Which feature helps prevent vapor lock by routing fuel and controlling temperature?

Which feature helps prevent vapor lock by routing fuel and controlling temperature?

• A. Proper routing, anti-vapor lines, maintaining fuel temperature.
• B. Increasing fuel pump capacity without routing changes.
• C. Ventting more air into tanks.
• D. Cooling the cabin.

Answer: (C)

Vapor lock happens when fuel in the lines gets heated enough to form vapor, which blocks the pump from delivering liquid fuel to the engine. The most effective way to prevent this is to manage how the fuel is routed and keep its temperature within safe limits. Proper routing moves the fuel line away from heat sources and through cooler areas, reducing heat soak. Anti-vapor lines add a safeguard by separating the hot areas from the main feed and guiding any vapor so it doesn’t reach the pump, which helps maintain a steady supply of liquid fuel. Keeping the fuel temperature controlled—through routing choices, adequate fuel quantity, and airflow management—lowers the likelihood that fuel will vaporize in the lines. Venting more air into tanks isn’t a direct solution and can destabilize pressures, while simply increasing pump capacity without addressing the routing or temperature factors won’t prevent vapor lock.

Vapor lock happens when fuel in the lines gets heated enough to form vapor, which blocks the pump from delivering liquid fuel to the engine. The most effective way to prevent this is to manage how the fuel is routed and keep its temperature within safe limits. Proper routing moves the fuel line away from heat sources and through cooler areas, reducing heat soak. Anti-vapor lines add a safeguard by separating the hot areas from the main feed and guiding any vapor so it doesn’t reach the pump, which helps maintain a steady supply of liquid fuel. Keeping the fuel temperature controlled—through routing choices, adequate fuel quantity, and airflow management—lowers the likelihood that fuel will vaporize in the lines. Venting more air into tanks isn’t a direct solution and can destabilize pressures, while simply increasing pump capacity without addressing the routing or temperature factors won’t prevent vapor lock.