Crankshaft OS27902000 Replacement for O.S. Engine 61SX-H and 61RX-H  [OS27902000]

Service Crankshaft for 61SX-H & 61RX-H

This O.S. Engine OS27902000 crankshaft is an RC-scale replacement intended specifically for use in O.S. 61SX-H and 61RX-H nitro engines. It performs the core mechanical task of turning piston motion into rotational drive and is offered as a direct swap when the original part has worn or failed.

Compatibility is restricted to the listed model codes, so verify your engine matches 61SX-H or 61RX-H prior to purchase. Installation needs basic engine disassembly and careful attention to bearing condition and crankpin fit; fit correct bearings and check end-play and lateral runout during reassembly. When doing a full rebuild, inspect the connecting rod and crankcase mating surfaces for wear to make sure load is distributed evenly.

Balance and runout of the crankshaft directly influence vibration and throttle behaviour during tuning. After installation, carry out a static balance check and perform a cautious low-speed break-in while watching for abnormal noise or oil leakage. Proper break-in procedures and correct sealing help maintain predictable throttle response and longer service life.

Replace a worn or damaged crankshaft in 61SX-H and 61RX-H nitro engines with this unit, and follow standard rebuild checks for bearings, runout, and sealing to regain reliable operation.