YS Engine YSS3019S Carburetor Assembly for 120SR Engines  [YSS3019S]

Carburetor role and fit

This is an RC-scale carburetor assembly supplied under the YS Engine part number YSS3019S and intended for use with the 120SR family as indicated in the product name. It serves as a direct replacement component to restore fuel metering and idle control on compatible model engines, not for full engines or non-RC use.

The assembly is presented as a serviceable spare: it locates to the engine intake flange, interfaces with the throttle arm and throttle linkage, and accepts standard needle adjustments used for mixture tuning. When replacing the unit, check flange alignment, gaskets or O-rings, and throttle travel to avoid binding or air leaks.

For tuning, use the carburetor to set idle mixture and main-jet response following established RC engine tuning practices: small incremental needle turns, controlled run-in on a stand or in a safe field, and verification under load. This description focuses on fit and function rather than step-by-step instructions.

As a spare part for RC-scale engines, the YS Engine YSS3019S carburetor assembly is intended to restore factory-style fuel control and provide a predictable platform for needle-based tuning; verify fit and sealing before operation.