Carburetor fuel shut-off system

A fuel shut-off system for a combustion engine carburetor having a body and a fuel-and-air mixing passage extended from an inlet and through the body, a fuel supply chamber carried by the body, and a fuel nozzle, the fuel supply chamber communicating with the fuel-and-air mixing passage via the fuel nozzle, the fuel shut-off system comprising:

• a valve chamber carried by the body;
• an atmosphere vent passage having an atmosphere vent seat exposed in the valve chamber;
• a vacuum bypass passage having a bypass seat exposed in the valve chamber, the vacuum bypass passage communicating between the fuel-and-air mixing passage spaced from the inlet and the valve chamber via the bypass seat;
• a fuel supply chamber passage having a fuel supply chamber port located in the valve chamber, the fuel supply chamber passage communicating between the fuel supply chamber and the valve chamber via the fuel supply chamber port;
• an actuator having an atmospheric position, a vacuum bypass position and a valve head disposed in the valve chamber;
• wherein when the actuator is in the atmospheric position the valve head is seated against the bypass seat and is un-seated from the atmosphere vent seat, and the fuel supply chamber passage is in communication with the atmosphere vent passage via the valve chamber;
• and
• wherein when the actuator is in the vacuum bypass position the valve head is seated against the atmosphere vent seat and is un-seated from the bypass seat, the vacuum bypass passage is in communication with the fuel supply through the valve passage chamber, and the atmosphere vent passage is isolated from the vacuum bypass passage and the fuel supply chamber passage.

A carburetor for a combustion engine comprising:

• a body;
• a fuel-and-air mixing passage carried by and extended through the body;
• a fuel chamber carried by the body;
• a fuel nozzle communicating between the fuel chamber and the fuel-and-air mixing passage;
• a valve chamber carried by the body;
• a fuel chamber passage communicating between the valve chamber and the fuel chamber;
• a vacuum bypass passage communicating between the valve chamber and the fuel-and-air mixing passage;
• an atmosphere passage communicating between the valve chamber and a near atmospheric pressure source;
• and
• an electrical solenoid valve having a valve head disposed operatively in the valve chamber;
• the actuator having an atmospheric position wherein the valve head obstructs the vacuum bypass passage, and a vacuum bypass position wherein the valve head obstructs the atmosphere passage.