HI lets start with the basics. I just picked up 1973 hurricane fun deck, with a 188 hp mercruiser (302 ford 2bbl). Pre alpha 888 stern drive.The one with big eye hook loop on top. engine #3601224 stern drive #3607063. I was working on the cooling system ( thred, cooling raw water???) when I found some thing wedged in the prop between prop and prop hub. It was slightly rubbing on the tab washer and cover nut (64 65) for bearing carrier. To the point, what is this part or is it even part of the boat? the part is a half circle plate. two metal plates with rubber in between and rubber on both outter sides. I have looked over several diagrams for stern drives and can't find anything that looks close. Thanks for the help:noidea: