Tricky Technical Problem!!Removing Seized Caliper Carrier Bolts. Ideas Please!!!

[s2dude]

ok guys.
So I got to stripping down the brakes to fit new disks and pads a couple of days ago...
Was expecting an 2 hour job in total including cleaning up the calipers and slides etc and getting the car running again...

But No.....it couldnt be that simple!!!
Some dufus who owned the car previously (or a mechanic who worked on it) had rounded the 17mm bolts that hold the Front Brake Caliper Carriers on......

So my nearly new 17mm Britool socket just turned on it when I gave it any effort...
not good and to cut a long story short I managed to presuade one bolt from either side to come out..the top ones as it happens.

I looked at it a few days ago with Bry and Andyp and the consensus was to cut the bolt heads off as precisely as possible so I could waggle the disc and persuade the carrier off that way. Then take the disc off and work out how the hell I would get the remaing 80% of a very highly torqued bolt out of the mounting braket that the lower bolts fasten into....

pictures below highlight the work done and problemn Im now faced with
The Carrier WOULD not pull back away form the disc enough to allow me to slide it out of the bolt hole (the remaing half bolt anyway)
and the disc wont come off either ....leaving me a big problemo....!!!

Im looking for if anyones ever had rouned caliper carrier bolts before and what the heck they did ....also ideas on the best way to move forward......
see more text in next post

Starting



Tricky access (ended up having to rotate the guard..dodgy..)



After LOTS of cutting and grinding (cuttting is a major PITA because the bolt is skirted you cannot get all the way to the back of the bolt head meaning more grinding being super careful not to grind the Casting that it bolts through!!



Getting there



The problem now is getting the bolt cut back flush to the casting so it can slide through freely ...without grinding up the casting!!

[s2dude]

Was able to mushroom the last bit of the bolt head meaning I didnt even skim the housing luckily



The current situation.....tthe disc will not come off even with one bolt out and some play in the other one...the clearance form carrier to disc is too slim for this




So basically...I see it as I have a few choices....none of them too enticing at the minute...

I could cut the caliper carrier off (and have to source a second hand one if anyone has one they want to sell cheap??!!) to get easier access to teh bolt.
Remove disc and try and extract the bolt using a variety of possible ways probably having to drill it and retap or use a helicoil insert in the thread.

OR//

I could just try and drill it with it all in situ (bit tricky as its so awkward to drill layed under the car) and once drilled....remove all the bits and helicoil the thread (most likely option)

OR//

I could just buy a big brake kit but still have to tap drill and helicoil that damn thread,

OR//

How the hell can I get the bolt out otherwise??????
All ideas appreciated as this is turning into a mare and I still have to get the other side off....though theres NO WAY I will cut that bolt...but will try and grind the flats back on to the 17mm bolt and downsize it to a 16mm or 15mm even....(wished I had thought of this first and I would have
done it on this side!!! I've even got the 4 new bolts to go back on the car!!!

OR// I will get a mate to weld a 17mm socket on to the bolt and will then use my breaker bar on it and bin the £3 halfords socket......(THE BEST WAY IMHO if it will weld to it ok)

[s2driveruk]

tried soaking it in anti seize or applying a bit of heat etc?

Personally i'd use a bit of brute force and smack the remaining bolts with a heavy hammer to see if you can break the corrosion free a bit - then they might turn

For the ones u cut the heads off not sure u have much choice other than to drill out and retap

Pain in the *** the S2 sometimes isnt it.......good luck!

[newsh]

What a PITA!

I think I would get drilling, making sure you stay central on whats left of the bolt, go for about 5mm, then try a stud extractor, easy out etc, just dont snap it off in the bolt, easy does it.. but first soak with Plus Gas and use a little heat..

On the other side use heat first, heat is your freind, weld something to the bolt or try one of those strange bolt extractor things that cuts into the head of the bolt?

There have to be quite a few people round here with callipers and carriers left over from monoblock conversions, if you need one let me know and I'll try and find one.

[newsh]

Yes wallop them with a hammer straight on the head, it may break the corrosion.

[newsh]

When you fit the new ones use threadlock, it keeps the corrosion out. Actually I always use copper slip but some people don't like it..

