Replacement Carburettor Rotor OS42581200 by O.S. Engine for RC Engines 70R Fsa-155-P  [OS42581200]

Overview: carburettor rotor function

This component from O.S. Engine is the rotating metering element inside the carburettor slide that helps manage airflow and throttle response. It is supplied as a spare part for maintenance and to restore accurate throttle behaviour in nitro-powered RC models.

Fitment involves removing the carburettor, recording rotor orientation, examining the slide and seal surfaces, installing the rotor carefully on its shaft, and confirming smooth, full-range movement. Keep assembly forces low and retain any undamaged seals for reuse where appropriate.

Although the rotor does not change fuel composition, its condition can materially affect idle control and throttle progression; include the rotor when tracing uneven idle or delayed throttle reaction. Clean with suitable non-abrasive agents to preserve precise fitment.