Extension tube internal check valve

A fuel filler tube housing assembly for a vehicle fuel system, the fuel filler tube housing assembly consisting of:

• a filler tube assembly having a first mounting structure having a filler tube mounting collar including a radial mounting ring, the first mounting structure including a first hook in a first mounting configuration;
• a base over-molded about the filler tube assembly;
• a filler extension tube selectively fixed to the filler tube assembly in a second mounting configuration and having a second mounting structure including a second hook substantially similar to the first hook;
• and
• a single check valve including a pin positionable in either of the first hook and the second hook, a flapper door pivotally mountable on the pin, a seal mounted on the flapper door, and a spring positionable to bias the flapper door in one direction of pivotal movement;
• wherein the single check valve is selectively and alternatively mounted to the first mounting structure without the filler extension tube in the first mounting configuration and to the second mounting structure with the filler extension tube in the second mounting configuration, wherein in the second mounting configuration a terminal end surface of the filler extension tube is plastically welded to the radial mounting ring, wherein the filler extension tube has a length specifically configured to locate the check valve at a desired location away from the first mounting structure to accommodate a given vehicle application in the second mounting configuration.