Which component prevents siphoning in the fuel system?

Which component prevents siphoning in the fuel system?

• A. Vent Line
• B. Fuel Pump
• C. Carburetor
• D. Anti-Siphon Device

Answer: (D)

Preventing siphoning in a fuel system relies on a one-way path that stops liquid from flowing back toward the tank when pressure changes could pull fuel through the line. The anti-siphon device provides that one-way action with a check valve in the fuel line, so fuel can move toward the engine during operation but cannot be drawn out of the tank if someone tries to siphon or if the line runs lower than the tank. This is why it’s the correct choice. Vent lines vent fuel tank vapors and equalize pressure; they do not stop liquid from being pulled out through a siphon. The fuel pump actively draws fuel but does not prevent reverse flow. The carburetor handles air and fuel mixing but doesn’t control siphoning either.

Preventing siphoning in a fuel system relies on a one-way path that stops liquid from flowing back toward the tank when pressure changes could pull fuel through the line. The anti-siphon device provides that one-way action with a check valve in the fuel line, so fuel can move toward the engine during operation but cannot be drawn out of the tank if someone tries to siphon or if the line runs lower than the tank. This is why it’s the correct choice. Vent lines vent fuel tank vapors and equalize pressure; they do not stop liquid from being pulled out through a siphon. The fuel pump actively draws fuel but does not prevent reverse flow. The carburetor handles air and fuel mixing but doesn’t control siphoning either.