73 starcraft old merc to new merc

[RiverNoob]

Howdy everybody.
Been a while. Was wondering how hard it would be to update this boat to a newer merc like an alpha gen 2.
What's the minimum needs to be done for that?
Can you keep old engine and change out mate, gimble,, get adapter?
Does transom have to be redone?
Etc etc.
Thanks Fer lookin

 

[alldodge]

Per Alpha to Gen 2 would to change out transom assembly, gimbal rings are different


Probably need to change out engine coupler, @Bondo and @Bt Doctur can help

 

[Bondo]

Ayuh,...... You need to replace everything from the flywheel cover, 'n aft,....
The keyhole in the transom might need some tuning, but not to much,.....

 

[RiverNoob]

Ayuh,...... You need to replace everything from the flywheel cover, 'n aft,....
The keyhole in the transom might need some tuning, but not to much,.....

What you mean by "tuning" ? Just like some minor grinding or slight enlarging or something? I wouldn't have to completely restore and re-cut a new keyhole would i?

 

[Scott06]

What you mean by "tuning" ? Just like some minor grinding or slight enlarging or something? I wouldn't have to completely restore and re-cut a new keyhole would i?

I think minor cutting of the keyhole on the top corners is required. Nothing major or to worry about. Might be for the swing of the steering arm? thread below is about it

Mercruiser engine and outdrive replacement - keyhole size

I'm looking at a 1974 boat with a Mercruiser engine and outdrive. The existing motor was run with dirt in the gas tank, and has now sat for 10 years. If I pick this up, I will want to put in a much newer (2009 or newer) Mercruiser 5.7 and Alpha One/Two or Bravo outdrive. My question is: Is...

forums.iboats.com

If you like and want to keep the boat a upgrade to the current Gen 2 is a great idea, especially if you can do the engine , transom, and drive

 

[Bondo]

What you mean by "tuning" ? Just like some minor grinding or slight enlarging or something? I wouldn't have to completely restore and re-cut a new keyhole would i?

Ayuh,.... Around the time yer's was new, the bolt holes moved abit, so you may, or may not need to redrill a couple of holes,.....
If you go with the Gen.II, there's two more holes that'll need drilling, you can use the inner plate to locate exactly where,...
The tuning I mentioned is expanding the keyhole, if the transom is Solid, no reason to fill it in, just cut out whatever is in the way,.....