Hi all, I need to remove & replace a 3 blade alum. prop, it is on a 1980 Mercruiser sterndrive. (This isn't a trick question, I really AM stupid...) Anyway I got the nut and star washer are off, then I thought it should just pull off the splined shaft. But there is another big collar or something there, between the prop and the washer. Do I need to pry it off with a separator? It didn't respond to more gentle persuasion. My marina manager is stumped but he noticed a very fine, straight, and almost radial split in the shaft which may be a crack...?. Any advice appreciated, can trade advice about guitars!