Required Equipment

What is the purpose of a backfire flame arrestor on an inboard gasoline engine?

Answer

To stop a backfire from igniting fuel vapors in the engine compartment

A backfire flame arrestor is required on inboard gasoline engines. It contains any engine backfire so the flame cannot ignite gasoline vapors that may have collected in the engine compartment.

Source: U.S. Coast Guard / Office of the Federal Register — 46 CFR 25.35-1, Backfire flame control — https://www.ecfr.gov/current/title-46/section-25.35-1

Not the answer

  • To increase horsepower
  • To make the engine quieter
  • To cool the exhaust

Practice this

The boater safety certification exam is 50 questions and takes 40 correct — 80% — to pass. The app’s page carries a free ten-question test drawn from the same bank, marked as you go.

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