Hi Skip,
I just used a method to remove broken exhaust studs on a turbo and thought that
this might work for this problem also. I had a welder friend weld onto the
broken exhaust studs with a drop of weld until it was built up enough to grap
with vise grips and it twists right out. This worked very well. It took quite
a few welds to do a difficult one but all the frozen/broken studs came out
this way. The threads were good in 3 out of 4 spots.

I was thinking maybe you could weld a bolt to the insert or just weld directly to it and build it up until it comes out. The intense heat of the welding seems to help. I read about this on an Audi board similiar to the BB. Also the BB has
an archive entry about this technique. The Audi board had a very detailed
write up on tips that helped the job. Here is the text of the Audi post.

BROKEN STUD REMOVAL

Home | Technical | Repair | Broken Stud Removal



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Tech Report: Broken Stud Removal
The MacGuyver victronics silver cross award goes to....
.... Jeff Goggin today for the stud removal procedure he's posted over the years.

After reading Jeff's posts a few times wrt using a welder and some vice grips to remove broken studs, I decided to try the self study course. I did a total of 16 (between 5 heads in my shop yesterday, the last for the actual customer car). After some practice, I'm now confident that the absolute worst studs (totally crudded head, 1/4in recessed stud) can be extracted via this method, leaving a perfectly clean intact and new looking threads in the head. All studs, from *all* heads came out using this method.

The procedure:
Using a welder, slowly build up a bead of weld on top of the stud, until it clears the surface of the head. Using vice grips, grab the weld and twist out the stud remains. I used an oxymig at the slowest wire feed, and a medium high setting (110v 30amp welder) - ground clamp to the #1 cam journal.

The patient:
85 5k fwd, warped exhaust manifold popped #1 and #2 upper and lower studs. This car already had the upgraded studs and washer/nuts found on the later turbo cars.

The problems I encountered:
On a couple of them, the weld would break before the stud would break free. I just kept going at it, rewelding until the stud broke free. Some times this took over 6 applications of the weld bead technique.

Suggestions I found worked:
* On one of the studs, I found that someone had overtorqued the stud so that it ruined the top threads of the hole. I used a drill bit and opened up the hole a bit until it had slightly cut the top threads. Then rocked the stud back and forth (applying some WD) until it cut it's way out of the top threads
* Another stud I found was really in the head solidly. After 6 repeated attempts, I drilled two holes and made a slot in the top of the stud, then did the weld technique again (effectively welding a screwdriver tip into the stud).
* Yet another stud broke free (finger tight) just by applying the first weld bead to it (adding credence to Jeff's surmise that the effect of the weld electrolysis itself loosens the bond between the two materials)
* Using a hammer on the top of the bead each time, I tempered the bead, which appeared to reduce the chances of shearing the bead off the stud.
* Allowing each bead to cool before adding more material, is the key to getting this right.
* I used the slowest wire feed setting on my welder (mig - med high amp setting) basically dropping weld beads onto weld beads.

As this was my first attempt at this procedure, I took the easy route (85 5k fwd) and pulled the head to get the studs out on the customer car. I have no doubt that this procedure can be done in the car, it's just a tougher job, and if number 4 or 5 is toasted, bigger than just removing the head itself.

I found that someone had been in this car before, and didn't shave the manifold, and it was really not flat. Don't replace the studs if you *aren't* going to get the manifold machined, or you will be doing the project again really soon.

This procedure negates *any* need for the drill and helicoil procedure even the dealer uses. The biggest problem with the drill and helicoil is getting a straight hole, and not going thru to the water jacket beneath.

Kudos Jeff, I'm a believer, the "knife" is yours sir. I tried calling Jeff yesterday, but didn't get him, so I called Lawson and shared the awesome nerd btdt. This procedure beggers belief until you give it a try.... From a customer perspective, I doubt this procedure is any *cheaper* in terms of actual time/cost, but it certainly is the right and better way to fix this common Audi malady.

- original post

Scott Justusson
Stud Removal Specialist Emeritus
QSHIPQ Performance Tuning


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I have used this technique successfully many times over the years to extract bolts and studs from far more than just cylinder heads. Given the major grief these jobs usually are, it's hard not to laugh the first time you try it.

However, I can't claim credit for the discovery. That belongs to Chris Harrison, machinist/fabricator extraordinaire and proprietor of Harrison Autodynamics, a racecar shop in Phoenix, Arizona. He demonstrated it to me by removing a broken bolt in an alternator case while simultaneously eating
the lunch I'd brought him as a bribe to fix it for me. The key to its success, in my opinion, isn't electrolysis but the concentrated application of heat, which breaks the corrosion and/or galvanic bonds between the steel stud/bolt and the aluminum casting.

Anyway, it really does work a treat and if you've got a welder handy, it's definitely worth a try the next time fate deals you a bum hand. Like Scott, my track record with it to date is 100%.

- original post

Jeff Goggin
Scottsdale, AZ





Last updated: 06.09.02
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Hope this helps you. Worked great on my turbo exhaust studs.
Dave 82 242ti 278k mi.