How to Replace Fuel Lines in Boats

Will Charpentier

The fuel lines on your boat, whether copper, steel or flexible hose, carry flammable or explosive materials from the fuel tank to the engine. Because of the flexing and vibration that fuel lines on a boat experience, federal law requires a segment of flexible hose between metal lines and the tank or engine. This means that, even if you're replacing a metal fuel line, it's as simple as replacing a flexible hose.

All fuel lines terminate in a hose, held by a hose clamp.
  1. Set an open-top spill container beneath the junction between the engine or fuel tank and the fuel line you wish to remove. Shut off all fuel valves that supply fuel to the fuel line you plan to replace.

  2. Insert the blade of the screwdriver into the slot of the screw that tightens the hose clamp securing the hose to the engine or fuel tank. Turn the screw counterclockwise to loosen the screw.

  3. Allow any fuel in the fuel line to drain into the spill container. Remove the flexible hose from the motor by pulling the end of the line that you loosened away from the motor. Remove the hose clamp from the end of the fuel line after you have drained it and pulled it free.

  4. Move the spill container to the other end of the fuel line. Loosen the hose clamp and pull the line away from the motor. Remove the remaining hose clamp from the end of the fuel line.

  5. Slide the hose clamp onto the ends of the flexible hoses of the new fuel line. Push the new fuel line onto the hose fittings on the motor and tank. Tighten the hose clamp onto the hose fittings.