Could be wrong about that, but my experience (using JB Weld) is it doesn't stick very well and ends up causing more problems down the road.
Don't under estimate the usefulness of JB weld in this kind of situation. The trick is to get the area perfectly clean before applying.
My experience with JB and outboard repairs. Salt had eaten into the block pretty badly in the area of the head gaskets. Couldn't keep a head gasket on the motor for more than a couple of outings.
Out of desperation, I cleaned the head surfaces thoroughly with lacquer thinner and a brass toothbrush. Blew everything off and cleaned it again. Skimmed the entire surface with JB using a putty knife. Let it dry over night and skimmed everything again. This time I covered the area with plastic wrap and let it setup a bit. Removed the plastic wrap and had a perfectly smooth surface to work with. A bit of work with heavy duty flat files of varying roughness and the job was complete.
I put another 75 hours on the motor before I repowered. As far as I know, that motor is still in still in use today