Exhaust Stud is exhausted

[Silverscout]

Where are you guys on the removal of the front exhaust stud? While putting in new exhaust donuts, I stripped the forward exhaust stud (that stud that goes from the manifold to the collector). I heated the stud and attempted to remove it with the torque bit, what do you know it snap. I tried drilling it out from above, but I walked the drill bit, putting the manifold threads at risk. Is there a better way to remove this stud, other than pulling the exhaust manifold and Hannah sliders off and removing it from bellow?

 

[Broski]

If you weld and can reach in there weld a not on it.

 

[Marvelicious]

If you weld and can reach in there weld a not on it.

This right here! Sure fire winner: you get fresh surfaces to put a socket on, and pour a bunch of heat into the fastener at the same time. Usually, it'll come right out after.

 

[Silverscout]

Love the idea, seriously. I’m not going to weld it from underneath (0 experience) but I can get a nut on the top of it. However, the bolt is next to an upright portion of the exhaust manifold, so it’ll need to be a smaller nut so it’ll spin. Is it enough material to connect the two or am I just spinning my wheels?

 

[Broski]

Love the idea, seriously. I’m not going to weld it from underneath (0 experience) but I can get a nut on the top of it. However, the bolt is next to an upright portion of the exhaust manifold, so it’ll need to be a smaller nut so it’ll spin. Is it enough material to connect the two or am I just spinning my wheels?

Really if you have the welder and can pull the trigger you can do it.
If it’s a mig you just need to point the wire into the open hole of the nut same with a stick welder.
With any luck some anti-splatter would hold the nut in place for you weld.
You can do it.

 

[Mat Jadamec]

After trying heat and penetrating oils with no luck, I pulled the manifold and set it up on a drill press. The head to pipe angle is roughly 90 degrees so its pretty easy to set up to drill it straight. The manifold studs broke free surprisingly easily.

P.S. Ok, this is not easy if you want to preserve the original threads.

 

[fjbj40]

A word of warning, they can be absolute pricks to extract, even with manifold off the engine.
I did one and even though manifold was heated cherry red when the stud came out it took half the threads out of the manifold.
After some research here that seems to happen and they can be horrible!

Hope it goes well for you

 

[BigRedBJ]

I did the same thing on Thursday this week, after weeks of soaking the stud and nut in ATF/acetone and PB Blaster I needed a nut removal tool to break the stripped nut off.

I used MAP gas to heat up the manifold until it was red before using stud removal tool that pinches the stud to remove the stud which it broke it off.

I took the manifold off and used a vice to hold it on a drill press to drill out the stud, I only broke one bit, thankfully it didn't stick in the remaining bit of stud.

In the end I only drilled a small amount of my manifold by accident but not so much that it affected the new stud going in.

Now I have a nice place to put the penetration fluid next time. I really hope there isn't a next time. For the other buggered stud on my in rear manifold, which is much harder to remove I purchased a 10*1.25 die and re.-threaded the stud in place, a quarter turn at a time which worked perfectly.
Honestly, with the air intake pipe removed and an impact wrench, removing the 6 bolts for the manifold was the easiest part of my day.
I was replacing the whole front section of my exhaust and cats, which seems to be successful.

Best of luck!

 

[TurboDennis]

A word of warning, they can be absolute pricks to extract, even with manifold off the engine.
I did one and even though manifold was heated cherry red when the stud came out it took half the threads out of the manifold.
After some research here that seems to happen and they can be horrible!

Hope it goes well for you

^ this.

Most of these that i had to remove presented "typical" problems for an old exhaust fastener and required "typical solutions".

However this one truck i had to do it on recently was an absolute nightmare. Even with the manifold on the bench, absolutely NOTHING worked to get the broken stud out - oxy torches, heating it with tig, welding nuts onto it, soaking in penetrating oils, heating/shock cooling, etc.. - NOTHING.
To make matters worse, the stud is made from some sort of stainless alloy, which is very hard and extremely difficult to drill. It gets even harder after multiple attempts to remove it (phenomenon known as "work hardening"). I ended up having to put it into a mill, and milling the old stud out with a carbide end mill. Even then, when the diameter of the milled hole was equal to to the minor diameter of the stud (main shaft of the stud completely gone), the remnants of the stud's thread were still stuck in the threads of the manifold and required torches to pick out. The strangest part of this ordeal was that it was a southern truck, and the exhaust wasn't even rusty.