Is cast iron weldable?

[Jon K]

I am looking at picking up a cast iron turbo manifold but its not flanged for an external wastegate - is cast iron weldable?

[Blitzkrieg Bob]

It's tricky, done wrong it can crack later, or melt away during the process

[632 Regal]

yep has to be heated good and theres special tecniques to get-r-done right.

It's tricky, done wrong it can crack later, or melt away during the process

[Chris'91'525i]

I am looking at picking up a cast iron turbo manifold but its not flanged for an external wastegate - is cast iron weldable?

Yes, I have heard of CI being repaired. They use TIG or Oxy/Acetylene with special Nickle welding rod.
I forget the exact proccess, but I think they grind the length and ends of the crack out after heating the whole manifold and then slowly cool it, after the welding. But , usually do not guarantee it won't happen again.
Contact a local welder or blacksmith for details....

[Bill R.]

arc welder. The alternative is furnace brazing which they use to repair some cracked cylinder heads. I have had pretty good results with the nickeloy rod on large castings such as blocks.

I am looking at picking up a cast iron turbo manifold but its not flanged for an external wastegate - is cast iron weldable?

[Bill R.]

acetylene torch with a big rosebud and a standard arc stick welder... You'll have to have the helper preheat the whole piece up to 500 to 1200 F and keep it around that temp range right up until you start to weld it. Then you weld it only with very short beads, about 1 inch long, then you can lay another bead on top of it and continue with the short beads until the piece is covered. Then you take a ball peen hammer and peen the entire area that you just welded all the time keeping this thing as hot as you can. Then after peening you can go over it again with another layer of weld. Then you let it cool down very slowly on its own. No help such as a fan or water .. You want a slow cool down. If you hear a loud pop when its cooling down you get to start over. After you find where it cracked this time.. Edit, most of the nickeloy rods are pretty machineable.. soft so that they can be easily ground or machined when your done. The monel rods isn't quite as soft.

arc welder. The alternative is furnace brazing which they use to
repair some cracked cylinder heads. I have had pretty good results with the nickeloy rod on large castings such as blocks.

[Jon K]

Well what i'd want to do is drill a hole in it and weld on a ~1.5" flange for a wastegate. Seem possible?

[Bill R.]

.

Well what i'd want to do is drill a hole in it and weld on a ~1.5" flange for a wastegate. Seem possible?

[rob101]

what other car forum in the world would have people able to answer that question? Not alot i'd guess.

forgive my ignorance but you are talking about grey iron aren't you?