re: welding the block, there are two schools of thought on welding cast iron. In both cases, you would use a nickel rod. There are several different versions of a nickel rod with slightly different characteristics. One is better for machining after the weld, for example. The crack must also be accessible enough that you could grind the edges down to make a nice V for the welding. One school of thought says preheat the casting thoroughly, perform the weld, then pack the casting in sand so that it will cool very slowly. The other way is to work on the casting cold, but to make a lot of very short beads (no more than an inch at a time), and wait between beads to give the heat time to dissipate through the casting. I've done some cast welding, and I've used the second approach, mostly because I don't have an oven for preheating. So far, it's worked out for me. I will add, however, that I haven't tried it on a block, and if the crack is between the cyclinders as others have said, I don't think I'd try -- just too hard to get clean access to the weld area. The mixed up stuff referred to in an earlier post is JBWeld -- sort of an epoxy for metal. It's great stuff. Good luck, - David
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