Exhaust manifold studs corroded beyond use

I have been pulling my exhaust system for replacement, and have discovered that the studs in the right side manifold have corroded to the point that they have no threads left. The nuts are also fused to the studs. I have used Kroil and heat as well as a variety of SAE and metric sockets in an attempt to remove the nuts - to no avail.

I guess I need to remove the studs from the manifold and replace them. What is the best way to approach this? Should they twist out?

TNX

 

If you are lucky, the studs will come out with the nuts attached (like a bolt) and then you can just replace the studs. If you are unlucky like I am then they will break and you'll have to drill them out and possibly have to use a Helicoil as a replacement. Just keep applying penatrating oil and let it soak. You may also try applying heat with a torch. If you have access to an impact gun then that would be your best bet.

 

I assume the studs twist out in the same direction as the nuts? So, if I can get a bite on the nuts the stud should eventually come lose or break?

 

That is correct. Hopefully they will not break on you. Again, if you have access to an impact gun I would use it.

 

You can try a muffler shop to remove any broken studs. In my experience, they can blast the stud out of the manifold with their cutting torch.

 

Thanks much. That may be what I end up doing - after I try all else