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

Overview of the FG30 mixture valve

This replacement mixture control valve is intended for RC carburettors and is marked 70T FG30. Supplied as a single part, it is suitable for service and tuning of O.S. carburettor assemblies that accept the FG30 designation.

The valve allows direct adjustment of fuel delivery at the carburettor, letting you tune mixture richness to improve idle and low-speed behaviour. It lets technicians make incremental mixture changes without removing the whole carburettor unit.

Installation notes: follow your engine's recommended procedure—empty or isolate the fuel tank, disconnect linkages as needed, access the carburettor, and replace the mixture valve using safe working practices. Check seating and linkage alignment before conducting any test runs.

Tuning tips: perform modest adjustments and assess throttle response with the model restrained or on the bench. Note changes to engine note and idle stability, refine the setting gradually, then inspect for any fuel leaks and secure fasteners.