STATER FOR CARBURETOR

PURPOSE:To enable the smooth start by installing a starting fuel passage which is branched from a fuel passage and a starting air passage and carrying out all injection of fuel in the initial stage and then carrying out idling and then cutting off the fuel injection, while jetting air only in the intermediate stage, in a carburetor. CONSTITUTION:A starting fuel passage 31A is branched from a fuel passage 8A on the discharge side, and connected to a pressure chamber 30 and opened into an air feeding passage 2 for a carburetor through an opening/closing valve 32. A starting air passage 37 is formed, and the outside air is allowed to flow into the air feeding passage 2 through an air control valve 36 which is formed integrally with the opening/ closing valve 32. Since, in the initial stage of the starting operation, the pressure of a portion of the fuel which is introduced into the pressure chamber 30 is low, the opening/closing valve 32 is in opened state, and fuel is jetted into the air feeding passage 2, while the air control valve is in closed state and air is not jetted. The fuel pressure increases, together with the increase of the revolution, and fuel is throttled by the opening/closing valve 32, and since the control valve 36 is opened, air is jetted into the air feeding passage, and the mixed gas is diluted. After the completion of warming, fuel and air are cut off. Therefore, the smooth start is enabled.