Help desperatel needed - pictures included.

[GHEN]

So for those of you that avidily follow my posts (there must be a least one) you know I put headers in my car and used the Rennbay exhaust manifold studs to replace the factory ones. These are really nice and the Allen receptacles in the heads are a great help.

Having said that, one of the studs has proven to be very problematic. I initially put in in by hand and only went a couple of turns before it stuck. I used the Allen key to try and tighten it further thinking there was just a "rough spot" I had to get past. Well no dice and by then (only another 1/4 turn or so) this thing was so stuck that there is no way I can get it out. I have even stripped the allen receptacle on the top.

Here is what I have done, or considered and discarded as a solution so far.

• Double Nut Technique. - Didn't work, these are stainless steel and apparently the material is too smooth.
• I bought a set of stud extractors and tried them. All they really succeeded in doing was chewing up the threads to the point where they won't grab the stud anymore
• Welding a nut to the stud. - No can do...it is stainless steel and I don't have access to a welder (noun or adjective)
• Get the engine heated up and then grab it with a pair of Vice Grips - Wouldn't budge.
• File flats on the stud and grab with a pair of Vice Grips - I am hesitant to destroy the stud at this point.

So what I am considering is this:

1. Buying an M8X1.25 die and recutting the threads on the stud,
2. Getting a stack of washers and use them as a spacer and put a crush nut on there.

This way I will be able to move forward AND if the damn thing ever does come loose enough to come out while driving the worse thing I lose is a nut and some washers.

Your thoughts are welcome and thanks in advance.

GHEN

[emoore924]

Not going to sound like the greatest idea but you might want to back off the other nuts a little, see if you can move the manifold just a little, then double nut the stud and see if that helps. It looks like the stud might be a little off-center in the hole and the manifold is jammed against it and holding the stud in. BTW, when you double-nut, put the wrench on the inside nut when you try and remove the stud Also, make sure you're starting the right end of the stud in the hole. They often have more threads on one end than the other.

[John_AZ]

GHEN,

Excellent pictures and explanation of work to date on the "stud".

I understand your progress and the only possible explanation I can think of is the headers are preventing the stud removal/installation.

Knowing the work it took to get the headers UP and against the block ....I can only suggest removing all the exhaust studs you have installed and hopefully shifting the headers to free the problem stud.

The new headers may be "off" a perfect fit.

Good luck.
John

[gtroth]

You might be fighting 'galling' - a miracle of metalurgy that is fairly common when stainless and aluminum drag across one another at very high force. Basically a weld that's unbelievably strong.
I think I'd heat it with a torch, bang on it with a hammer and turn it while it's still hot.

[IS300]

I agree take the headers off...... you'll have more room to work....good luck !!!

[DannoXYZ]

There's not enough material on the stud to have any useable-threads after you re-cut it a die. A rolling-die perhaps, but you'd need to remove the stud to put it through one.

1. Take the headers off
2. Double-nut again, align them so that flats on both are parallel & even
3. weld outside & inside edge of nuts to stud
4. use deep 6-sided socket to remove

[James Chimney]

did you try tightening it and then loosening it again? I agree, remove the headers, more room to work and heat the head, double Nut and Weld the nuts together.

[GHEN]

Thanks for all of the assistance everyone.

It seems the most possible culprit is the headers; I should have mentioned I installed the studs without the headers in place, the sticking problem happened then; although it is possible they are holding the stud in place more then the stud is holding itself.

"I love my car, I love my car, I love my car..."

GHEN

[JoshB]

I would remove the headers and then try a baby pipe wrench. You need to get that stud out and put a new one in for sure.

[Rod Schneider]

Originally Posted by gtroth

You might be fighting 'galling' - a miracle of metalurgy that is fairly common when stainless and aluminum drag across one another at very high force. Basically a weld that's unbelievably strong.
I think I'd heat it with a torch, bang on it with a hammer and turn it while it's still hot.

This is the most likely problem.......
If you do get the stud out, be prepared to repair the threads in the head. If you are lucky, you'll be able to run a tap in and fix the threads. More than likely, you are looking at a heli-coil type repair..........