Abstract: A refueling device that when mounted to a marine fuel tank facilitates refueling and minimizes the propensity for both spit-back and well back while simultaneously allowing a free flowing open pathway through which vapors generated by the refueling event may pass unencumbered.

Abstract: A fuel system 10 includes a fuel tank 11, a demand valve 12, a primer pump 13, and an internal combustion engine 14. The demand valve 12 closes and prevents fuel flow to the engine and potential fuel spillage when the engine is not running, even if a positive pressure condition exists in the fuel tank 11. The demand valve 12 is opened to allow fuel flow to the engine 14 only when the engine is to be started or is running. This opening of the demand valve is caused by a vacuum in a central cavity 31 of the demand valve 12. The vacuum causes a diaphragm 43 to move laterally and act through a connector 44 against a pin 39 connected to a valve member 37, to tilt or rotate the valve member 37 relative to a valve seat 34.