US Patent 7213583 Small engine fuel tank with integrated evaporative controls

A fuel tank assembly for small engines having a vapor storage canister disposed within the tank in the vapor dome with an atmospheric vent line to the canister through the tank wall and a canister vapor outlet line also through the tank wall. A fuel vapor vent valve is disposed in the vapor dome of the tank with the vent valve outlet connected to the canister inlet. A fuel filler tube extends through the tank wall to a desired depth to prevent vapor from escaping through the filler tube when the fuel level rises to the lower end of the filler tube and alerts the operator by rapid rise of fuel in the filler tube.