Brake failure!
 

Hello all. Today was eventful. I've changed the wheels on my car today and then went off to drive and I have no resistance in the brake pedal and it's hardly working.
I know the previous owner had a problem with the brakes before but I thought it was a bit of a coincidence its happened straight after changing my wheels.
There are no obvious leaks at all.
Bit confused. Any help would be great.
Thanks Joe

Do you know the nature of the previous owner's 'problem', what symptoms he had, with the brakes on your car, Joe? If not, could you ask him? It might give you a clue as to where to start looking.

I agree with you that the problem manifesting itself after changing the wheels is likely to be co-incidental. I'd be very surprised if simply changing your wheels could itself cause a problem with your brakes.

As you know, your car has a triangular split dual system, so even if one circuit went down, you should still have 80% braking effort remaining.

If it is a complete failure, I'd first check my fluid level. If that's OK, possibly air in the system, a fault in the master cylinder affecting both circuits, or a fault with the servo could all contribute to the symptoms that you describe.

There are members with a wealth of specialist knowledge on the 2 series who will be able to offer you more detailed advice, but the general principles are the same for most braking systems. At least it might give you a starting point and enable you to rule certain things out.

Good luck! Regards, John.

Thankyou very much for that. Yeah I'm aware of the issues previously but they were working perfectly up until I changed the wheels.
Very odd. No immediate signs of a leak and the brake fluid hasn't drained. I'll have to take the wheels off tomorrow and have a closer look to see if I've knocked a brake pipe loose or something. Pretty sure I didn't though. I will hopefully find out more tomorrow.
Thanks ever so much for the reply.
All the best
Joe

I have had a similar experience in the past but nothing to do with changing the wheels and it takes a few miles to set in. The Girling calipers were never fitted with return springs (on mine at least) instead relying on asymetric seals to retract the piston slightly when brake pressure is released. Trouble is that as they age the pistons can get stuck leaving the brake lining in contact with the disc. With foot off the brake there is no noticeable braking effect but there is enough contact for the caliper to run hot. Eventually the brake fluid boils and you get vapour in the system with the effect being just like air bubbles - complete loss of braking and foot goes right down to the floor. If this is your problem diagnosis is easy. Any offending wheels hub will be very hot to the touch.