Rollover valve for carburetor float bowls

In a carburetor having a body, a float bowl connected to said body, a float in said body, a horizontal vent tube passage extending out of the top of the float bowl and connected to a vertical passage, the improvement comprising:

• a vertical vent tube open at both ends including a valve seat in the lower end of the tube and disposed in said vertical passage to vent said bowl to the outside atmosphere when the tube extends vertically upward;
• and
• a check valve mechanism comprising a ball disposed in the vertical passage, said mechanism being inoperative when the tube extends vertically upward, but being rendered active when the tube is tilted at an angle larger than ninety degrees with respect to the vertical allowing the ball to engage the valve seat in the lower end of the tube and seal off the tube to prevent leakage of fuel therethrough.