help please - removing broken exhaust stud..

I had a slight leak from the right front header pipe so tried to adjust the header bolts. I was pretty gentle with a small spanner, but even so the damn stud snapped. (see pics). The other stud came out with the bolt.... It's a '99 VFR. I spoke to a local garage who said VFRs were renown for snapping exhaust studs and you can end up breaking away part of the engine casing when trying to get it out. Worst case it could cost $300+!! So grateful for any advice on how I might get the stud out safely...... Many thanks.

 

A Professional mechanic might have a bolt extractor tool which has jaws to grab the stud so it can be backed out. The jaws tighten as the tool rotates counter clockwise to bite harder as more force is applied.

You have a couple of options, try to extract or drill it out. To extract i would put some oil of wintergreen or your favorite rust-disolving liquid on there to let it soak in good. Then smack around the boss with a small hammer (not a 3 lb sledgie torque hammer) and on the end of the stud to try to break the rust and oxidation loose, Then heat the aluminum of the head boss with a torch and tap around with the hammer some more. Soak, tap, heat, tap, and repeat. Finally after several cycles heat the boss again and use the bolt extractor or vise grip pliers to grab the stud and back it out.

If (when) the stud breaks off again, then you have to drill it out. Or you could use a dremel tool with a cutoff wheel to cut the stud cleanly leaving a flat surface parallel to the head boss face. Then center punch the stud and use a small bit to drill a center hole. Move to progressively larger bits to enlarge the center hole until the stud is nearly drilled out. Then using the wintergreen/heat/hammer method above you might be able to extract the remainder using a screw extractor bit, which has left-hand threads to bite into the center hole of the stud as you turn it counter clockwise.

i have a small collection of broken bits, studs and bolts that i have extracted over the years using these techniques-- have to be patient and not try to force it until it's ready. Heat and vibration will be your friends here.

 

^^^^^^^++++1 What kenny said

 

Typical steel stud in aluminum. The easiest way is to take a drift pin or like and put it on the end of the stud then hit it with a hammer solid about two to three times. This will shock the threads and break them lose from each other. Then use a good pair of vise grips to turn it out. If you can get a stud puller it would be better, may be.

Type of stud puller to use: http://www.amazon.com/Lisle-71200-S...F8&qid=1414246452&sr=8-5&keywords=stud+puller

 

Or you could buy a good quality damaged bolt extractor bit, or a whole kit. You drill a hole in the center, very important, and it threads in RH so the more you turn it in the more it forces the bolt out. Get that in to that stud, apply some heat,(a plumbers propane torch will work) and it'll come out. Go to someone like MAC tools, or Snap-On, or Acklands(in Canada) for bolt extractor. You can order their products online now, so you do not need to hunt down a dude in a truck.

 

You may have to have someone do it but welding a nut on the stud, letting it cool, and then using the nut to back out the stud will almost always work. The heat from the welding will expand the stud, and loosen when it cools. With as much of the stud showing as you have, that is what I would try first.

 

started soaking it last night and been to the hardware store to buy a stud extractor. Going to do some heat cycling and tapping tomorrow, after another night of soaking in penetrating oil.

I'm going to have to take the front headers off to get the extractor on. Can't face trying to touch the rear headers.

Can I get the front headers off on their own by taking off the muffler and disconnecting where the rear headers join the collector? And do I need to get new gaskets to fit for where I disconnect the rear headers from the rest of the pipe?

 

I feel your pain. I had to replace the front headers/collector on my 84.

The pipes on the collector that receive the rear headers will be crushed slightly due to the clamps. The "gaskets" are actually graphite(?) tubes and you'll likely have to dig them out. Use a pipe expander on the collector and expand the tubes just enough so you can slip in the new gaskets. After you get done test fitting them in the collector, slip the new gaskets over the rear headers first and then slide the collector up over them. If you have a problem with the front gaskets falling out when putting the headers on, use a thin coat of high-temp silicone on one side to stick them in place. I let mine dry overnight.

 

This is what I would recommended as well. The punch and vise grip idea sounds nice in theory but 98% of the time doesn't work. Avoid the drill+extractor route. They shatter super easy and trying to drill out the left overs... well doesn't really work. I would also avoid sitting there with a torch roasting an aluminum block. Good way to warp heads.

 

Difficult for me to get a nut welded on since nowhere nearby to do it. Would heating the stud - letting it cool then trying the extactor on it be ok?

 

It is a touchy situation which can work out really easy or turn bad fast.


This is called an easy-out. It is a snap-on tool that works very well if you are able to drill a hole of the correct diameter down the center of the stud. In this picture it has successfully extracted an exhaust stud from the front cylinder of my 07. Last weekend it actually broke off inside a stud that I was attempting to remove from the transmission of our mini cooper. That was fun. After a tool like this breaks off it needs to be drilled out and then the stud needs to be drilled out and a heli coil installed. So it isn't the end of the world but it is a stressful situation even for someone who has done many of them over the years so don't feel bad seeking assistance. No if you do and they fuck it up, that's another situation.

 

For the OP here are some tips to removing broken hardware: 10 Tricks to remove that Stuck, Seized, or Stripped Bolt/Nut

Most of these have been recommend already but good info just the same. I would also recommend the welding nut route if at all possible. If you have to remove the header completely personally I would consider getting a nut breaker. Just like its name implies this tool will crack/ break the nut. You can also use a Dremel type tool to make relief cuts in the nut. Then carefully chip it off with a chisel. The idea here is eliminate the possibility of breaking another stud. If your going try removing the nuts, hit them with a wire brush to remove any rust build up first. Then soak 'em with penetrating fluid. Any method you use PATIENCE is the key. Take you time & keep a cool head.

