O.S. Engine OS29008219 Woodruff Key for 61,65,70,90,91 Crankshaft Part  [OS29008219]

Woodruff key for O.S. engines

This Woodruff key is an RC-scale crankshaft locating part intended for use with O.S. Engine models 61, 65, 70, 90 and 91. It serves the simple mechanical role of fitting into the crankshaft slot to lock a hub, gear, or prop driver in positive alignment, helping maintain timing and reduce axial play during operation.

Compatibility is limited to the listed O.S. Engine model sizes 61, 65, 70, 90 and 91 as named. Before installation, verify the key seats into the corresponding crankshaft keyway without forcing; mismatched keys can damage the shaft or the slot. This part is described here strictly as an RC accessory component for engine maintenance and repair.

Installation guidance (general):

• Remove the driver or gear assembly from the crankshaft following your engine's standard disassembly steps.
• Inspect the crankshaft keyway and mating part for burrs or debris and clean as required.
• Align the Woodruff key into the crankshaft slot so the curved face matches the shaft contour, then slide the driver or gear back onto the shaft, ensuring a snug fit without excessive force.
• After reassembly, check for endplay and rotation smoothness before running the engine.

Tuning and service role: the Woodruff key is a small but critical element for timing consistency and mechanical repeatability; regular inspection for wear, deformation, or surface fatigue is recommended as part of routine RC engine maintenance. Replace the key if you observe radial looseness, visible rounding of edges, or if the mating part shows movement during operation.