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Discussion Starter #1
Things were going just fine on the first three rotors of this brake job. But the driver's front rotor?

:censor::censor::censor:

The bolt is stripped. I found some other threads on this, and tried several of the techniques:

1) The screw removal bit broke when trying to use pliers to turn the screw and removal bit out.
2) I tried drilling a few holes and then using a dremel with a cutoff disk to make new slots, but all I wound up with was a ton of broken cutoff disks and a messed up head.
3) I tried whacking the rotor from behind with a sledge, hoping the head of the bolt head was weak enough and would break off. No luck.
3) I think I've gone through a whole can of Liquid Wrench on it.

Attached is a photo of what it looks like now. Any ideas? I've already spent more time on this one bolt than the entire rest of the brake job.

Neil
 

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Have you tried to heat up the bolt?

That's why it's good to hammer the allen bit in any allen bolt. It helps drive the bit in and loosens it up a bit.
 

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There's the slam a chisel from an angle to get it started technique.

Guys have really slammed with sledge to break it off, but at that point, I guess they're replacing the rotor...maybe not.

heat with torch?

Extractor from local auto/hardware store?

Drill a hole inside it and get proper sized extractor.

Good luck.

HTH
 

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dont even sweat it.. if it broke at the dealer this what we do.. either get a bfh and hit the rotor from the inside till the rotor broke off around the bolt or use a air hammer and a chissel bit and work it loose. once the rotor is off your left with a donut of material around the bolt, hammer it off to.
clint
 

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Discussion Starter #8
Thanks for the tips, folks. Clint, basically I can wail on this with my 6 lb sledge with no fear of damage elsewhere? Assuming, of course, my aim is true and I steer clear of parts behind it :)

Sadly I don't own an air hammer.

Neil
 

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Discussion Starter #9
1. Get screwdriver
2. Put head of screwdriver in top grove and lean screwdriver to the right
3. A few hits on the screwdriver with a hammer should break the bolt free.
Tried that a couple of times already, but will go try again. :banghead:

Neil
 

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first....the bolt is seized so before you try to remove it you need to apply PB Blaster. Do not use WD-40 or any cheap penetrating oil alternative. it needs to be PB Blaster. spray PB blaster on that bolt and let it work its magic for 15 mins. come back and try to twist it with a screw driver. if that doesn't work then heat up the bolt with a blow torch and try again removing it. if all fails then do what DMAX suggested by removing the head.
 

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Ironman
01 330iT 6MT, 98 M Roadster
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A manual impact driver is the best solution for a retaining bolt that does not want to come out (before you booger it up).

 

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I mig welded a nut to mine and ratcheted it off. It's an option if you have access to a welder.
used to do that kind of stuff offroading. saved my ass many times!!
 

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Drilled mine to like .01" from the threading. Then used a extractor to get it out. Don't get Pissed at it and start using power tools: mess up the threading and bye bye rotors. Take a coffee break, walk it off, masturbate, **** your girlfriend...come back and it will be 20x easier with your head (top one) clear
 

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It shouldnt take that many hits. the material surrounding the bolt isnt that thick. i'd say 1-2 good hits should do the trick. You could even try to use a chissel and hammer and have someone press the brake to keep the rotor from spinning if you wanna try that first. really there arnt any other options that whats already been given.
clint
 

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Discussion Starter #17
I love the idea of welding a nut on. Hmm, a good reason to buy my first welding setup? :)

At this point I think I'm going to go get a stronger drill bit, drill out the broken extractor, dump some PB on it (I've been using Liquid Wrench), and then try one of the bigger extractor bits I have.

You can bet that on the other three rotors I put anti sieze on the damn bolts.

Neil
 

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I used to work in a factory, where we assembled machines, as an engineer. For some reason, I developed a reputation for being able to extract broken, stripped bolts and screws. You can not send out a brand new $500k machine with a stripped bolt in it. So, this is what learned. The biggest issue here is that people don't stop until it is a real mess. The other issue is they try one fix at a time. You need to use everything you know, as soon as a problem develops. I agree with the PB Blaster suggestion. Also with the. Manual impact driver. You already broke off an extractor, so that is bad. It is nearly impossible to drill out. Also, you need a proper holder for the extractor, and you most likely used an undersized one. Keep it soaked in PB Blaster for as long as possible. At this point, I would advise a heavier cutting wheel, to cut a groove or an X in it. Heating it works OK, but you have to realize one thing. The heat expands the metal part with the thread, which makes the threads grip the screw less. But it also heats the screw, which expands it as well, and fills up the space you gained by heating the threaded piece. So, heat it up, but then hit the head of the screw with a blast of Freon, which will shrink the screw. Don't do it so long that the wheel hub begins to cool off. Use the manual impact driver in the slot or X you cut in it. Hopefully, this will get it out. I have removed hundeds of broken or stripped bolts and screws. It is a pain, and it requires lots of patience. If you get pissed, walk away until you cool off. Sorry I can not help more than that. In the future, escalate to a proper sized extractor, with a proper holder as soon as you know you have an issue.
 

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Discussion Starter #19
I have a manual impact driver, but none of the bits with it are big enough to bite the groove across the entire width of the head. It just bites into half the diameter of the head, and then does nothing useful.

Neil
 

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I want to add one thing to my post above. One day, I spent 6 hrs removing a bolt that the head had broken off of. It was on a machine that was ready to ship, so there was a truck and a rigging crew waiting for it. When I finally got it out, I was so mad that I threw it across the production floor. It skipped right into an open electrical box for the main power supply on another machine, and promptly blew up a good portion of the electrical components. $16k in damage. That is when I learned that the plant manager was a pretty cool guy, and that I had to learn more patience.
 
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