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A fill limit vent valve assembly includes a cover assembly, a valve assembly and a fill control system. The fill control system has a primary fuel control window, a secondary fuel control window, a first conduit and a second conduit, the primary and secondary fuel control windows in respective commu

A fill limit vent valve assembly includes a cover assembly, a valve assembly and a fill control system. The fill control system has a primary fuel control window, a secondary fuel control window, a first conduit and a second conduit, the primary and secondary fuel control windows in respective communication with the first and second conduits, the first conduit extending a first distance along the housing and terminating in a first vent aperture, the second conduit extending a second distance along the housing and terminating in a second vent aperture spaced apart from the first vent aperture, the primary fuel control window and the first vent aperture configured to facilitate fuel filling shut-off in a first fuel condition, the secondary fuel control window configured to shut-off fuel filling in a second fuel condition, the second vent aperture configured to provide a fixed amount of fuel vapor venting from the float chamber between the first and second fuel conditions to control entry of a set quantity of a liquid fuel into the fuel tank after the first fuel condition and before the second fuel condition.

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That which is claimed is: 1. A fill limit vent valve assembly configured for attachment to a fuel tank wall and having a cover assembly with a nozzle configured for connection to a vapor recovery device for a fuel tank, the fill limit vent valve assembly comprising: a valve assembly having a housin

That which is claimed is: 1. A fill limit vent valve assembly configured for attachment to a fuel tank wall and having a cover assembly with a nozzle configured for connection to a vapor recovery device for a fuel tank, the fill limit vent valve assembly comprising: a valve assembly having a housing connectable to the cover assembly in vapor communication with the nozzle; and a fill control system defining at least one window in communication with at least one conduit disposed proximate the housing, the conduit terminating in a vent aperture in the housing, the window and the vent aperture configured for directing a liquid fuel into the housing to limit turbulence therein to prevent liquid fuel carry-over to the vapor recovery device. 2. The fill limit vent valve assembly as in claim 1, wherein the window defines an upper edge configured to shut-off fuel filling in a first fuel condition when the rising liquid fuel reaches proximate the upper edge. 3. The fill limit vent valve assembly as in claim 2, wherein the upper edge diverges from horizontal such that the rising liquid fuel closes the window in gradations to gradually build up pressure in the fuel tank to cause the liquid fuel to rise in the conduit and enter the housing in a controlled manner. 4. The fill limit vent valve assembly as in claim 2, further comprising a secondary fuel control window defining a top edge configured to shut-off fuel filling in a second fuel condition when the rising liquid fuel reaches proximate the top edge. 5. The fill limit vent valve assembly as in claim 4, wherein the second fuel condition results when the liquid fuel obstructs the top edge of the secondary fuel control window such that fuel vapor venting from the housing via the secondary fuel control window is at least temporarily blocked to cause vapor pressure in the fuel tank to back up the liquid fuel in a fill nozzle and trigger a fill-limit sensor to at least temporarily stop fuel filling. 6. The fill limit vent valve assembly as in claim 5, further comprising a pinhole in the housing defined above a maximum fluid level in the housing, the pinhole configured to equalize a differential pressure between the housing and the fuel tank after the second fuel condition to permit a float valve of the valve assembly to move in an axial direction away from the vapor-inlet opening. 7. The fill limit vent valve assembly as in claim 1, wherein the at least one window is a primary fuel control window and further comprising a secondary fill slot spaced apart from the primary fuel control window, the primary fuel control window and the secondary fill slot configured to control an initial fuel filling condition, an interim fuel filling condition, and a final fuel filling shut-off condition. 