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speedsport
09-20-2007, 09:59 PM
My son lives in Houston and can't find a shop that will remove a broken off stud in a exhaust manifold, anybody here from Houston that can provide a name?

Yankee1
09-20-2007, 10:47 PM
My son lives in Houston and can't find a shop that will remove a broken off stud in a exhaust manifold, anybody here from Houston that can provide a name?

Hi,
Have a welder hold a nut with vise grip pliers and weld through the center of the nut to the broken stud. When it cools down he should be able to remove it with a wrench or socket.
Chuck

BadDog
09-20-2007, 11:02 PM
Yep, done the "weld through the nut" trick many times. I've also just built up the broken bolt/stud enough to get vise grips on it. The sudden localized heat shock generally breaks loose even the most stubborn bolts, even exhaust manifold studs.

speedsport
09-20-2007, 11:17 PM
the stud is broken off past the surface, probably need EDM, the shops he has called not interested

Carld
09-20-2007, 11:34 PM
As big as Houston is there should be a shop that will drill it out. It's not that hard to do. They just have to want to do it. He needs to call more shops if no one here steps forward.

Alguy
09-21-2007, 12:00 AM
I have used a cutting torch to blow right thru the stud, i have only needed it couple times and it worked both times,, perhaps a trip to muffler shop one of those guys may have done it in the past.

tattoomike68
09-21-2007, 02:43 AM
the stud is broken off past the surface, probably need EDM, the shops he has called not interested

Nope, heat the stud, let cool, center drill it, hog it hard with a left hand drill and its out of there.

Done it 1,000 times+ and charged big bucks.

I say you owe me for telling the magic trick. :cool:

BadDog
09-21-2007, 02:54 AM
The cutting torch trick only works on through holes. I've done it too, but you can easily wash out the threads. I've welded up With MIG even when below the surface, as long as it's not much.

Left hand drill is convenient, but I've never had that much luck with them. If it's rusted out bad enough to twist off, then the drill generally doesnt work. Combined with enough heat, applied fast enough, it would probably work well though. When you weld up the broken stud enough to get a vise grip on it (or tack on a nut), it often comes as easy as if it were just put in with never-seize.

Ed Tipton
09-21-2007, 09:28 AM
Try this. Take a center punch or transfer punch, and put a dimple in the rusted bolt as close as possible to the center of the bolt. Then, drill out the center of the bolt, and gradually increase the diameter of the drill until you approach the female threads. At that point, take a pick and begin picking the threads apart. Done properly, the threads will uncoil in almost a springlike fashion. It's a little tricky, but once the center of the bolt is drilled out, the rest of the bolt will collapse into the void quite easily, and there is no danger of damaging the threads. I've used this technique many times without ever damaging any of the female threads. It's a little more time consuming, but, if you dont have a torch, it's a safe way to "get er done", and you don't have to have someone else bail you out. Good luck.
If you have a properly sized transfer punch, it makes the job easier.

R W
09-22-2007, 07:09 AM
Drill the stud before heating or welding then if possible run a weld
along the side of the drill hole, this can usually be accomplished with a small sized rod, then weld on a nut or somthing similar. Have removed many broken
studs using this method.

GKman
09-22-2007, 09:03 AM
Better living through chemistery. Get an airesol can of MOPAR rust disolver from your local Chrysler parts counter. My local automotive machine shop has tried them all and uses it by the case.

Ken_Shea
09-22-2007, 10:05 AM
This tip is kinda like purchasing a burglar alarm system after the break in but for future references on the next stud it may help.

I had owned and operated an auto repair for over 30 years and an added exhaust shop for almost twenty. Plenty of bad experiences I can assure you. One trick I found was to heat up the stud area and stud red hot then quick cool it with lots of running water. This does a couple of things, hardens the stud and the quick cool breaks up the rust that wants to screw up your day. Start turning out the stud slowly and when you feel it break loose, stop, spray with penitrant, tighten just till it stops, and back out again, repeating this same cycle until it is free. I had a bunch of 3/8 studs that I kept with less than 1/8 remaining in the diameter using this method.

