[fabkat]

Hi folks,

Had abit of a nightmare getting off the inner hex bolt for brake disc change, eventually having to drill it out. The new ones i have do not fit the hub as they are larger, standard m8x14 and matches realoem for my car(f31 lci) I tried to take a rough measurement of the one i got out and its maybe 5 or 6mm. Any ideas?

[TurboWeasel]

Strange! Maybe your car has aftermarket bearing hubs on it as the new bolt is the correct one for F3x.

[Kendo67]

Do you want an M8 tap to enlarge the thread ?

Whereabouts in Glasgow are you ?

K

[Ennoch]

They look the same to me? Daft suggestion; have you left the rest of the thread in the hub still?

[Pond]

It is not essential to re-fit the retaining bolt. They are just that, to retain the disc with the wheel off.
Once the wheels are on they do nothing.
The wheel bolts will keep the disc in place securely and it is not an MOT failure. I have a Mini with 2 missing (for the same reason). They were torx head ones which are even worse to get out without mullering the heads. I couldn't be arsed to source 2 overpriced bolts for no good reason.

By the look of the pictures, someone had driven a screw with a much wider thread pitch into the hub so damaging the internal thread. Could be wrong!

[Ennoch]

Originally Posted by Pond

By the look of the pictures, someone had driven a screw with a much wider thread pitch into the hub so damaging the internal thread. Could be wrong!

That's the removal tool you use when you've drilled the core of the bolt out, it's got a reverse thread so as it tightens in it undoes the stuck stud. It looks like it's snapped the bolt off half way though in this case.

[fabkat]

Thanks for all the replies folks. After getting a good look at it again in better lighting conditions today there is indeed a small bit of the thread left that the extractor bolt never got, it looked like part of the hub thread but sorted now