I recently bought an airplane with a YS 91 AC with Aluminum cone. I removed the cone seeing 2 nuts on the prop shaft. First nut came of easily. Now the 2nd nut wont come off. Since the prop spins freely I cannot remove the 2nd nut because there is no backplate for the nose cone like on my trainer. Do I need to use a piston stopper? I really don't want to have to use one if I can avoid it.

Please advise.

Thanks.