61SX Series Crankcase Replacement OS27901000 for 61SX-H, 61SX-HG, 61SX-HGL by O.S. Engine  [OS27901000]

Replacement crankcase for 61SX engines

This crankcase is a direct RC replacement designed for use with O.S. Engine 61SX-H, 61SX-HG, and 61SX-HGL glow engines. It forms the central housing to locate the crankshaft and oil seals, restoring mechanical alignment and the integrity of the combustion chamber when the original housing is worn or damaged.

Installation is normally performed during an engine rebuild; inspect bearing seats, gasket faces, and mating surfaces carefully. The part is supplied as a single housing to replace a worn crankcase, and fitting must be verified by checking crankshaft endplay and correct seal compression prior to final assembly.

In terms of tuning and maintenance, the crankcase provides dimensional stability and sealing. It does not alter ignition or valve timing on its own but ensures the crankshaft and associated parts run true, which helps stable carburetion and ignition behavior in glow-powered RC models.

Choose this crankcase when replacing a damaged housing or carrying out a full engine rebuild to restore correct alignment and sealing within the engine assembly.