Chevy 454 broken exhaust studs...What to do now?

[flash_flood]

I have a 96 Tioga with a 454 that has two busted studs on the exhaust manifold. I couldn't pass up a deal on this thing so I bought knowing it leaked a little but the leak has gotten worse so now the repair.

One of the broken studs sticks out of the manifold hole a little so I should be able to get that one but the other stud broke at the threads inside the head. In fact, there's about two rows of threads left that will thread back and tighten a little. That's obviously how the PO handled it because there's 3 gaskets on this side.

I'm not sure what to do at this point. I live in the Country and the closest dealer want's $1100 to do the job which would require me putting it back together and coughing up the money not to mention delaying our vacation time. How can I get the rest of that stud out or can I thread the busted piece back in and weld it into/onto the head?

[j-d]

Is the one that's broken below the gasket surface where you can even line a drill up on it? If you can, perhaps you can try this:

Buy or make a bushing that fits the manifold hole and centers a 3/16 or 1/4 drill bit. Install the manifold so the bushing centers the drill hole over the center of the stud. Then drill with left-handed drill bit. Might just back the broken piece out. If not, you'll drill your way to a centered hole for a screw extractor.

These exhaust fasteners don't break because they "twisted off" but because they were stressed side-to-side repeatedly by the manifold heating and cooling but at a different rate than the head. The broken piece may be rusted in place but not galled in place like one that broke by twisting.

[Jeff_Barrett]

There are a few options ... buy an "easy-out" and try to get the stud out with that.

The other option is to drill it out and install a Heli-Coil or Perma-Coil product.

[jdog]

If you do not fix it, you will proably burn or warp valves
from colder air leaking back in thru the leak area.

[eubank]

My ancient Honda motorcycle had lots of problems with broken studs. I bought a stud extractor set from Sears. Basically, you drill a hole right up the center of the broken stud, then thread the extractor in. As it has elongated left-hand threads, it goes right in until tight. From that point, you just keep on turning, now unscrewing the broken stud.

🙂
Lynn

[wrgrs50s]

I have repaired a few like this in previous yrs. The one that is sticking out will be simple if you have a welder. The one with no threads sticking out can be more difficult. At the least, you will need to remove the exhaust manifold, then find a nut that is slightly larger than the stud that's sticking out of the head. Place the nut over the stud and weld in the center of the nut, welding it to the stud. After it cools a little, simply back it out.
Since you have one stud that is broke in the head, you will most likely need to remove the head. It will make it much easier for both studs to be removed. The other stud will have to be drilled out dead center of the stud with a bit about half the size/diameter of the stud. Then insert the appropriate size ease out into the drilled stud. lightly tap on it with a hammer and turn slowly to remove the stud. It's a very tedious job. It may be best to just remove the head and take to a local machine shop where they already have all the necessary tools to properly do the job if your uncomfortable with attempting this on your own. Wish I knew of an easier way, but that's about it to do it right.

[ScottG]

After removing the manifold, a good welder can "blow" the stud out pretty easily and not damage the threads at all. I have a welder friend who works on heavy equipment and does this all the time.