsMedium
A mechanic is troubleshooting a reciprocating engine fuel system and locates a gascolator installed at the lowest point of the system between the fuel selector valve and the carburetor. What is the function of this component?
- AMeter fuel flow proportional to engine RPM
- BRegulate fuel pressure delivered to the carburetor
- CTrap water and sediment before fuel reaches the carburetor
- DPrevent vapor lock during hot engine starts
Show answer & explanationAnswer & explanation
Correct answer: C. Trap water and sediment before fuel reaches the carburetor
The gascolator is a fuel strainer/sediment bowl positioned at the system's lowest point so gravity allows water and heavy particles to settle out before the fuel reaches the carburetor.
Why the other options are wrong
- A. Fuel metering is done by the carburetor or fuel control unit.
- B. Pressure regulation is performed by a fuel pressure regulator, not the gascolator.
- D. Vapor lock prevention is unrelated to the gascolator's filtering function.
Gascolator (Fuel Strainer)
A fuel system component located at the lowest point that traps water and sediment via a settling bowl before fuel reaches the carburetor.
- Installed at the system's lowest point
- Equipped with a clear bowl and drain for inspection
- Common on reciprocating engine fuel systems
Memory trick: Gascolator = gravity's collector, catching junk before the carb.