FS70U and GT22 Crankshaft Ball Bearing - OS44731000 by O.S. Engine  [OS44731000]

Replacement Crankshaft Bearing for FS70U and GT22

This O.S. Engine crankshaft ball bearing is an RC-scale replacement part specified by the listed model code OS44731000. It is intended for use with FS70U and GT22 engine model references found in the original product name, and serves the role of supporting the crankshaft end play and rotation inside nitro model engines.

Use this bearing as a like-for-like service part when the original crankshaft bearing shows wear, rough rotation, or excessive play. When replacing, verify the bearing seat and crankshaft journal for burrs or corrosion, clean mating surfaces, and confirm a press-fit or slip-fit tolerance before final assembly. This description avoids giving step-by-step repair procedures but highlights fit and inspection points relevant to model engine work.

In tuning and maintenance context, a properly seated crankshaft ball bearing contributes to smoother idle and consistent high-rpm response in nitro RC setups by reducing unwanted shaft movement and friction losses. Choose appropriate lubrication and follow your engine’s manufacturer guidance for service intervals and break-in considerations.