Patent ID: 8746479

Claim:
A method of sealing a fuel filler neck assembly, comprising: installing an anti-siphon sleeve inside a fuel filler neck so that a flange of said anti-siphon sleeve is seated on a rim of said fuel filler neck; securing a base within said anti-siphon sleeve by seating an annular shoulder of said anti-siphon sleeve in an annular groove of said base, said base having an opening for the passage of fuel and a circular segment base with a recessed portion; providing an O-ring around said opening; securing a biasing structure to said recessed portion; pivotally attaching a hinged closure to said recessed portion, said hinged closure movable between: a closed position wherein said hinged closure is biased into sealing engagement with said O-ring to seal said opening and prevent fuel from escaping; and, an open position wherein said hinged closure is moved by a fuel pump nozzle to unseal said opening and allow fuel to flow through said opening.