Sterndrive from 4.3L mercruiser on a 3.0L Mercruiser... will it work?

[sdriggers1992]

Hi all! My boat appears to have a bad Sterndrive so I need to replace it. I have a buddy selling a boat that has the same sterndrive... Mercruiser Alpha One Gen 1. The difference is, his boat had the 4.3L inboard (blown up) while my boat has the 3.0L inboard. What kind of issues am I going to run in to if I take the Sterndrive from his boat (coming off the 4.3L motor) and put it on my boat (3.0L motor). Will the difference in the gearing cause a big issue? The only reason I am considering this is because I can get this whole boat, trailer, and replacement sterndrive I need for cheaper than I could order a used sterndrive online. Any help would be greatly appreciated!

 

[Bondo]

Ayuh,...... Welcome Aboard,...... Nope, the gear ratio is too different,.....

 

[Scott Danforth]

get the whole boat, then get a 4.3 from a u-pull-it salvage yard for $300. add some gaskets and have a 4.3 in your boat

 

[bman440440]

IMO if both are a alpha 1 gen 1 then sure... the ratio of the 3.0 should be 1:94 to 1 wile the 4.3 should be 1.81 to 1... so if you drop down 1" pitch on your prop you will be close to the same WOT RPM in the end

 

[tschmidty]

You can make it work but not ideal obviously. Prop change will help. I have one from a boat I just took the engine out of I'd sell you dirt cheap but shipping would be a pain, I am in Charlotte, NC if it matters.

 

[QBhoy]

Not ideal maybe, but you might get away with a 2” prop change.