Abstract: Apparatus and method to prevent fuel spillage from a fuel tank vent used with a boat mounted fuel tank having a filler tube leading thereto from a fuel filler fitting mounted to a surface of the boat and a vent line leading from the fuel tank to a vent extending through the hull of the boat. A member having a hollow interior and a removable closure member is mounted substantially flush with a surface of the boat and in close proximity to the fuel filler fitting. The member has a fitting in the interior thereof which is connected to a first section of vent tube leading from the fuel tank. The interior of the member is also connected to a second section of vent tube that leads to the vent extending through the hull of the boat. When the closure is on the member, the interior of the fuel tank is in communication with the vent. When the boat is to be fueled, the cap is removed from the member and a fuel overflow container is connected to the fitting.