Ateca VZ3 - Drilled Discs - Holes blocked!

[Bahnstormer_vRS]

I have a conundrum.

I've had my Ateca VZ3 for a little over two months now and covered 1,750 miles a lot of which is stop/start and short journeys, having bought it at 6 months / 4,000 miles old i.e. total mileage approaching 6,000.

I've kind of got used to the brakes, Brembo calipers with 370mm drilled discs, being a little bit screechy when braking gently i.e. when creeping forwards in slow traffic, and that the pads appear to be 'high dust' .

What I was not prepared for is the (brake) dust getting into and blocking up the drilled cooling holes in the discs.

My conundrum is two fold;

1. Is this issue typical or is it perhaps a legacy of the initial 4,000 miles when I suspect the car may have been driven hard (it was owned by Cupra UK), and

2. How best can I get the drilled holes unblocked?

For #2 I'm thinking of cleaning the holes by using, say, a 3.5mm drill bit (the holes seem to be 4mm) that's long enough to go through both discs or maybe punching the holes clean with a suitable, 6", nail.

Any other suggestions, knowledge or experience?

Guy

 

[SRGTD]

I’ve just done an internet search on ‘holes in drilled brake discs clogged with brake dust; is this normal?’ and it seems it is normal - reported on a number of other car forums by owners of performance cars fitted with drilled discs.

Try the above search - or similar search - as there are various suggestions on removing the accumulated brake dust. It’s also suggested on some forums that not clearing the holes of brake dust deposits can inhibit cooling of the discs, which can lead to micro fractures around the drilled holes with certain types of use. Probably more of an issue with activities such as track days if the brakes (whatever disc type) aren’t cooled down sufficiently after heavy use.

 

[Bahnstormer_vRS]

@SRGTD - Indeed.

I did my research on the Interweb last night, after starting this topic/thread and have also, a few days ago, got advice from a very close McLaren & Porsche owning friend.

This is not a new problems with reports of 'drilled discs getting clogged' on PistonHeads and a Porsche Forum from circa twenty years ago.

The consensus opinion to rectify, is to drill out the clag with a hand drill using a bit slightly smaller than the holes, precautionarily wearing a mask (I've got some of those left over from COVID days), but do not use a jet wash or compressed air.

I guess what I'm more interested to learn is, are other CUPRA VZ, owners not limited to Ateca but Leon & Formentor too, similarly afflicted in our lowly steeds (compared to high performance cars)?

Guy

 

[TheSwede]

Try compressed air if it bothers you. I have the same discs on my Leon Cupra, I don't care so much about this particular "problem" , has no effect on the cooling I guess.
Several holes on my discs are also blocked.
Common regarding drilled discs.

 

[Bahnstormer_vRS]

@TheSwede - Thanks for your suggestion.

I doubt that compressed air will work, certainly not at this stage to clear the compacted brake dust in the holes; which I can't poke out with a wooden pin or drill bit. Besides I haven't got access to a compressor, without going to a garage and using their tyre inflator.

As to the effect on cooling; I'm sure there will be a detrimental effect if the holes are blocked; if not, why have them in the first place.


Guy

 

[TheSwede]

Main function I believe is to clear away gases and debris during hard track use. Cooling…very tiny holes, very little air through them.

They can cause cracks, which is not good at all.

 

[TheSwede]

PS For a regular street car, the holes are more of a decoration.