YS Engine YSS7146 61ST-H Compatible O-ring Set  [YSS7146]

61ST-H compatible O-ring replacement

This O-ring replacement pack from YS Engine is identified as YSS7146 and refers to the 61ST-H marking. It is supplied to refurbish sealing points on compatible 61ST-H engine assemblies fitted to radio-controlled models.

Apply this set during engine servicing or rebuilds when seals are no longer sealing effectively. New O-rings prevent fuel and crankcase leaks and help retain designed internal pressures while the engine runs. Always confirm the 61ST-H stamp on your engine before ordering to ensure correct match.

Fitting the O-rings is a routine workshop task for those familiar with RC engine assembly: clean the seating grooves, lightly lubricate the new rings to prevent twisting, and carry out progressive reassembly checks. The kit supports correct maintenance procedures rather than increasing engine output on its own.