8. A fill limit vent valve assembly at least partially disposed within an interior of a fuel tank and configured for connection to a vapor recovery device, the fill limit vent valve assembly comprising: a cover assembly having a nozzle and a mounting portion, the nozzle in communication with the vapor recovery device and defining a vapor-inlet opening, a vapor-outlet opening and a passageway therebetween, the mounting portion configured for attachment to a fuel tank wall; and a valve assembly attachable to the cover assembly in vapor communication with the nozzle, the valve assembly including a housing, a float valve, and a fill control system, the housing defining a base and a float chamber therein, the float valve operably disposed within the float chamber and cooperable with the fill control system to seal the vapor-inlet opening of the nozzle, wherein the fill control system defines a primary fuel control window, a secondary fuel control window, a first conduit and a second conduit, the primary and secondary fuel control windows in respective communication with the first and second conduits, the first conduit extending a first distance along the housing and terminating in a first vent aperture, the second conduit extending a second distance along the housing and terminating in a second vent aperture spaced apart from the first vent aperture, the primary fuel control window and the first vent aperture configured to facilitate fuel filling shut-off in a first fuel condition, the secondary fuel control window configured to shut-off fuel filling in a second fuel condition, the second vent aperture configured to provide a fixed amount of fuel vapor venting from the float chamber between the first and second fuel conditions to control entry of a set quantity of a liquid fuel into the fuel tank after the first fuel condition and before the second fuel condition. 9. The fill limit vent valve assembly as in claim 8, wherein the base is configured to direct the liquid fuel when rising in the fuel tank into the primary fuel control window. 10. The fill limit vent valve assembly as in claim 8, wherein the base defines a hole therethrough, the hole configured for liquid fuel drainage from the float chamber. 11. The fill limit vent valve assembly as in claim 8, wherein the primary fuel control window defines an upper edge configured to shut-off fuel filling in the first fuel condition when the rising liquid fuel reaches proximate the upper edge. 12. The fill limit vent valve assembly as in claim 11, wherein the first fuel condition occurs when the liquid fuel rises proximate the upper edge and vapor pressure in the fuel tank causes the liquid fuel to enter the first conduit and enter the float chamber via the first vent aperture such that the float valve is buoyed by the liquid fuel in the float chamber to seal the vapor-inlet opening. 13. The fill limit vent valve assembly as in claim 12, wherein the upper edge diverges from horizontal such that the rising liquid fuel closes the primary fuel control window in gradations to gradually build up pressure in the fuel tank to cause the liquid fuel to rise in the first conduit and enter the float chamber in a controlled manner. 14. The fill limit vent valve assembly as in claim 11, wherein the upper edge diverges relative to the base such that a cross-section of the rising liquid fuel is sized to control a flow rate of the liquid fuel into the first conduit. 15. The fill limit vent valve assembly as in claim 8, wherein the secondary fuel control window defines a top edge configured to shut-off fuel filling in the second fuel condition when the rising liquid fuel reaches proximate the top edge. 16. The fill limit vent valve assembly as in claim 15, wherein the second fuel condition results when the liquid fuel obstructs the top edge of the secondary fuel control window such that fuel vapor venting from the float chamber via the second conduit and the second vent aperture is at least temporarily blocked to cause vapor pressure in the fuel tank to back up the liquid fuel in a fill nozzle and trigger a fill-limit sensor to at least temporarily stop fuel filling. 17. The fill limit vent valve assembly as in claim 8, wherein the first and second conduits are configured to communicate a liquid, a vapor, and combinations thereof to one of the float chamber or to the interior of the fuel tank. 18. The fill limit vent valve assembly as in claim 8, wherein the fill control system is disposed in a direction of the fuel tank wall to reduce exposure to liquid fuel splash in the fuel tank. 19. The fill limit vent valve assembly as in claim 8, wherein the first conduit defines at least two passageways in communication with the float chamber. 20. The fill limit vent valve assembly as in claim 19, wherein the at least two passageways are in liquid communication with the float chamber. 21. The fill limit vent valve assembly as in claim 8, wherein the second conduit defines at least two passageways in communication with the float chamber. 