Carburetor Rotor 40L 55Hz Upgrade for O.S. Engine OS25881200  [OS25881200]

Service rotor for RC glow carburettors

This O.S. Engine OS25881200 carburetor rotor fits carburettor assemblies designed for a 40L rotor labelled 55Hz and acts as the rotating metering component inside the carburettor barrel. It plays a key role in modulating air and fuel flow across throttle ranges.

As a direct replacement part, the rotor is suitable for routine maintenance to recover consistent throttle response when the original has worn or collected deposits. Its dimensions match small-model glow engine carburettors that use removable 40L rotors with the 55Hz mark.

Installation advice: replace the existing rotor and ensure the new unit spins freely without interference; secure any clips or screws appropriately. After installation, review idle and adjust the low and high needles to re-establish the correct mixture and smooth running.

Tuning effect: the rotor's fit and surface quality impact throttle transition and idle steadiness. A correctly fitted rotor makes needle adjustments more repeatable and throttle behaviour easier to predict during running and tuning sessions.