Genuine OS factory piston ring for the FS-56α (FS-56A) four-stroke glow engine. A fresh ring is the standard fix for an FS-56α that's lost compression through normal wear — restoring pinch, easier starting, and consistent idle — and should always be fitted when the piston is renewed.

This is the ring for piston 44603200 (sold separately, ring not included with the piston). While the engine is stripped, inspect the cylinder liner bore — scoring or wear ridges mean the liner (44603100, also available separately) should be replaced too, as a new ring can't seal against a worn bore.

Fit the ring with care — ease it over the piston without over-spreading and check its seating in the groove before reassembly. Refit with a new head gasket, then run the engine in gently on a rich setting for the first tanks to bed the ring against the liner.

Specifications

Brand: OS Engines (Japan)
Part number: 44603400
Type: Piston ring
Suits: OS FS-56α (FS-56A) four-stroke
Fits piston: 44603200