Re: '83 bayliner capri aq125a
Understand, they are not freeze plugs, they are core plugs. Used in the casting process as a way to hold the cores of the mold in place and also makes a nice place to clean the sand out of the casting. That is all they were ever designed for.
If one or more core plugs are pushed out, you may also have a cracked manifold. Possibly internally where you can't see it.