Reply to heckrj:
Thanks for the response.
If I did try an epoxy, Wouldn't it penetrate deep into the crack and make it hard to grind out in the future?
You mentioned a 'cold patch'. Is that what you consider the epoxy?
Has anyone tried a product 'castaloy'? It sounds like a low temp brazing process.
Pay for metal stitching. Let a knowledgable repair tech fix it.
Castalloy is a welding rod(without GOOGLING).
You are right about welding Cast Iron, some advise is good, some isn't good. Scattered across the US are a number of talented Welders who specailize in Cast Iron engine repairs.
As far as Epoxy Patches, yes there are many fine materials available today that will work in the case of an external crack on a block. Grind it DEEP! Do not scrimp on the grind as you want virgin iron and depth of material to bond with.
Good Luck on your Decision!