O.S. Engine OS27881330 Replacement Mixture Screw for 40E 6H-86 60G 60H 60L Carburettors  [OS27881330]

Compatibility and Safe Use

This mixture control screw is a carburettor component made to provide fine control of fuel/air mixture on compatible O.S. engine carburettors. It is intended to improve idle control and throttle transition by adjusting the carburettor mixture setting, helping modellers achieve consistent engine behavior in nitro RC applications.

Compatibility is confined to the model codes stated in the product name: 40E, 6H-86, 60G, 60H, and 60L. Do not fit the screw to carburettors that do not accept the same profile and thread form to prevent damage.

Installation and tuning notes:

• Install the screw using the OEM seating, take care to avoid cross-threading, and perform incremental adjustments while the engine runs to evaluate effect.
• If a factory baseline mixture is available, use it as a starting point, then make small fractional turns to set idle and transition.
• Keep the screw and seat clean of varnish or debris; a light application of a suitable thread-safe lubricant can help maintain smooth operation without impacting mixture readings.