Can you weld cast iron?

http://www.forneyind.com/catalog/detail/406/arc_welding_electrodes/243/18_nomacast_hard_cast_iron_specialty_welding_electrodes_5_lbs/

This stuff works great! Don't run it and weld it you'll pump exhaust in to the weld area and as others have covered fry the ecu. Noracast is best when pre heated but it doesn't need to be glowing and you don't need to lace the crack with steel pins like some other books suggest.

I've fixed a few Ford straight 6 exhaust manifolds and a few "valve cover baking" Mopar big block manifolds with it heat with torch, weld, heat wrap with header wrap and let cool slow

Preheat the whole thing, heat the crack dark red, and shove some brazing wire in there.

jrw1621 wrote: Is this the answer? JB Weld

For 17 years I have been telling our welders this same joke.....can't we just throw some JB weld on that leak?

And they have been rolling their eyes for all 17 years too.

Well not JB weld but this stuff has a great rep from people as it was made just for this. http://www.aremco.com/product/a15/