At work today I thought I would get paid and change my front discs at the same time

I did the near side no probs, as I've done them plenty of times. Then I got on to the off side, I undid the top bolt of the Brembo caliper no probs, but the bottom one was tight as hell. So I undid it bits at a time while spraying lube on it, so it didn't get too hot and snap etc.

Eventually the bolt came out, but it also brought the threads of the caliper out with it Luckily I could Heli-Coil it and get home. I also had to use a Stainless Steel bolt.......

Now, is it safe? The heli-coil was done correctly, but can I keep using it safely? I will change the stainless bolt as obviously stainless is brittle.

 

I think this is more common than you may think, I have had one of my Brembo calipers done, about 4 years and 50-60k miles ago. No probs so far.

 

did the same to mine when i had the brembos on,never had a problem with them at all after that.if the helicoil was done well then there shouldnt be any probs.

 

I did the heli-coil myself, but have done 100's of them at work, so I'm confident in the workmanship.

Glad it will be ok. Thanks for the replies!!

 

The braking loading on the caliper bolt would be a shear force, the helicoil will be fine imho.
I would however get a new bolt.

dipster

 

Yes, helicoil is fine but replace SS bolt, I think OE bolt is 8.8 tensile strength. Stainless is softer than carbon steel at normal operating temps. Tighten to 75 ft-lb, manual says 113 ft-lb but this is excessive.

 

Nice one, cheers guys I had to use a S/S bolt to get me away, as I was changing my discs at work when the threads stripped, and we only use stainless bolts (and everything) due to being a food factory. I have asked my mate to get me a bolt from his place of work

 

I had three done on my old set of brembo's as said the thread stripping seems to be a problem on the gold brembo's.

 

I replaced the discs on the rear of my STi and one bolt just wouldn't come out, finally shearing. Luckily, I drilled out the remains and was able to clean the (a bit damaged) thread with an M10 tap. All went back ok but with less torque applied on that one!
I've heard of bolts sticking in these calipers!

JohnD

 

There are loads of people who have helicoiled or timeserted their Brembo's.
I think Brembo/FHI screwed up on this one, or at least cut some corners cost-wise.
Looks like FHI wanted a name brand caliper on the STI, as an upgrade.
These Brembo caliper bear the name, but are not up to real Brembo specs

Galvanic corrosion can easily occur, and the Alloy caliper is always going to come up short against a steel 8.8 bolt.

 

In my case there was definitely a defective bolt (front caliper). It hadn't been machined properly and had a lump on the end of the thread but still got murdered in at the factory, obviously tore the alloy of the caliper to pieces when I forced it out.

 

Mine were helicoiled when I bought them off a guy at Subaru. He states there was a problem with them being over-tightened at the factory.

With that in mind, I always thought it only happened on he first time the bolt has been removed, but the OP states he has done it loads of time.

 

Might also be dissimilar metals causing a bit of corrosion making siezure more likely. I assemble caliper bolts with medium loctite thread lock (blue lipstick version available in Halfords). This is easy enough to undo when required and seals the threads against corrosion, never had any problems after using this stuff.

 

ive had my brembos done and they seem fine , and they get used if you know what i mean

did you recieve the bits for the wheels chris ?

 

ive had my brembos done and they seem fine , and they get used if you know what i mean

did you recieve the bits for the wheels chris ?

 

Yes thanks, I thought I'd PM'd when they came. Sorry for not!

Glad the helicoil is nice and safe then does anyone have any high tensile M12x1.75 bolts I could have please? Well, not bolts, just bolt.


Cheers

 

no worries chap

 

Had an issue with one of my brembo rears just drilled it and tapped a new oversize thread rather than use a helicoil

 

Perhaps a stupid question but i take it the helicoil still requires drilling prior to installment?

 

Yeah, you drill the knackered hole, tap it, then screw the heli-coil in.

 

He did mine as well !

LOL

dunx

P.S. Ev* Brembo bolts use a coarser thread and aren't prone to this problem... unless Godspeed tell you the wrong spec.

 

this seems a common problem on the scooobys, the evo has the same ish brembo caliper but they never seem to have this issue,,,, seems strange i have the same issue on my mrs's car so its looking like a helicoil

craig

 

Yeah Dunx if only I was as perfect as you I made a mistake once giving out the wrong thread pitch !

The Subaru has An M12 x 1.5mm pitch , and the EVO has an M12 x 1.75mm pitch on the front calipers.

Both cars rear calipers have M10 x 1.5mm threads though

It can be a problem with both cars calipers though , we get quite a few in to helicoil , we are set up to do either the mounting lug threads , or the inlet , pipe and nipple threads which are all M10 x 1mm threads

Cheers Ian
01656 723060

 

You may aspire to my lofty heights...

dunx

P.S. My tame MOT tester builds loads of big BHP Ev*s and he's done about two in the last three years... but lost count on Subaru failures.

 

Coarser threads are there for a reason: to take bigger torque loads without failure and not to seize as easily.

 

To add , if I have any of these calipers to recondition and 2 or 3 threads are not perfect , I will helicoil them all to an M12 x 1.75mm thread and supply new bolts to suit.

So if anyone wants that doing give me a shout.