[s2dude]

When you fit the new ones use threadlock, it keeps the corrosion out. Actually I always use copper slip but some people don't like it..

Thanks for the posts and info guys.....

yeah. will use copperslip.....I dont have problem with it


I tried hammering it,......and also impact driver with 17mm bit.....
and I hit it HARD
Nothing....

but I think the main problem is that the nut is rounded so the socket just cannot get a grip...and is turning before the real torque is applied.

These bolts are normally Veeery tight anyway so I think your right and drilling is my only option ;(

Whats the plus gas stuff?? and will it damage the threaded casting if I heat it up do you guys think? or should it be normal when it cools and not distorted?

Also.....I will have to borrow a good drill as mine is crap!! but I will defo start small bit and work up.....

I know of some bolt removers that are drilled in anti clockwise....is this what you refer to with the stud extractor?? and I know I cant snap it or Im really in the mire!!!!! As it would never drill out

Problem is I have to keep the thread the same size if I want to use the audi bolts so isnt my only option a helicoil for this??

Surely if I drill out to the required 12mm then tap it...what will the thread size be??


Cheers

[s2dude]

any more input folks?

[Jon441cc]

What a PITA!

I think I would get drilling, making sure you stay central on whats left of the bolt, go for about 5mm, then try a stud extractor, easy out etc, just dont snap it off in the bolt, easy does it.. but first soak with Plus Gas and use a little heat..

On the other side use heat first, heat is your freind, weld something to the bolt or try one of those strange bolt extractor things that cuts into the head of the bolt?

There have to be quite a few people round here with callipers and carriers left over from monoblock conversions, if you need one let me know and I'll try and find one.

I second the stud extractor method how about welding a nut
then using a socket & 1/2 inch breaker bar ... and give some teddy

[s2dude]

I second the stud extractor method how about welding a nut
then using a socket & 1/2 inch breaker bar ... and give some teddy

Cheers m8
ive just ordered a stud extractor off the bay...should be here tuesday I hope
Hopefully that will do it.....

Otherwise am very keen on the welding idea but I flogged my turbo mig about 5 years ago stupidly so i need to find someone friendly and local with a welder

[90quattrocoupe]

Personally, I don't like stud extractors. I have had too many snap off. Even if you have to hire a person with person with portable welder, I would weld the nut on. Get the highest grade nut in the size you need, put it on the stud and weld the center. This will give you a better torque for pulling the stud, than any extractor will.

If you do end up having to destroy the carrier or screw up the hubcarrier, I would replace the hubcarrier with a used one. I wouldn't use a helicoil on a brake mount. You don't need an S2 carrier, any coupe will fit. Just use your hub.

Just my two pence.

Greg W.

[peteV6TDI]

if you look at the brake disc there are vent holes near the bit that sits on the hub, give the bit in the middle of the holes a good bang with a ball pin hammer this will crack the disc and the hub part shuld break off, then the rest of the disc will come off, then slide the pad holder back this will leave you the rest of the bolt to mole grip out

[Alistair C]

I've heard great things about these:





EBAY LINK

similar items available from snap-on at huge expense!

[HPmuirt]

Wow, never seen those bolt grippers before...they look quite good. I have never used the stud extractors, but I have seen others use them with a mixture of success and failure.

Personally I would go for loads of oil on the threads, then a large hammer to shock the rusty threads, then follow 90quattrocoupe's nut welding routine as that has saved me on several occasions. Welding the centre of the nut means that you can apply huge torque to what was a completely flush stud. Make sure the thread has cooled after the welding, or apply head to the casting.

Cheers n

Si

[s2dude]

Jeez..What a mare!! Job Done //not recommended!!

Thanks for the info guys.....see pics

THis is what I ended up having to do!!!!!
I was very keen not to have to drill the bolt and then wreck teh thread and possibly lower part of the suspension which Im told is very hard to get hold of???

@petev6tdi.....
I think it would take a LOT to smash one of these disks IMHO as it took some unreal cutting and grinding to get through it...a hammer made not even a dent??!

Anyway...in the order I did the beast