120SR Cylinder Sleeve YSS3005 Replacement by YS Engine  [YSS3005]

120SR Cylinder Sleeve: Fitment and Function

This YS Engine YSS3005 cylinder liner is offered as a replacement sleeve for 120SR family RC glow engines. The copy outlines the liner's purpose during rebuilds, describing how it can recover compression and support consistent running at model scale.

The part is intended for those competent in small engine teardown and rebuild. Installation involves removing the head and checking piston and ring seating for correct dimensional fit; any pistons with marked wear or damage should be repaired or changed before fitting the new sleeve.

Fit this replacement sleeve as part of a systematic rebuild and verify clearances on the bench prior to operation to ensure steady tuning response.