Homebuilt Airplanes

Improve the fuel system of your airplane to reduce the likelihood of vapor lock by doing the following:

• Incorporate NASA vents into the vent system help provide positive pressure.
• Install fuel pumps in the fuel tanks, or as close to the fuel tank as possible. The tanks should have the maximum pressure and flow rating allowable for the carburetor.
• Replace any 90° fittings with 45° fittings or tubing with very smooth gradual bends.
• Make fittings as tight as possible to prevent air from entering the line.
• Secure lines to prevent vibration and harmonics.
• Insulate fuel lines in the engine compartment to prevent heat from soaking through to the fuel.
• Avoid locating fuel lines in close proximity to hot spots in the engine compartment.

Composite materials used for the construction of some homebuilt aircrafts may react negatively when they come in contact with fuel. The early Vari-eze homebuilt airplanes had a tendency for the spar to come apart after fuel tank leaks dribbled fuel onto the spar. You should contact the kit manufacturer to see if material used throughout your airplane is compatible with the type of fuel you will be using and to receive other recommendations.