None of the iron is disturbed, from what I can tell. The crack isn't even really visible with the eye. When I fill up the radiator, over time, it seeps out this side of the block. Only way I even knew it was there was from seeing the seepage occur, and the resulting water stains. I didn't think of rust through, but I guess it could be. I can't imagine that it was ever frozen, as the guy I bought it from is a neighbor, and he keeps his stuff pretty imaculate. I appreciate the opinions on this problem. I continue to fight the battle of "cheap" vs. "right".
