Where must a BFA be attached on inboard gasoline engines with carburetors?

Where must a BFA be attached on inboard gasoline engines with carburetors?

• A. On the exhaust manifold
• B. On the fuel line
• C. To air intake on top of the carburetor
• D. On the cooling system

Answer: (C)

Backfire prevention in carbureted inboard engines relies on placing a flame arrestor where the air enters the engine. The BFA is attached on the air intake on top of the carburetor, so any flame traveling backward through the intake has to pass through the arrestor, where it is quenched and blocked from reaching the carburetor interior. This placement directly protects the carburetor and intake manifold from ignition caused by backfires. Mounting a BFA on the exhaust manifold, fuel line, or cooling system wouldn’t stop backfire flames from traveling into the carburetor, which is why those locations aren’t appropriate.

Backfire prevention in carbureted inboard engines relies on placing a flame arrestor where the air enters the engine. The BFA is attached on the air intake on top of the carburetor, so any flame traveling backward through the intake has to pass through the arrestor, where it is quenched and blocked from reaching the carburetor interior. This placement directly protects the carburetor and intake manifold from ignition caused by backfires.

Mounting a BFA on the exhaust manifold, fuel line, or cooling system wouldn’t stop backfire flames from traveling into the carburetor, which is why those locations aren’t appropriate.