So I am in the middle of a timing belt change on my E30 and I managed to break the upper bolt that holds the tensioner pulley (it is sheared off clean, flush with the block).
I've searched around and read articles on e-z out and other methods but other than swearing a whole bunch, I haven't attempted anything. Do you guys/gals have any suggestions on how to get this baby extracted. If not, my next question will be--how easy is it to throw an M20 in the garbage to make way for an M50?
It may feel like a hopeless situation, but with the right tools, it's simply a PITA.
First thing you want to do is heat that block around the sheared off bolt. Next apply paraffin wax to the threads to get it loosened up. Then one thing you can try is to use a punch on the remainder of the bolt in a counter-clockwise direction, as if to try and back it out.
If that doesn't work you are left with several options.
One is to drill the center of the bolt with a properly sized bit and use a "e-z out". This is risky business as too much gusto on the extractor will snap it off in the bolt thereby rendering you worse than before, but still in the fight.
Another option is to drill the I.D. of the BOLT until just the threads of the BOLT remain. Again it's tricky because you are supposed to use a centering fixture or you risk eating the block threads...
Which leads me to the final option... drill the bolt out along with the block threads and tap new.
Really any machine shop worth it's salt could prolly get it out in five minutes.
But of course we are all about DIY here.
Did the bolt break while trying to remove it? If so, it's probably corroded into place meaning you'll wind up using the big guns (heat, like a torch) to get it loose.
If it broke while tightening, the bolt was probably fractured to begin with and that means the broken piece should come out pretty easily. If that's the case, I have in the past used a Dremel and cutoff wheel to make a screwdriver slot in the broken piece and then backed it out. That probably won't work if it's corroded into place.
Either way, the best way to start if you decide against the Dremel slot trick: centerpunch the broken bolt and drill with a LEFT HAND drill bit. A RIGHT HAND (normal) bit will run the broken piece further into the hole. In a lot of cases, the heat and vibration of drilling will make the broken piece back right on out. You might also get a MAPP gas torch and put some heat on it, too. Caution: the O2 cylinders for the little MAPP torches are only good for about 20 minutes, tops.
Keep penetrating oil on it (I have had good luck with PB Blaster). If it was corroded into place, you might as well save a lot of time and keep drilling bigger until the threads are the only thing left, then clear them with a tap. That rarely works out perfectly in the real world, in most cases the drilling is off center enough that only half the threads get drilled out. Now it's Heli Coil time.
Thanks for the suggestions!
Jensenman: The bolt head snapped while going in so I'm thinking that slot trick might be the answer.
Either way I've got enough to keep me busy today.
Generally, if a bolt is so badly stuck that it shears off the head, getting the remainder out will be a bitch. PB Blaster, applied for a few days should be a minimum. Unless you can get through the corrosion, drilling it out and rethreading is the only real option. I have found that the best thing to use is the one thing that I have in very short supply: patience. Soak it in penetrating oil, heat it, ice it, tap it, work slowly, etc. I tend to turn to the drill quickly, then a sledgehammer and make it worse.
If you go the easy-out (misnomer) route, then be sure to read http://www.drhess.net/Clip_n_Saves.htm#How%20to%20remove%20a%20broken%20bolt%20ext...
I'd go at it first with a punch and hammer. Beat it tangentally and they usually come out. Dremmel a slot and try the screwdriver. Try a left handed (reverse drive) drill bit. Take your time and be careful.
Keep in mind if you use an ez out its about 90% probablility it will break, and about the same probability that you wont be able to get it out, and it will cost about 4 times as much when you have someone else do it.
Another method I recently tried on a seriously rusted body bolt was to center a large nut over the broken end, and then really solidly welded the nut via the hole to the thread, this causes enough heat the break the rust and when it cooled the broken bolt undid easily with a ratchet. worked out great with no more damage,
I have nothing to add for advice just some overall support. Hang in there Bro, we have all been in similar situations. Why does averything have to be so difficult?
I'm going to avoid the e-z out method as I read nothing but bad things. I managed to find a left hand drill bit and we'll try that.
On a related note, I called around to see if anyone had the bit and they all responded like I was retarded. If anyone falls into a similar situation Autozone carries them....just don't ask for help.
Ok, time for fun!
Most easy out snap because user try to get away with the smallest one....You need to drill 80-90% of the bolt out. Spring loaded punch the center and start with a small bit and keep working your way up.
44
Good luck.
When you get it out, be sure to chase the threads with the appropriate tap.
Harbor Freight carries left handed drill bits.
Don't mess the HF for drill bits. Get a Hasson set from MSC theres one set that comes with cobalt left bits and the multi spline removers.
They will drill and remove anything.
44
aussiesmg wrote:Another method I recently tried on a seriously rusted body bolt was to center a large nut over the broken end, and then really solidly welded the nut via the hole to the thread, this causes enough heat the break the rust and when it cooled the broken bolt undid easily with a ratchet. worked out great with no more damage,
+1
Tig welder.
I had a similar job last week on a Civic with a broken engine mount bolt. They tried most of the above mentioned methods and suckseded only in wallering out the aluminum around the bolt.
You want to build up a little mountain of filler rod on top of the broken portion of the bolt, then hang a nut on that, and burn it in with more filler. The heat helps the whole situation.
-James
44Dwarf wrote:Most easy out snap because user try to get away with the smallest one....You need to drill 80-90% of the bolt out. Spring loaded punch the center and start with a small bit and keep working your way up.
44
+1 I may not be able to remove an appendix, but I have never broken an EZ-out
jamscal wrote:aussiesmg wrote:Another method I recently tried on a seriously rusted body bolt was to center a large nut over the broken end, and then really solidly welded the nut via the hole to the thread, this causes enough heat the break the rust and when it cooled the broken bolt undid easily with a ratchet. worked out great with no more damage,
+1
Tig welder.
I had a similar job last week on a Civic with a broken engine mount bolt. They tried most of the above mentioned methods and suckseded only in wallering out the aluminum around the bolt.
You want to build up a little mountain of filler rod on top of the broken portion of the bolt, then hang a nut on that, and burn it in with more filler. The heat helps the whole situation.
-James
+1 to james as an excellent explanation of the aussiesmg suggestion. i've seen it done, and it's worked every time.
I third the TIG welder solution. This is a great excuse to go get one. Once you have one a whole new world of car fun comes into reach.
Wally wrote:44Dwarf wrote:Most easy out snap because user try to get away with the smallest one....You need to drill 80-90% of the bolt out. Spring loaded punch the center and start with a small bit and keep working your way up.
44
+1 I may not be able to remove an appendix, but I have never broken an EZ-out
What? You can't remove an appendix? Jeez. 
The left-handed drill bit seemed to be working and then my (or my roommate's) drill decided to take a dump. I was planning on getting a welder....maybe this is the push I need.
Learning to weld on that would not be something I'd want to try. Keep going with the left handed drill bits. What usually happens is that eventually the drill bit will grab the bolt and back it out.
+1 on the LH drill bit; if the bolt sheared going in, they will usually work. If the bolt sheared coming out, you're screwed.
keep on the drilling - good reason to buy your own drill and anew one for your roommate since you broke his.
welding a nut on works great, i've done that many times in the past when i actually have the patience to get out the welder instead of going nuts on it with a drill.
