So this happened today...

Andrew J · Post by **Andrew J** » Fri Jul 04, 2025 6:47 pm

Blyton track day. Brakes failed and couldn't slow the car. Gutted to say the least.

Bombur · Post by **Bombur** » Fri Jul 04, 2025 7:09 pm

Firstly hope you are ok, secondly am gutted for you

Andrew J · Post by **Andrew J** » Fri Jul 04, 2025 7:14 pm

Thanks. Yeah was a bit of a shock to the system but not too bad now.

Rockhopper · Post by **Rockhopper** » Fri Jul 04, 2025 7:24 pm

Old brake fluid? Pedal went to the floor?

kis · Post by **kis** » Fri Jul 04, 2025 7:34 pm

Gutted for you.

How did it fail? Track day all the basics usually well taken care of?

Andrew J · Post by **Andrew J** » Fri Jul 04, 2025 7:42 pm

Rockhopper wrote: Fri Jul 04, 2025 7:24 pm Old brake fluid? Pedal went to the floor?

Could have been. Not sure when it was changed last. Yeah pretty much. Brakes faded on a previous run so came off and cooled them down for a while then went back out again.

kis wrote: Fri Jul 04, 2025 7:34 pm Gutted for you.

How did it fail? Track day all the basics usually well taken care of?

Yeah all fluids topped up, tyres pressures okay. Engine running sweet. Still runs now to be fair and it can move, just not well. I've just put on new brakes at the front too so not sure why it failed.

kis · Post by **kis** » Fri Jul 04, 2025 7:47 pm

Andrew J wrote: Fri Jul 04, 2025 7:42 pm
Rockhopper wrote: Fri Jul 04, 2025 7:24 pm Old brake fluid? Pedal went to the floor?
Could have been. Not sure when it was changed last. Yeah pretty much. Brakes faded on a previous run so came off and cooled them down for a while then went back out again.

kis wrote: Fri Jul 04, 2025 7:34 pm Gutted for you.

How did it fail? Track day all the basics usually well taken care of?
Yeah all fluids topped up, tyres pressures okay. Engine running sweet. Still runs now to be fair and it can move, just not well. I've just put on new brakes at the front too so not sure why it failed.

Yeah looks like the steering is pissed. Control arm damage?

Brakes just done. Did you run it for a bit? Bed the pads in? Ensure no air introduced in the system.

Andrew J · Post by **Andrew J** » Fri Jul 04, 2025 7:51 pm

kis wrote: Fri Jul 04, 2025 7:47 pm
Andrew J wrote: Fri Jul 04, 2025 7:42 pm
Rockhopper wrote: Fri Jul 04, 2025 7:24 pm Old brake fluid? Pedal went to the floor?
Could have been. Not sure when it was changed last. Yeah pretty much. Brakes faded on a previous run so came off and cooled them down for a while then went back out again.

kis wrote: Fri Jul 04, 2025 7:34 pm Gutted for you.

How did it fail? Track day all the basics usually well taken care of?
Yeah all fluids topped up, tyres pressures okay. Engine running sweet. Still runs now to be fair and it can move, just not well. I've just put on new brakes at the front too so not sure why it failed.
Yeah looks like the steering is pissed. Control arm damage?

Brakes just done. Did you run it for a bit? Bed the pads in? Ensure no air introduced in the system.

Yeah ran them for a bit. Have done a few miles on them. They were just normal pads so they didn't have a bedding in procedure. Bled them after too and had a decent pedal.

Joez4 · Post by **Joez4** » Fri Jul 04, 2025 10:02 pm

I'm no expert but when I changed my pads and discs I read online it takes about 500 miles of driving to bed brakes in and not to do any hard braking during that time as you can overheat the pads and glaze them, my guess tho is old fluid getting boiled

Rockhopper · Post by **Rockhopper** » Sat Jul 05, 2025 8:51 am

Usually if the pedal goes to the floor then that's boiled brake fluid. It'll come back when its cooled down. If the pedal goes hard but the brakes just don't work no matter how hard you press the pedal then that's overheated pads.

1536Z4 · Post by **1536Z4** » Sat Jul 05, 2025 10:32 am

Think of it this way at least it didn`t happen on the road and you and everyone else on the track is ok . Hope it doesn`t take too much to get it sorted .

damocell · Post by **damocell** » Sun Jul 06, 2025 8:58 am

Had my brakes totally fail on me at Donington in my Astra VXR due to bad cooling and boiled brake fluid. Very scary stuff. Glad you are ok mate.

Gotta change your fluid though and braided lines at the very least on the front are a good idea. Which make/model of pads were you running?

Perhaps consider joining the FB Z4 Track Day Group too, loads of good info in there on brakes: https://www.facebook.com/groups/520863040768702/

buzyg · Post by **buzyg** » Sun Jul 06, 2025 4:40 pm

Glad your ok. The car will fix.

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