Re: Merc Alpha 1 3.0 Engine Block Crack - Picture.
I'm not suprised at all. They tend to crack externally as opposed to V motors that tend to crack internally. There is an excellent product called Marine Tex. That's the best epoxy repair I've come accross, although there are others that work okay too. The key is surface prep. It should be rough sanded or ground clean, epoxied, then painted. It can last many years. Eventually it'll start leaking again. So just grind it off and redo for several more years.

<br /><br />I am uncomfortable about the sale however. I don't know who screwed-up, but somebody did. Maybe they sold it for that reason. I hate when people pull that!

Looks like somebody goobered-up a mess for you to clean up. Make sure you have solid clean metal to epoxy to. No lime, no paint, no rust. You might have to remove the manifold to get at it decent.