22. The fill limit vent valve assembly as in claim 21, wherein the at least two passageways are in vapor communication with the float chamber. 23. The fill limit vent valve assembly as in claim 8, wherein the first vent aperture is configured to deliver the liquid fuel from the first conduit into the float chamber. 24. The fill limit vent valve assembly as in claim 23, wherein the first vent aperture opens proximate an inner wall of the float chamber such that entry of the liquid fuel from the first conduit into the float chamber is directed away from the vapor-inlet opening and the float valve to reduce turbulence in the housing. 25. The fill limit vent valve assembly as in claim 8, wherein the second distance is greater than the first distance such that the second vent aperture is spaced closer to the vapor-inlet opening than the first vent aperture. 26. The fill limit vent valve assembly as in claim 8, wherein the second vent aperture is arranged at least above a maximum fluid level in the float chamber to control the liquid fuel from entering the second vent aperture. 27. The fill limit vent valve assembly as in claim 26, wherein the maximum fluid level in the float chamber is defined by a maximum axial movement of the float valve in a direction of the vapor-inlet opening. 28. The fill limit vent valve assembly as in claim 8, wherein the first vent aperture is arranged above a maximum fuel level in the float chamber to prevent turbulence from unsealing the float valve in a static condition. 29. The fill limit vent valve assembly as in claim 28, wherein a temperature increase in the static condition causes the fuel tank to expand and allows the liquid fuel to rise into the first conduit. 30. The fill limit vent valve assembly as in claim 29, wherein the vapor-inlet opening remains sealed by the float valve such that a pressure relief valve is operable to relieve pressure in the fuel tank to prevent liquid fuel carry-over to the vapor recovery device. 31. The fill limit vent valve assembly as in claim 8, wherein a rate of pressure equalization between the float chamber and the fuel tank after the first fuel condition is a function of a diameter of the second vent aperture. 32. The fill limit vent valve assembly as in claim 31, wherein a period of time between at least two trickle fills is a function of the diameter of the second vent aperture. 33. The fill limit vent valve assembly as in claim 31, wherein the diameter of the second vent aperture is from about 2.0 mm to about 3.0 mm. 34. The fill limit vent valve assembly as in claim 8, further comprising a pinhole in the housing defined above a maximum fluid level in the float chamber, the pinhole configured to equalize a differential pressure in the float chamber with a pressure in the fuel tank after the second fuel condition to permit the float valve to move in an axial direction away from the vapor-inlet opening. 35. The fill limit vent valve assembly as in claim 8, wherein the float valve is configured to releasably seal the vapor-inlet opening of the nozzle during one of the first fuel condition, the second fuel condition, or intermittently therebetween. 36. A fill limit vent valve assembly at least partly disposed in an interior of a fuel tank, the fill limit vent valve assembly comprising: a cover assembly having a nozzle and a mounting portion, the nozzle defining a vapor-inlet opening, a vapor-outlet opening and a passageway therebetween, the nozzle configured for connection to a vapor recovery device, the mounting portion configured for attachment to a fuel tank wall; and a valve assembly connectable to the cover assembly in vapor communication with the nozzle, the valve assembly including a housing, a float valve, and a fill control system, the housing defining a base and a float chamber therein, the base configured to direct a rising liquid fuel from the fuel tank into the primary fuel control window, the float valve operably disposed within the float chamber and cooperable with the fill control system to seal the vapor-inlet opening of the nozzle, the fill control system defining a primary fuel control window, a secondary fuel control window, a first conduit and a second conduit, the primary and secondary fuel control windows in respective communication with the first and second conduits, the first conduit extending a first distance along the housing and terminating in a first vent aperture opening proximate an inner wall of the float chamber, the second conduit extending a second distance along the housing and terminating in a second vent aperture spaced apart from the first vent aperture, the primary fuel control window and the first vent aperture configured to control entry of the liquid fuel from the first conduit into the float chamber to reduce turbulence in the housing and to shut-off fuel filling in a first fuel condition, the secondary fuel control window configured to shut-off fuel filling in a second fuel condition, the second vent aperture configured to provide a fixed amount of fuel vapor venting from the float chamber between the first and second fuel conditions to control entry into the fuel tank of a set quantity of the liquid fuel after the first fuel condition and prior to the second fuel condition. 