O.S. Engine OS25081202 Adjustable Airbleed Screw for 35RC 40SP 40P 50 Engines  [OS25081202]

Precision airbleed screw for nitro RC carburettors

This airbleed screw is an RC carburettor component made to fit O.S. Engine models 35RC, 40SP, 40P and 50. It gives a serviceable bleed point for low-speed mixture tuning without changing the main needle assembly, allowing finer control of idle and initial throttle response while dialing in track or field setups.

Compatibility is restricted to the engine model codes listed above. The part is supplied as a direct-replacement service item for nitro RC carburettor airbleed ports; confirm fitment by comparing the existing airbleed screw geometry on your carburettor before fitting.

Installation is straightforward for hobbyists familiar with carburettors. Remove the top or access cap as required, back out the original airbleed screw and carefully thread in the replacement until it seats. Make only small adjustments and test idle and throttle response between changes; the airbleed mainly affects low-throttle mixture rather than full-throttle settings.

Routine care: keep the screw and threads free of fuel residue, check for wear or damage, and replace if the seating surface or threads are compromised. Store spare components cleanly to avoid contamination that could impair carburettor performance.