Drilling out brake disc retaining screw - but what next?

[wemorgan]

Today I changed my car's brake discs and pads. But I had to drill out the disc retaining screws as even an impact hammer would not remove them.

I didn't anticipate this happening so I had no replacement. So I just refitted with new parts minus the screw.

But I would like to replace the screw before too long, as I need new tyres soon and the garage wont that me for allowing the discs to rotate when fitting the wheel.

I drilled out most of the old screw and obvious enough of the head for it to release the disc. But inside the thread I can clearly see some of it remaining.

Do I just need to retap the thread and fit the new screw? Or is there another method.

Thanks for any advice.

 

[renault12ts]

Will, is the disc not held on by the wheel? There really isn't any danger of the disc coming off.

 

[wemorgan]

Yes you're right the disc is being held on by the wheel nuts. The only problem is that when I next take off the wheels the disc is free to rotate, so aligning up the bolts to the holes is less than trivial. It's more to get things right and proper, than anything else.

 

[renault12ts]

A tap will probably help to clean out the thread if it's just the threads which are clogged by the remains of the old screw.

 

[wemorgan]

From what I could see it was a bit more than just a bit of waste material in the thread. It's more like the inside of the hole is completely smooth with the remnants of the screw.

 

[renault12ts]

Then a slightly bigger drill bit until you just start to reveal the threads.

 

[jaymanek]

I would start with a tiny drill bit and move up until you get near the thread.. then its a matter of tapping through.

 

[khimani_mohiki]

Shouldnt there be a pin which locates the disc as well as the screw?

 

[BlackC55]

nope!

 

[Cen]

I recently had the same proble with the wife'd MX5 and drilled a small hole for which I then used a screw extractor and the bolt came out clean.

Obviously the bolt was now no longer usaable so a quick visit to screwfix solved the problem. It was a Sunday therefore main dealer was closed to get original. Screwfix sell a good quality tapered head bolt with an allen key fixing rather than the phillips head on the original. I am guessing the allen key head will be much easier for future removal.

Good luck, the wheel will hold on for now manufacturers often have a floating disc usually on rear discs