YS Engine YSS1027S Needle Valve Set 50ST - Needle Valve Replacement for RC Model Engines  [YSS1027S]

Needle valve set for 50ST engines

This needle valve set is an RC-scale replacement part supplied under the YS Engine YSS1027S identifier and intended for use with 50ST series model glow engines. It serves as a direct replacement for worn or damaged needle components and is intended for routine tuning and maintenance tasks on remote-controlled model engines.

The assembly role is straightforward: needle valves control fuel flow to the carburettor, allowing fine adjustment of idle and mid-range mixture. When replacing the needle valve set, confirm the part number matches the engine’s service parts list and inspect surrounding seals and seats for wear before final installation.

Installation notes:

• Work on a clean bench to prevent debris entering the fuel circuit.
• Remove the carburettor cap and gently extract the old needle assembly, noting orientation and any shims or springs.
• Install the replacement needle set ensuring a proper seating and smooth travel, then perform a static fuel flow check before re-fitting the engine to the model.