how can the master brake cylinder fail during a service?

[mactusc]

I took my car in for a 12k service..... brakes were working fine..I later get a call from the garage saying the master cylinder had gone, that they couldnt get any pressure to the rear brakes after changing the fluid ?.... mentioned something about the cylinder 'flipping round ' ?

has anyone heard of this sort of thing happening , it all sounds a bit strange to me and i feel a bit anoyed about picking up a bill for a replacement when it was working fine ...

appreciate any veiws or opinions
thx

[GreenV8S]

Yes, quite credible. When you bleed the brakes you push the master cylinder well beyond the normal travel, and this can damage the seal.

[trackcar]

Would be rare on something so recent, but as greenV8S says it certainly can happen when the pistons are pushed beyond their normal range of movement.

[ec1 eex]

Same similar happened to my car when it was in for it's 12,000 mile service. The service was being done at the factory in Blackpool at the time and they replaced it under warranty.

[mactusc]

thanks all.... !