Operation of the Choke Circuit
b. Chokes are of two types; manual and automatic. The WO Carburetors described herein employs the manual type. The manual choke mechanism in the conventional carburetor consists of a valve mounted on shaft in the air horn of the carburetor, operated by an external lever attached to the shaft. Manual operated choke valves of this type usually have a semi-automatic feature which prevents over-choking after starting. This feature is accomplished by spring-loading, either all or half of the valve, or by incorporating a spring-loaded poppet device in the valve. Some models use both means to improve choke action.
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