Ken

Carld
09-22-2007, 11:31 AM
Ken, when I was a diesel mechanic I used that method a lot for studs, bolts and pipe plugs in heads, etc. First I would try heating the stud, bolt, plug to as hot as posible without melting it. Then, with a squeeze bottle with a fine outlet, put water on the heated part untill cool then do as you did. Sometimes I had to reheat and heat the whole area and work the part out. Sometimes I had to heat it up warm enough to melt a candle into the threads to get it out. The candle wax trick works real good on pipe plugs but you need to heat the surrounding area rather than the plug so the wax can get into the threads.

Ken_Shea
09-22-2007, 11:51 AM
Sometimes I had to reheat and heat the whole area and work the part out.

Carld,
Yes to that, had forgotten that this reheating was often necessary and there is no need to be re-heated so hot as Carld mentioned. If you do it only softens the bolt material.

One key asspect is do not get in a hurry, slowly loosen/re-tighten etc.

plastikosmd
09-22-2007, 12:19 PM
hey at least it is iron, try stainless bolts snapped off in blind holes of alum. castings from salt water corrosion..(3 out of 6 darn it)..that is how i spent my saturday a weekend or 2 ago...trying to change a waterpump on a outboard lower end. thank god for TIG. came up with a bunch of new swear words...esp. the one bolt that snapped no less than 4 times in taking it out...every .25 inch out it would snap again.
scott

tecnovist
09-24-2007, 09:36 AM
i shape a pice of steel so i can use it as a lever like a weld on spanner----- so i can start welding on the leaver then put a tack on the stud ---So as to stop & start welding on the leaver chip flux off your tack / botton weld.---- Then repeat untill you have a good build up of Strong weld connecting the leaver to the stud ----- Let the part cool --Then spray with lube you can work it back and forth a bit. Then undo -------NEXT WAY You can drill a hole in the stud then fit a peace of round mild steel in the hole then drill next to it fill that hole with mild steel round -- so as to work you way across the stub -- pull or dig out he round plugs with sharpened up ram set nails and then dig out the stud---tecnovist

awemawson
09-24-2007, 10:30 AM
There are hollow weld through studs available that exhaust (muffler US speak?) shops use when a stud breaks. They hold them over the snapped stud and mig down the hole.

Sunkenmetal
09-24-2007, 02:01 PM
Drill the stuck stud to the minor diameter of the thread pitch, then use a scribe to pick out what is left of the threads.

Or, use an Eazy out..........................................!:eek :

loose nut
09-24-2007, 02:14 PM
Welding rod companies like Certanium and probably others, have special welding rods for removing studs broken below the surface. You strike the arc and hold the rod vertically over the stud and just let the metal build up until it is above the surface, place a nut over the weld buildup and weld it in place. The heat loosens the stud and it unscrews. The flux off of the welding rod flows into the screw threads of the main body and this prevents any of the welding buildup or splatter from ruining the threads. When the stud is out just run a tap through it to clean it up. This really worked well when I've used it.

speedsport
09-24-2007, 09:56 PM
My son found a guy that blew it out with a torch, when he finished you could see the threads, quick clean up with a tap and it was good to go.

TGTool
09-24-2007, 11:39 PM
Now that's a neat trick. I'll have to practice on something and get the feel for that, but I can see how you might bring the bolt up to temperature but not the surrounding metal. Then just a whiff of that oxygen ...

.

tattoomike68
09-25-2007, 12:07 AM
My son found a guy that blew it out with a torch, when he finished you could see the threads, quick clean up with a tap and it was good to go.


You know it... SHHHHHhhhhh, dont tell everyone. that when you charge the fool who broke off an easy-out off in a drilled hole and charge $60-$100 for the one stud... the torch is the last word.

I call that flame boring.. ;)

BadDog
09-25-2007, 12:17 AM
Just to be sure everyone remembers, this is ONLY for a through hole. That trick is old as the hills, but seems 9 out of 10 times, if I have a twisted off bolt I can't get out, it's in a blind hole. The last 2 were in stearing knuckles...

Fasttrack
09-25-2007, 12:18 AM
Heck when that happened to me i just drilled the damn studs out - left me with one of the holes way too big so i just brazed a bit of grade 5 all thread i had lying around in there. So far the brazed joint has lasted with no issues.