YS Engine YSS2021 Carburetor 56SR O-ring Replacement Seal for YS Carburetors  [YSS2021]

Replacement O-ring for YS Engine Carburetors

This O-ring is an RC carburetor seal sold as YS Engine YSS2021 and bears the 56SR marking. It functions as a service replacement for carburetor sealing surfaces to stop fuel seepage and help maintain a steady idle and consistent fuel flow during running.

The component is intended for regular maintenance and repair when the original O-ring has hardened, cracked, or lost elasticity. Fitting this seal restores sealing surfaces and reduces the chance of leaks that degrade tuning and throttle response.

Installation notes: inspect mating faces for wear or contamination before installing the O-ring, replace any damaged clamps or fittings, and seat the seal without overstretching. For tuning consistency, make sure fuel lines are clear and only adjust needle settings after confirming a leak-free installation.