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Discussion Starter #1
The allen screw that holds the rotor on - if it is stuck on badly - like PB Blaster and a hammer impact device with an allen fitting (do not know what it is technically called but you add on the head and put it in the screw and smack it with a hammer) fails to budge it I know of 3 choices:

1) drill the screw out. What do I need to look for in a drill bit or will any drill bit work? I assume all I will need to do is get a bit just a little bit smaller than the screw?

2) Use heat with a propane torch.

3) Or - as someone who has a E36 M3 race car suggested - remove the cover on the back and use a hand sledge to break the rotor.

I see 1 & 3 being my only real good choices. Any other ones?

I will be doing this tomorrow afternoon - I have a friend from work coming over to help and I have PBlaster soaking in now. Unfortunately, I don't have high hopes that this screw is going to be coming out easily....

Thanks,

Brian
 

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Strange it's in so tight. It should of only been torqued to something like 10-ft/lbs. I'd drill it out before I start taking a sledge to the rotor.
 

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out of those options I'd drill it out - according to realoem the bolt is M8 so you will want to use something around 6.8mm. Start with a center punch and a smaller diameter bit like 2.5mm. Use tap oil and HSS drill bits.

With any luck you can do it without screwing up the threads, but you don't really need that bolt there so don't freak out if you screw it up.
 

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Discussion Starter #4
Strange it's in so tight. It should of only been torqued to something like 10-ft/lbs. I'd drill it out before I start taking a sledge to the rotor.
It is just corroded - live in Ohio. It was the only one like that and I am going to use some anti-seize on the screw(s) as well. I knew about this ahead of time when I was doing work on the car with a good friend just after I bought the car and he was loosening up the screws and found we could not get this one loose. We added anti-seize as well on all of the other ones.
 

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Discussion Starter #9
Well - nothing worked - had to smack the backside of the rotor ands then it fell off when the head of the screwbroke away. Tried one more time to use an extractor and it did nothing. Gave up - still have the screw body in the hole.

Broke one extractor bit and both bits I used - when the head bit - the drill stopped dead in its tracks and wold not turn the screw at all.
 

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Discussion Starter #10
One last question - when the rotors are changed - especially the rear - do you need to re-adjust the ebrake?

The bolts on the back of the problematic rotor took us standing on the wrench to get the bolts to turn. I weigh 190 and I had to bounce to get the bottom bolt off. My friend who was helping is probably a little north of that weight...
 

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use an impact allen or hammer a slightly bigger allen into the hole and use an impact to unscrew it,then go to the stealer and get new ones for $2 each
 

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Discussion Starter #13
use an impact allen or hammer a slightly bigger allen into the hole and use an impact to unscrew it,then go to the stealer and get new ones for $2 each
The head of the screw broke off - a friend tried an impact allen weeks aso - it did nothing. PB Blaster likewise did nothing. A screw extractor bit broke off when the bit, bit into the screw head and stopped the drill in its tracks (2 times with 2 different drills).
 

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drill it out or if you got the rotor off use a cutoff wheel on it.

if I had an experience like that I'd never put that bolt back in anyways!
 

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Most likely not. Make the judgment after you finish. If it needs tightening, it's an easy job.
Make SURE you check first. If they've been readjusted for wear, they will be pushing out further and the new rotor might rub--happened to me, it dragged the parking brake on one wheel a few miles before I noticed all the heat and brake smell. Not good.
 
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