exhaust manifold question on a 4cyl yj

[4wheelinmike]

I notticed what looks like a crack on my manifold. I'm going to take it off today and if I find it is a crack can I weld it? Is the manifold cast iron? If it is cast iron do I heat it up first then weld it with low heat? I've never welded cast iron before

[6spdYJ]

Cast can be welded, sounds like you've got the right idea. The trick is controlling the cooling rate. Yhere are some very good video tutorials online. Comparing time to study, prep, try, have it crack again etc... Most would opt for a replacement manifold.