After I de-greased my truck's engine when I got it, I discovered a sloppy JB Weld repair on the driver side rear that had been done who knows how many years ago? It's ugly but works just fine. That's the advantage of a zero pressure cooling system.
After the JB Weld has had a chance to slightly harden, you can press a piece of course sandpaper or something into the repair to make the surface resemble cast iron. Once painted, no one will know.
