How a BFA works

How a BFA works

• A. Filters fuel vapors
• B. Increases engine speed
• C. Converts exhaust gas
• D. Cools and quenches flame by forcing heat between closely spaced metal vanes or screens to absorb the heat, removed on the triangle side

Answer: (D)

Backfire flame arrestor works by cooling and quenching any flame trying to travel back into the carburetor air intake. It uses a dense arrangement of metal vanes or screens; when a flame front from a backfire encounters these narrow passages, heat is absorbed by the metal. The flame temperature drops below what is needed to sustain combustion, so the flame cannot pass through to the intake. This is why the device is effective at stopping backfire from reaching the carburetor. It isn’t about filtering fuel vapors, changing engine speed, or converting exhaust—those aren’t the purposes of a flame arrestor.

Backfire flame arrestor works by cooling and quenching any flame trying to travel back into the carburetor air intake. It uses a dense arrangement of metal vanes or screens; when a flame front from a backfire encounters these narrow passages, heat is absorbed by the metal. The flame temperature drops below what is needed to sustain combustion, so the flame cannot pass through to the intake. This is why the device is effective at stopping backfire from reaching the carburetor.

It isn’t about filtering fuel vapors, changing engine speed, or converting exhaust—those aren’t the purposes of a flame arrestor.