Hi All - started to get some vibration (not good ones!) from front of car under braking - feeling like warped disks etc. I remembered when I last did brakes and disks that I was unable do get the top caliper bolt tight...

Pulling it apart today and removing that bolt revealed that it was tight all the way undoing it and on inspection the thread in the caliper has definitely stripped.

Looking in this thread

http://www.fullfatrr.com/forum/topic21039....o+threaded

it appears that it's not uncommon and a bit more googling of brembo and threaded pulls up loads of things (mainly Subaru impreza).

Now I guess gold standard repair would be replace the caliper (~£500), but many of the threads above report good success with helicoiling to repair. On that basis that's probably what I'll try first - therefore just checking if anybody had done or had experience of doing it?

Main questions for me are...

a) What size helicoil 'kit' should I be getting (i.e. what size are the caliper nuts) - I think (!) M10?
b) Torque setting for the caliper bolt - says 275 Nm somewhere - anyone confirm.
c) Any other wisdom/tips and tricks!

Cheers

Jim

Yeah, just imagine driving down the road at 20mph past a school with a front calliper bolt in a helicoil, it went in OK and tightened up, but, just as you had to jump on the brakes as that 3 year old ran into the road, the helicoil gave way, you didn't lose all the brakes but that caliper moved and jammed so you lost breaking on that wheel, the car swung to one side and the side of your front wing hit the three year old's head.... 2 1/2 tons of FF at 5mph is still a lot of force.... If it hadn't jammed you would have missed the child by inches... now they have impounded your FF and found the repair, your insurance have decided your not covered..... etc etc....

Now tell me £500 is expensive....

Sorry to be so graphic but I see it time and again on forums, people trying to save a few quid on brakes....

It just doesn't make sense no matter how you look at it... Pete

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275 Nm?

That's a lot of torque on a small bolt = 203 ft lbs.

I'd expect it to break or strip. Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA

A timesert would be better than a helicoil. F1 teams used to fit them on brakes and so did Boeing on their aircraft brakes.

go for timesert

don't worry about the children a timesert will hold better that a normal tapped hole in aluminium alloy.

good luck

I would plump for Timesert over a Helicoil although more expensive they are more substantial.
As long as it's professionally installed then Timeserts are actually stronger than the original in alloy and a lot more durable as the original bolt will be fastening into steel instead of alloy.
Best to take it to a specialist thread repair/machinist shop and then ask them and get them to do it.

Thanks so far - looked at the time serts - they do look more robust...

Anybody happen to know for sure the size of the bolt - otherwise I'll wait and measure tonight!

Cheers

Jim

dingg1 wrote:

go for timesert

don't worry about the children a timesert will hold better that a normal tapped hole in aluminium alloy.

good luck

All measured - bolt is M12x1.5 next challenge is finding a time sert supplier. appears Wurth are UK distributor but only sell to trade. Does anybody know a stockist?

Also still looking for guidance on the torque setting for those bolts if anybody has guidance?

Cheers

Jim

have you thought, about contacting a brake caliper refurbisher, and letting them do the insert, it would at least have a sort of guaruntee. and they will have best equipment to do it. normally they would be doing the hydraulics, but probably have taps and sundries, to sort the rusty threads etc.

Jim_m_kidd wrote:

All measured - bolt is M12x1.5 next challenge is finding a time sert supplier. appears Wurth are UK distributor but only sell to trade. Does anybody know a stockist?

Also still looking for guidance on the torque setting for those bolts if anybody has guidance?

Cheers

Jim

Am sure there are engineers shops or hydraulic specialists who do this sort of work in their sleep for a fraction of the £500 for a new one !

Just to close this one out - when I inspected the calliper after removing it I noticed that the seals had started to degrade - slight bobbles in them so decided that I would look at a refurb so also ended up removing the other side as well. Found a refurb place and sent them off on Saturday afternoon. Just went for a mechanical refurb rather that repaint - I chose them as they specifically mentioned doing time sert repairs. Box arrived yesterday morning, repair done, new seals caps etc..

Didn't opt for painting, was an extra couple of days turnaround

Guy said that the seal bobbling was due to using copper paste on the rear of pads, copper holds the healt and melts the rubber of the seals, recommended not to use copper slip on the rear of the pads. Fitted yesterday all went together well and tested good.

Thanks for advice!

Cheers

Jim

Haylands wrote:

Yeah, just imagine driving down the road at 20mph past a school with a front calliper bolt in a helicoil, it went in OK and tightened up, but, just as you had to jump on the brakes as that 3 year old ran into the road, the helicoil gave way, you didn't lose all the brakes but that caliper moved and jammed so you lost breaking on that wheel, the car swung to one side and the side of your front wing hit the three year old's head.... 2 1/2 tons of FF at 5mph is still a lot of force.... If it hadn't jammed you would have missed the child by inches... now they have impounded your FF and found the repair, your insurance have decided your not covered..... etc etc....

Now tell me £500 is expensive....

Sorry to be so graphic but I see it time and again on forums, people trying to save a few quid on brakes....

It just doesn't make sense no matter how you look at it...

I know this is closed out but I'm confused by that torque setting - I did mine to 110nm or 81lb ft - I have no idea how I'd get 275nm on it! Can anybody confirm the correct number?