120AX Cylinder Liner Replacement - OS29123100 by O.S. Engine  [OS29123100]

Replacement Cylinder Sleeve for 120AX

This cylinder liner is an RC-scale replacement component identified by the model number OS29123100 and intended for use with the 120AX engine family. It provides the wear surface inside the engine sleeve and is supplied as a single replacement part for rebuilds or routine servicing of model engines.

For experienced model engine technicians the basic installation steps are: remove the engine head and piston assembly, withdraw the worn liner, clean and inspect the mating surfaces, then fit the new liner following standard engine reassembly practice. A careful cleaning and a close check of the piston and ring face are recommended before reassembly to preserve consistent compression and sealing.

During maintenance and tuning workflows the liner restores internal geometry that influences compression and combustion behaviour at RC scale, so replacing a scored or worn liner is a typical action when returning an engine to serviceable performance or preparing it for further tuning.

Supplied as a direct replacement for the 120AX series, this liner is intended for RC model engine maintenance and rebuilds; replace the liner when wear or scoring reduces compression to restore serviceable operation.