MIG welding cast iron exhaust manifold.

[aametalmaster]

You guys know how hard it is sometime to weld an old junky exhaust manifold? I have done hundreds of them over the last 34 years most of them stick with Ni rod and some brazed. Some worked well some didn't. So move ahead 30 years i picked up some Crown Alloys .035 44-30 mig wire for cast iron. Its used with Argon and works great. This manifold on my Geo Metro had a crack and it has been hissing for 4 months or so. I drove the car around to warm it up since i wasn't planning to remove it and hit the crack with a die grinder and a stone. Then i dabbed the mig wire in the clean area and triggered it right up the crack. It took about 30 seconds and sealed the crack right up. I let the car run for a few minutes and then let it cool. So far so good. The 2# spool is 75 bucks and i wanted to try it out for a test...Bob
http://www.crownalloys.com/TechSheet...ew_Warning.pdf

[Daniel]

Looks like a miracle wire for cast iron, looks like it does well, with not so clean parent metal. Did you notice any porosity anywhere in the weld?
I might have to get myself a roll.

[aametalmaster]

The cast has to be clean. I ground where i was going to weld with a die grinder and a stone to shiney metal. The wire stuck perfect to that area. Nope no pin holes. It could have been better if i had more then 2" of room to work in but it was fine...Bob

[metal-doctor]

Keep us posted on how it lasts. New technology is great. Good job , Wayne

[aametalmaster]

I will watch it since its on my daily driver. I didn't want to try it on someone elses ride first...Bob

[jpence38]

That is some awesome wire. I bought a 10# spool and it was worth every cent.
It is so nice to be able to just spot it in quick like that. Much more control than rod.

[Blondie_486]

Hi Bob,
Let us know how it's holding up a month from now. I'm curious. I've never MIG welded a cast exhaust manifold before but sounds a lot quicker than how I've been doing them for a long time now. In the past I've been drilling stop holes at the ends of the crack then veeing them out with a die grinder, pre heating then TIG welding them with some coated 309L filler I've had around for so many years now I can't remember who made them or where I bought them then some post heat and pack in sand to cool. I've not had any problems with this method but yours sounds so much easier and definitely faster especially if you can reach the crack without removing the manifold.

Thanks for sharing this info with us!

[aametalmaster]

I will watch it. I have been driving the car 80-100 milkes a day for the last week and so far the weld is just fine. It was a stress crack from the exhaust hanging on it and i fixed the broken hanger also...Bob