61ST-H Compatible Regulator Valve YS Engine YSS7137  [YSS7137]

Product Snapshot: Regulator Valve for 61ST-H

This regulator valve is listed as YS Engine YSS7137 and is intended as a direct spare for the 61ST-H regulator valve assembly. The outline below covers what the component does in an RC engine, where it belongs in scheduled maintenance, and items to check during fitting and tuning.

Functionally, the part helps regulate fuel pressure and flow in small glow/nitro RC engines, contributing to a stable idle and consistent throttle response when the carburetion and fuel delivery are otherwise correct. Use it as a replacement during rebuilds or when troubleshooting unstable engine behaviour.

Fitment notes: ensure the part code matches the removed valve, keep the work area clean to prevent fuel circuit contamination, and tighten fittings by hand following suggested torque guidance. After installation, perform a run-up and adjust idle to confirm steady pressure and reliable throttle response.

Role in tuning: the regulator valve interacts with needle settings and carb adjustments; coordinate those changes after replacing the valve. Replace any worn O-rings or seals at the same time to maintain proper pressure control.