37. The fill limit vent valve assembly as in claim 36, wherein the base defines a hole therethrough, the hole configured for liquid fuel drainage from the float chamber. 38. The fill limit vent valve assembly as in claim 36, wherein the primary fuel control window defines an upper edge configured to shut-off fuel filling in the first fuel condition when the rising liquid fuel reaches proximate the upper edge. 39. The fill limit vent valve assembly as in claim 38, wherein the first fuel condition occurs when the liquid fuel rises proximate the upper edge and vapor pressure in the fuel tank causes the liquid fuel to enter the first conduit and enter the float chamber via the first vent aperture such that the float valve is buoyed by the liquid fuel in the float chamber to seal the vapor-inlet opening. 40. The fill limit vent valve assembly as in claim 39, wherein the upper edge diverges from horizontal such that the rising liquid fuel closes the primary fuel control window in gradations to gradually build up pressure in the fuel tank to cause the liquid fuel to rise in the first conduit and enter the float chamber in a controlled manner. 41. The fill limit vent valve assembly as in claim 39, wherein the upper edge diverges relative to the base such that a cross-section of the rising liquid fuel is sized to control a flow rate of the liquid fuel into the first conduit. 42. The fill limit vent valve assembly as in claim 36, wherein the secondary fuel control window defines a top edge configured to shut-off fuel filling in the second fuel condition when the rising liquid fuel reaches proximate the top edge. 43. The fill limit vent valve assembly as in claim 42, wherein the second fuel condition results when the liquid fuel obstructs the top edge of the secondary fuel control window such that fuel vapor venting from the float chamber via the second conduit and the second vent aperture is at least temporarily blocked to cause vapor pressure in the fuel tank to back up the liquid fuel in a fill nozzle and trigger a fill-limit sensor to at least temporarily stop fuel filling. 44. The fill limit vent valve assembly as in claim 36, wherein the first and second conduits are configured to communicate a liquid, a vapor, and combinations thereof to one of the float chamber or to the interior of the fuel tank. 45. The fill limit vent valve assembly as in claim 36, wherein the first conduit defines at least two passageways in communication with the float chamber. 46. The fill limit vent valve assembly as in claim 45, wherein the at least two passageways are in liquid communication with the float chamber. 47. The fill limit vent valve assembly as in claim 36, wherein the second conduit defines at least two passageways in communication with the float chamber. 48. The fill limit vent valve assembly as in claim 47, wherein the at least two passageways are in vapor communication with the float chamber. 49. The fill limit vent valve assembly as in claim 36, wherein the first vent aperture is configured to deliver the liquid fuel from the first conduit into the float chamber. 50. The fill limit vent valve assembly as in claim 49, wherein the first vent aperture opens proximate an inner wall of the float chamber such that entry of the liquid fuel from the first conduit into the float chamber is directed away from the vapor-inlet opening and the float valve to reduce turbulence in the housing. 51. The fill limit vent valve assembly as in claim 36, wherein the second distance is greater than the first distance such that the second vent aperture is spaced closer to the vapor-inlet opening than the first vent aperture. 52. The fill limit vent valve assembly as in claim 36, wherein the first vent aperture is arranged above a maximum axial movement of the float valve in a direction of the vapor-inlet opening. 53. The fill limit vent valve assembly as in claim 38, wherein a fuel-vapor mix is contained in the first conduit and above a maximum fuel level in the float chamber such that the float valve remains sealed proximate the vapor-inlet opening in a static condition. 54. The fill limit vent valve assembly as in claim 36, wherein a rate of pressure equalization between the float chamber and the fuel tank during the first fuel condition is a function of a diameter of the second vent aperture. 55. The fill limit vent valve assembly as in claim 54, wherein a period of time between at least two trickle fills is a function of the diameter of the second vent aperture. 