Stuck Caliper Bolts???

[1984M3]

I'm trying to install my brembo bbk but ran into an issue with the 2 caliper bolts holding the stock calipers on. I've hit them both with penetrating oil but they won't budge at all. I've tried to hitting the heads of the bolts with a hammer to try and loosen the corrosion but no dice in getting them to break free. Any suggestions on the best way to get these free? Also, these are not reverse threaded, correct? I want to make sure that I'm trying to loosen in the right direction so you never know.

[Merked M3]

I absolutely feel you on this one. I got the fronts off by hitting the ratchet arm with a hammer. They are NOT reverse threaded, but since they are facing the opposite way it is sort of backwards. You still need to turn the screw counter-clockwise or left to loosen the bolt, but since you are not facing it, you will actually be turning your wrench/ratchet to the right/clockwise... if that makes sense.

I tried some penetrating catalyst as well and even did it 12 hours beforehand to soak in and I still couldn't get it. I tried blowtorching it but eventually stripped the bolt and paid a mechanic $57 to take it off!!!!

My advice is rachet with a really tight socket and hit it with a hammer. Don't use a wrench or you will strip it!!! Good luck!!!

[rzm3]

How long of a wrench/ratchet are you using?

[1984M3]

Thanks guys for the suggestions. I was using a 6'' socket to try and loosen them. I also tried beating the handle of the socket with a hammer to loosen with no success. I went to the hardware store and got a 12'' breaker bar to see if that will help along with pb blaster. I've seen pb blaster mentioned previously on the forum. I guess if I'm not successful tonight, I will have to break down and have a local shop install it.

[ThunderMoose]

I had to use my breaker bar

[edwinm3]

Breaker bar is your friend...never never neeeeever hit a ratchet with a hammer

[BMW Fanatic]

+1 on the break bar if they're not coming out willfully.

[bluecusion]

use long breaker bar should help you break it loose easy

[rzm3]

Originally Posted by m31984

Thanks guys for the suggestions. I was using a 6'' socket to try and loosen them. I also tried beating the handle of the socket with a hammer to loosen with no success. I went to the hardware store and got a 12'' breaker bar to see if that will help along with pb blaster. I've seen pb blaster mentioned previously on the forum. I guess if I'm not successful tonight, I will have to break down and have a local shop install it.

6" is way too short. Let us know how the breaker bar works out!

[kaiv]

If you don't have an impact:

PB Blaster + Breaker bar

[1984M3]

Breaker bar and pb blaster did the trick. Thanks again for everyone's help. Got the passenger rear on but ran into a clearance issue with my wheel, Morr vs8.2. The caliper mounting bolts just touch the surface to create a circular mark on the inside barrel. Upset to say the least when these are suppose to clear the 380mm kit. I saw swamp had a similar issue with his RACs. Should I grind down the heads, look for alternate bolts with smaller heads, or worse case get new wheels?

[M3PO]

Originally Posted by m31984

Breaker bar and pb blaster did the trick. Thanks again for everyone's help. Got the passenger rear on but ran into a clearance issue with my wheel, Morr vs8.2. The caliper mounting bolts just touch the surface to create a circular mark on the inside barrel. Upset to say the least when these are suppose to clear the 380mm kit. I saw swamp had a similar issue with his RACs. Should I grind down the heads, look for alternate bolts with smaller heads, or worse case get new wheels?

I never like the idea of grinding fasteners on brakes. Also, you may be able to gain enough clearance through grinding when the brakes are cool or used lightly but keep in mind that you may still have the same issue due to thermal expansion if you use the brakes aggressively.

I think getting new wheels is the only right way to do this. That's what I would do.

[1984M3]

[QUOTE=M3PO;12630071]I never like the idea of grinding fasteners on brakes. Also, you may be able to gain enough clearance through grinding when the brakes are cool or used lightly but keep in mind that you may still have the same issue due to thermal expansion if you use the brakes aggressively.

I think getting new wheels is the only right way to do this. That's what I would do.[/

I don't like the idea of grinding them either. And I might get hit again with thermal expansion during aggressive braking.. I saw on m3forum that a member did grind the fasteners to clear a set of 18s for tracking with no issues. However, that just may be a lucky case where nothing bad happened. I'm just wondering what swamp did in his case with the RACs, if he switched them out or if the light marking on the inner barrel eventually went away. I've got to make a decision here shortly.

[Brucewonder]

breaker bar is your friend!!!

[M3PO]

Originally Posted by m31984

I don't like the idea of grinding them either. And I might get hit again with thermal expansion during aggressive braking.. I saw on m3forum that a member did grind the fasteners to clear a set of 18s for tracking with no issues. However, that just may be a lucky case where nothing bad happened. I'm just wondering what swamp did in his case with the RACs, if he switched them out or if the light marking on the inner barrel eventually went away. I've got to make a decision here shortly.

Have you tried PMing him? I think you are right, one data does not a trend make. The bolts will eventually "clearance" themselves by gouging out the aluminum on the wheel so I don't think it's a good idea to just let it "go away". It could weaken the wheel barrel and create a perfect failure point.

[1984M3]

Originally Posted by M3PO

Have you tried PMing him? I think you are right, one data does not a trend make. The bolts will eventually "clearance" themselves by gouging out the aluminum on the wheel so I don't think it's a good idea to just let it "go away". It could weaken the wheel barrel and create a perfect failure point.

I'm going to pm swamp now. Appreciate your advice and input on this. I also contacted Morr about this. I'm waiting on their input about the situation as well.

[1984M3]

Got swamp's input on this and received a response from Morr. Per Morr, this wheel will only fit brembo 345 to 365mm in the rear. Looks like I will need to make a change.

Thanks again to everyone for your help with this.