O.S. Engine OS27881330 Mixture Control Screw for 40E 6H-86 60G 60H 60L Carburettor Part  [OS27881330]

Mixture Control Screw Overview

This mixture control screw is an RC-scale carburettor part intended to provide fine control of fuel/air mixture on compatible O.S. engine carburettors. It serves the specific role of adjusting idling and transition behavior by changing the mixture setting at the carburettor, helping model builders and tuners dial in consistent engine response for nitro RC models.

Compatibility is limited to the model codes listed in the product name, namely 40E, 6H-86, 60G, 60H, and 60L. Use only on the matching carburettor assemblies that accept the same mixture screw profile and thread form, and avoid forcing the part into unrelated carburettors to prevent damage.

Installation and tuning notes:

• Install using the OEM seating position, turn carefully to avoid cross-threading, and make incremental adjustments while the engine is running to observe changes.
• Start from the manufacturer’s baseline mixture setting if available, then adjust in small fractions of a turn for idle and throttle transition.
• Keep the screw and seat clean from varnish or debris; a light application of appropriate thread-safe lubricant can help preserve smooth operation without affecting mixture readings.