56. The fill limit vent valve assembly as in claim 36, further comprising a pinhole in the housing defined above a maximum fluid level in the float chamber, the pinhole configured to equalize a differential pressure in the float chamber with a pressure in the fuel tank after the second fuel condition to permit the float valve to move in an axial direction away from the vapor-inlet opening. 57. A fill limit vent valve assembly for attachment to a fuel tank wall, the fill limit vent valve assembly comprising: a cover assembly having a nozzle defining a vapor-inlet opening, a vapor-outlet opening and a passageway therebetween; and a valve assembly connectable to the cover assembly in vapor communication with the nozzle, the valve assembly including a housing and a float valve, the housing defining a base and a float chamber therein, the base configured to direct a rising liquid fuel from the fuel tank through the primary fuel control window; and a fill control system defining a primary fuel control window, a secondary fuel control window, a first conduit and a second conduit, the primary and secondary fuel control windows in respective communication with the first and second conduits, the first conduit terminating in a first vent aperture opening into the float chamber, the second conduit terminating in a second vent aperture opening into the float chamber, the primary fuel control window and the first vent aperture configured to control entry of the liquid fuel from the first conduit into the float chamber to facilitate sealing of the vapor-inlet opening by the float valve in a first fuel condition, the secondary fuel control window configured to shut-off fuel filling in a second fuel condition, the second vent aperture configured to provide a fixed amount of fuel vapor venting from the float chamber to control entry of a set quantity of the liquid fuel before the second fuel condition. 58. The fill limit vent valve assembly as in claim 57, wherein the base defines a hole therethrough, the hole configured for liquid fuel drainage from the float chamber. 59. The fill limit vent valve assembly as in claim 57, wherein the primary fuel control window defines an upper edge configured to shut-off fuel filling in the first fuel condition when the rising liquid fuel reaches proximate the upper edge. 60. The fill limit vent valve assembly as in claim 59, wherein the first fuel condition occurs when the liquid fuel rises proximate the upper edge and vapor pressure in the fuel tank causes the liquid fuel to enter the first conduit and enter the float chamber via the first vent aperture such that the float valve is buoyed by the liquid fuel in the float chamber to seal the vapor-inlet opening. 61. The fill limit vent valve assembly as in claim 59, wherein the secondary fuel control window defines a top edge configured to shut-off fuel filling in the second fuel condition when the rising liquid fuel reaches proximate the top edge. 62. The fill limit vent valve assembly as in claim 61, wherein the second fuel condition results when the liquid fuel obstructs the top edge of the secondary fuel control window such that fuel vapor venting from the float chamber via the second conduit and the second vent aperture is at least temporarily blocked to cause vapor pressure in the fuel tank to back up the liquid fuel in a fill nozzle and trigger a fill-limit sensor to at least temporarily stop fuel filling. 63. The fill limit vent valve assembly as in claim 57, wherein the first conduit defines at least two passageways in liquid communication with the float chamber. 64. The fill limit vent valve assembly as in claim 57, wherein the second conduit defines at least two passageways in vapor communication with the float chamber. 65. The fill limit vent valve assembly as in claim 57, wherein the first vent aperture is configured to deliver the liquid fuel from the first conduit into the float chamber. 66. The fill limit vent valve assembly as in claim 65, wherein the first vent aperture opens proximate an inner wall of the float chamber such that entry of the liquid fuel from the first conduit into the float chamber is directed away from the vapor-inlet opening and the float valve to reduce turbulence in the housing. 67. The fill limit vent valve assembly as in claim 57, wherein a period of time between at least two trickle fills is a function of a diameter of the second vent aperture. 68. The fill limit vent valve assembly as in claim 57, further comprising a pinhole in the housing defined above a maximum fluid level in the float chamber, the pinhole configured to equalize a differential pressure between the float chamber and the fuel tank after the second fuel condition to permit the float valve to move in an axial direction away from the vapor-inlet opening.