Abstract: A fuel-fill adapter for use in conjunction with a manually-controlled liquid supply nozzle for filling a fuel reservoir is disclosed. The adaptor mates with liquid supply nozzle as well as the filling port of the fuel reservoir. The fuel fill adaptor includes two main fluid pathways: an incoming pathway for liquid to fill the reservoir and an outgoing pathway for vapor venting or excess liquid draining. The fuel-fill adaptor includes a low-pressure differential vacuum-breaking valve to prevent the siphon effect that would otherwise naturally occur if liquid were to enter the gas venting hose. The vacuum-breaking valve permits air to enter the adaptor, wherein the air is then drawn down the drain hose instead of any additional liquid. The vacuum breaking valve can be connected to either the incoming liquid or vent/drain pathways.

Abstract: A fuel-fill adapter for use in conjunction with a manually-controlled liquid supply nozzle for filling a fuel reservoir is disclosed. The adaptor mates with liquid supply nozzle as well as the filling port of the fuel reservoir. The fuel fill adaptor includes two main fluid pathways: an incoming pathway for liquid to fill the reservoir and an outgoing pathway for vapor venting or excess liquid draining. The fuel-fill adaptor includes a low-pressure differential vacuum-breaking valve to prevent the siphon effect that would otherwise naturally occur if liquid were to enter the gas venting hose. The vacuum-breaking valve permits air to enter the adaptor, wherein the air is then drawn down the drain hose instead of any additional liquid. The vacuum breaking valve can be connected to either the incoming liquid or vent/drain pathways.