O.S. Engine OS29123100 Precision Cylinder Liner for 120AX Engines  [OS29123100]

Durability-Focused Cylinder Liner for 120AX

This component is the replacement cylinder liner identified by model OS29123100, designed specifically for the 120AX engine family. It acts as the internal wear surface that the piston runs against and is supplied as a single service part for engine overhaul or routine maintenance.

When inspecting a worn engine, remove the head and piston assembly to access the liner, check mating surfaces for scoring or damage, and ensure a clean fit for the replacement sleeve. Attention to cleanliness and ring face condition will help secure consistent compression after reassembly.

Although the listing does not specify liner material, the primary role of the sleeve is to restore the engine's internal geometry. Replacing a degraded liner is a standard step to recover compression and to reduce further wear during continued use and tuning.

As the direct replacement sleeve for the 120AX family, this liner is intended for maintenance and overhaul tasks; install it when wear or scoring compromises compression to bring the engine back to reliable condition.