Mixture Control Valve 70T FG30 OS4A081600 for O.S. Engine  [OS4A081600]

Service description for the mixture valve

This component is a mixture control valve for RC-scale carburettors, identified by the 70T FG30 marking and supplied as an individual service part. It is intended for maintenance, tuning, and replacement within compatible O.S. carburettor assemblies.

Functionally, the valve permits controlled adjustment of mixture richness at the carburettor. Once fitted it influences idle and low-speed throttle response, allowing tuners to refine mixtures without replacing the entire carburettor body.

Installation notes: follow safe engine maintenance procedures—remove or isolate the fuel tank, detach linkage as necessary, access the carburettor and change the mixture valve. Ensure the valve is seated correctly and linkages are aligned before initial running.

Tuning tips: alter the valve in small increments and test on the bench or with the model restrained. Monitor engine tone and idle stability, fine tune gradually, then confirm there are no fuel leaks and secure any retaining hardware.