Would 'Stop Leak' block sealer work on a Mercuiser 3.0 I4?

[lister]

IM about to put my intake manifold back on and replace all the gaskets. If I STILL get water on the oil I was thinking about using some of the stop leak block crack sealer they say works sometimes.
A friend told me that wont work on a non pressurized boat cooling system, is he right?
The goal is to maybe seal any cracks in the block (as I cant see ANY in the intake manifold other than the one on the outside)

 

[Scott Danforth]

Your friend is right. It won't work

 

[Newbie@boats]

No.

 

[thumpar]

You would need closed cooling for there to even be a chance for it to work. It will all just go out the exhaust. Most of the time it doesn't work anyway.

 

[airshot]

I just replaced mine here in early may, make sure the contact surfaces are squeaky clean and smooth, all old gasket is removed to bare metal. I ran a mill file across all the surface to be sure they were flat. Installed new gaskets and torqued to specs. NO leaks....if you do then you have other problems or the surfaces are not clean.

 

[Bondo]

If I STILL get water on the oil

Ayuh,.... I'm guessin' this motor was frozen, with water in it,.....

If so, another block is the only cure,.....