When it comes to stud removers this is design I've used over the years. They grip turning in both directions & are only about an inch in diameter. Plus you can use a 3/8 drive tool, a wrench or a socket to turn it. That gives you great flexibility when working in tight spots. They come in sets of 3 or 4 and cost anywhere from $30-50 USD.




Over the years I've found that you usually end up combining methods to removed broken/ stubborn hardware. A little penetrating fluid, some heat, work the nut back 'n forth. Repeat. Bolt extracting like anything else is a skill. The more you do it, the better you get at it. I can't over emphasize taking your time with this.

 

On small studs like yours if you weld a nut on it it will most likely break off at the case surface. Why did it break in the first place? Because the threads are stuck together. If you don't loosen the threads by shocking them, then you will have to use the other methods of drilling it out. Hopefully you can keep close to the center of the stud or you will oblong the hole. Then the next bet is a helicoil type fix. You're in a tuff spot to work which makes drilling etc difficult. A little heat is fine. You're just going to heat it some not blow torch it to a death melt. No you won't warp a head like some suggest.

Then again this all depends on your mechanical skills. Some guys can break a bowling ball in a sand box. So keep them away.

 

Owing to a bit of Sunday frustration, now have 2 sheared studs protruding - one each side to match! Interestingly, they are both on the outside of their cylinders. The inside studs/bolts came away not problem. Going to take it much slower now - and try penetrating oil each day and a bit of heat and force. One question - do I let the stud cool before trying the extractor? I think I snapped the other since it was still hot from the flame (but nowhere near red hot). Getting a bit demoralised with the thing tbh.

 

clean the threads and use rust disolver before messing around with exhaust fasteners.

If you are heating the studs to break the corrosion bond, then you must let them cool before trying to remove. Otherwise the stud has expanded larger than the hole from which it is threaded=not going to work.

If you are heating the case area in order to extract the stud, then you want the stud to be colder in order to take advantage of the thermal expansion difference--don't put any heat on the stud if possible.

 

If you have to drill the studs, grind a flat spot in the stud face. Use a center punch to put a dimple in the stud. This helps greatly in making sure you drill down the center of the stud.

 

2 sheared? Geeze man. Well I guess when I need to remove my headers on my 99 I'll soak the old nuts in pblaster and then use a nut splitter and crack them off the studs.

 

Same thing happened to me got it out with tapping and a small set of vise grips :tickled_pink:

 

Epilogue. Finally got it fixed today. Thanks for all the advice. Here's how it went. Hopefully this info and thread will be useful to someone in future who has the misfortune to snap an exhuast header bolt!

The reason the front header was blowing was the fiber gaskets were rotten and partially disintegrated on the cylinder side. They were less than about 2000 miles old, the previous owner had had the downpipes changed for stainless items about 5 years back.

The 2 sticking nuts were on solid, and I sheared the studs trying to remove the nuts with far less pressure than I expected. They felt like they were turning at first, but it was just the stud shearing! I got one stud out by a process of lots of penetrating oil, and tapping the stud repeatedly with hammer and and a drift, not too hard, but for a few minutes at at time (like a woodpecker might!). Then heated the aluminium around it (blowtorch for about 60 secs - recommend putting a head-shield over the starter cable since the outer sheath melts really easily! A bit of plumbers asbsetos mat cut to size did the trick - it was cheap too). Then using mole grips on the stud, rocked the stud back and forward until it started to release. Even then, wouldn't come out cleanly at first, just rock a few degrees either way, so more rocking, penetrating fluid (left for a while), then heating again, and slowly I could rock it further and further round. The mole grips gave a better purchase than the stud puller and I'd use mole grips in preference again, but the latter was useful to speed up getting it out when it eventually got loose; the other problem I had with the puller is there is a bit of elastic movement in it, and it's hard to tell the difference between the puller giving a bit and the stud starting the shear! I can see how the 'welding a nut on the end' would have worked well - if I'd had a welder. The threads were slightly chewed when got the stud out. I think that might have been because of an enthusiastic couple of hard whacks with a hammer and drift, out of frustration earlier on, so next time I'd be more careful about how hard I hit it. It only needed gentled taps in the end, but a lot of them.

The other stud was not so obliging. (Might have been because I really whacked it hard trying to loosen the nut!) Had to take it into a local garage. A large bolt was drilled out and a slit cut down the side. it was then slid over the stud, tack welded and used to try to ease the bolt out (after the head had been heated again).. No luck, and eventually the bolt sheared just inside the head. Then a labourious and anxiety ridden process of very careful drilling, tapping and helicoil inserting.

Have replaced the studs with stainless studs, stainless nuts, and lots of copper slip, and copper gaskets not fibre. Next time though, if I ever have to remove another header, I'd seriously consider splitting the bolts off. Getting the studs out was not a nice job. I must have spent over 6 hrs struggling with it. Result at last.

Only problem now is how to repair the graphite gasket in the muffler since I had the muffler on and off so often!

 

Whew!! That sounds like lots of work, but glad it finally got done. Make sure you goop up the stainless studs/nuts with high heat anti-seize since stainless will gall up relatively easily.