I'm currently trying to upgrade my rear brakes and so far have managed to remove the calliper and one of the carrier bolts but the other is in a bit of a mess.

When trying to loosen it, the wrench slipped and I have managed to mangle the opening of the nut...

Looks all ok inside but I can't get the attachment to sit all the way in, so my initial thought was to bang on the wrench attachment, re-gouging the hole and giving me the purchase needed, but I don't have enough room the generate the power. :(

Was wondering if anyone has any bright ideas?!

mole grips / water pump pliers to crack it ?
weld a nut on end?

Heat it up with gas and get mole grips on it? Doesn't look too bad

Knock it round with a long chisel.

put it all back as was and forget about upgrading

I've got some water pump pliers I can try.... no heat gun yet, but on the list.

 

If I can get past the opening, it does look ok in there, but I just can't bang it hard enough :(

put it all back as was and forget about upgrading

I'm upgrading as the O/S calliper is goosed :(

Hi

Had the same experience the other day. Mole grips did it for me. Heat is a good idea too.

Part number for new bolt - N 90740302

Alan

Try a torx ot "star" bit see of that will do it if you've already rounded it off, if not sharp chisel and tap it around

Well I've packed up for the evening now after giving the mole grips a go but couldn't get enough purchase, but I will be back at it again tomorrow.

 

Cheers for all the input so far.

H&S tip for leverage work in a confined space:  heavy work gloves (gardening gloves at least), for when the b****r slips

Take the disc off and press the tool into place using a clamp or vise-grip, once pressed in, gently heat the casting, apply a squirt of penetrating fluid, tap around the area, undo, profit.

 

Repair the bolt by peening the burred end over with a ball-pein hammer and hammer the tool in until consistently shaped, refit.

Can you get a dremel in and take the head off?

I have a mapp gas blowtorch you can try mate. 

Also have a small cordless impact driver which may be able to 

crack it undone. I'll catch you tomorrow.

Irwin sockets usually do the job, hammer one on and it'll grip the bolt.

 

http://www.screwfix.com/p/irwin-bolt-grip-nut-remover-set-5-pieces/96028

Dremel: don't own one yet, but can get my hands on one if I need. Will look tomorrow afternoon once I'm done elsewhere.

I need to get one of those sets in my kit Fordfan, look pretty good.

Yes Garry, that would be awesome. Cheers mate

Hacksaw blade and run in a line across the head. Then you can use a flat blade screw driver.

I was going to say what Matt H said but he beat me to it. Good luck, hope you get it sorted.

And yes those Irwin sockets do look good too.

Not got a stubby drill?

Get some penetrating oil on it asap - but NOT on disc or pads!

Not got a stubby drill?

No :( Borrowed a posh blow torch today and will give that a bash

Get some penetrating oil on it asap - but NOT on disc or pads!

All bolts were pre-soaked with it, just this one is more stubborn than me that's all

What I would do before doing any of the above is bash it really hard with a club hammer and a drift, normally this will shock the fastening and it will reshape the head of the bolt, you may even be able to use a proper Allen key socket in it still.

I've got the proper Allen key socket (I was using it when this happened), only have a claw hammer or a rubber mallet and not sure what a drift is? Kinda new at this

Use your hammer, not the claw side obviously... hit it hard, repeatedly. Then it will just wind out..