ok on my mercruiser pre alpha outdrive it has what i think is a merc prop, but i can't figure out the size and pitch of the prop. All the numbers i can find on it don't seem to help either. here are the numbers : on side of prom it has MM 4771 on the hub it has the following numbers one i think a Part number 48-36016 also it has these numbers 994B, and B1881, i measured the prop and i seems the diameter is aprox 14.5 inches. thanks for your help on this matter<br />Shane