Rotor Stop Set Screw for 40R,45R,FS,FT - O.S. Engine OS22681306  [OS22681306]

Functional role of the rotor stop set screw

The rotor stop set screw from O.S. Engine is a compact replacement designed for model glow engine maintenance and tuning sessions. It provides the mechanical stop that keeps rotor positioning fixed on the engine models named in the product title, aiding consistent rotor indexing for tuning work.

Compatibility applies only to the engine codes listed in the product name: 40R, 45R, FS, FT. Do not assume cross-compatibility without verification from the engine documentation.

Fitting notes: extract the old rotor stop, inspect thread condition and seating, install the new set screw and tighten cautiously to avoid striping threads. Confirm rotor position after installation and run a brief check to ensure stable operation.

Tuning impact: as a maintenance part, it helps preserve rotor alignment which can improve repeatability during bench setups and field tuning, reducing variation between runs.