What procedure should be followed if a reciprocating engine fire is started by backfiring and affects the induction system?

What procedure should be followed if a reciprocating engine fire is started by backfiring and affects the induction system?

• A. Continue to run the starter motor while pulling mixture to idle cutoff.
• B. Run the starter and nose the throttle to full.
• C. Immediately disconnect the battery and shut off fuel.
• D. Open the throttle and keep mixture rich.

Answer: (A)

When a fire is introduced into the induction system by a backfire, the priority is to starve the fire of fuel while still moving air through the engine to purge vapors and heat. Moving the mixture control to idle cutoff stops fuel flow, and continuing to crank with the starter forces air through the intake and cylinders, helping to blow out flames and clear remaining fuel vapor. Opening the throttle or keeping the mixture rich would add fuel and fuel-air the fire, making it worse. Disengaging the battery isn’t necessary for this immediate action and could deprive you of essential electrical systems.

When a fire is introduced into the induction system by a backfire, the priority is to starve the fire of fuel while still moving air through the engine to purge vapors and heat. Moving the mixture control to idle cutoff stops fuel flow, and continuing to crank with the starter forces air through the intake and cylinders, helping to blow out flames and clear remaining fuel vapor. Opening the throttle or keeping the mixture rich would add fuel and fuel-air the fire, making it worse. Disengaging the battery isn’t necessary for this immediate action and could deprive you of essential electrical systems.