broken headstud (not exhaust)

[TrAnScEnDeNt]

Howdy, new to the forum here, been reading for a while, really like the info. I have 2 gs's and a big problem on 1. i have already searched on here for a fix but only came upon how to fix exhaust studs, so hopefully some1 will have something to help.

On my 79 gs1000 i have a broken headstud. i removed the head and found one of the studs to be sticking up above the jugs (cylinders) about 1". It broke righe below the threads, since it was already screwed up i decided to drill a small hole through it's diameter and stick a little hard bolt in the hole and try to turn it with vise grips and a BFH.

No luck! Any advise?

 

[SgtRauksauff]

I got the following from a Volvo board, but it was third or fourth-hand on there. It's involving manifold studs, but the procedure will help head studs as well.:

Here is a copy/paste of the welding technique from an Audi tech board. I also use Timesert repair inserts for a very strong repair. Helicoils are not good enough.
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
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

I personally used a drill, but the stupid thing ended up going off center, so I plugged the hole with a junk hex-wrench, and drilled right next to it. This gave me a slotted area. I then took the shaft of an old screwdriver and jammed the end into where I'd drilled the slot. I then just cranked up the current on my welder, and welded on the end of the screwdriver shaft. then I took a vise-grips, and turned the stud out by hand. This was a Stainless steel stud in an aluminum head, btw.

Might sound kind of wierd, but this seriously works easy as pie, I HIGHLY recommend this method if you've got the tools and/or space...

What I'd do, since you have some of the stud sticking out, is put a nut over the top of it, and weld the nut to the broken part of the stud. Then, just put a wrench on the nut and unscrew. The current traveling between the stud and the block should be enough to loosen anything binding the threads. PB blaster on it while it's still warm can help too, it sort of wicks in there and helps too.

Good luck!!

--sarge

 

[bleeble]

...or you could do it the easy way. Grab a pipe wrench. ;-)

 

[SgtRauksauff]

I've had bolts pull out all the threads before, leaving a smooth bore that needed to be retapped to the next size. I'd be worried about that with a pipe wrench. maybe just some heat, and PB blaster will do the trick to, if repeated every few hours for a couple days...

--sarge

 

[Guest]

You need to pull the cylinders and remove the cylinder stud and replace it. You might need a stud remover but a vice grip should do the job.

 

[bleeble]

Bah! You guys and your fancy tools... As SgtRauksauff said, make sure you shoot some penetrating oil down the stud before you do anything. Might as well make it a multi-day soak thing, like with exhaust studs/bolts.

 

[Guest]

i'm with chef, you need to take the head off

it's not about fancy tools... those studs are loctited in place so unless you can get a good grip on it (vice grips will do) you wont be able to take it out...

 

[Steve]

You need to pull the cylinders and remove the cylinder stud and replace it. ...

i'm with chef, you need to take the head off ...

Well, guys, it sounds like he's been there and done that.

On my 79 gs1000 i have a broken headstud. i removed the head and found one of the studs to be sticking up above the jugs (cylinders) about 1". ...

 

[TrAnScEnDeNt]

Thanks for the info, i've already tried the soak it with PB for a few days and vise grips (flattened out the teeth on the ol' vise grips). i guess i'll do the "weldanut" technique. gracias.

 

[Suzuki mad]

I'm going to sound daft but here goes.

How much of the stud is left? Did it break just above the base gasket or just below
the cylinder head.

Before going to mad at it just check the thread as it may be the opposite way like a stud.

I would also suggest that if you have a tap and die set, tap a new thread to the remaining stud and using 2 nuts draw the stud out.

Suzuki mad

 

[hampshirehog]

Get some heat on it if it's that tight - you don't want to snap it off down in the threads.

 

[Guest]

Well, guys, it sounds like he's been there and done that.

I said cylinder. ;-)

Check APE or Schnitz for a stud remover.

 

[rapidray]

Ok, as an engine builder, I will tell you what you need to do & if you don't want to do it CORRECTLY you're on your own. And I don't EVEN want to hear you come back on here whining if you break it because you wouldn't listen! You need to remove the head & cylinder because you need to grip the stud lower to remove it so you don't TWIST the stud off in the cases! A stud puller is the right tool to use but you can grab it with Vise Grips also & do it that way. If it seems hard to break loose, try TIGHTENING it just a hair & then unscrew it. What chef told you is the CORRECT way to do the job. Good luck, Ray.

 

[GrampsUK]

Has nobody heard of EASYOUT extractors find them here. http://buy1.snapon.com/catalog/tools.asp?tool=all&Group_ID=1261&store=snapon-store


Mark