Hi Henry
I don't know if you receive this message as I see it's an old posting, but I read with interest your comments regarding international truck exhaust manifolds cracking, I own an international half track that has had its front section welded at some stage in its life, it seems to be holding up but I have been looking for a spare just in case it breaks again, you seem to have some knowledge of these engines and I wondered if you could tell me if the civilian engine manifolds are the same as the military manifolds fitted to the RD 450B, I see manifold come up on ebay but the casting numbers are always different and I don't have any data to check these numbers out.
I think the cracking is caused more by water dripping down from the hood joint which is directly above the manifold, I have placed a thin strip of rubber along the joint to stop this happen (I live in Europe so we get plenty of rain).
Cheers Ian