Hey guys I am going to be buying a new or used lower unit for my boat. It has a Pre-alpha outdrive on it right now. Can anyone tell me what Mercruiser Lower units will fit on this outdrive. Thanks
Actually depends on the exact year .Very early ones used a 8 spline driveshaft (NLA) .those parts are not available. Late units had 12-13? same as the Alpha type. IF you have the later type driveshaft then any lower unit from Series`1, R,MR,Alpha I will interchange.
If you have the 8, then complete drive replacement is another option.Make sure you have the correct gear ratio and input shaft length (8-9 inch)
Alpha GEN II`s will not interchange
i am also looking to replace my lower unit on my 77 invader. its a MR drive i believe. Looking to swap a alpha unit from a guy who's selling it on craigslist. I should be good right? is 400 high or average for a used drive? other than gears shifting, and no leaks what else should i look for. Thanks for the help!
