Dude:

Pop the backplate and hope you haven't waited too long. Dry it as well as you can, oil it up with some Dexron automatic trans fluid, (avoid WD-40 in these engines) and see if it turns smoothly. Waited too long? If it's been sitting since spring with water in it you may have ruined the bearings. But if it turns smoothly, put the backplate on, reinstall the plug, and go fly.

A point of warning: The 46 FX has a nickel plated cylinder liner, be meticulous about getting all the trash out. One small bit of grit can start the dreaded "Peeling Liner" condition. For this reason don't take any chances with the bearings. If not smooth when turning, replace them before running the engine.

Bill.