2 Year Old Brake Master Failed.

Hi Folks, I'm posting in this section because I know many of you guys have done major rebuilds and have probably encountered some oddities in your time.
Firstly I'd like to say that we run 4 Italian vehicles, that's 2 Ferraris, a Fiat X19 1976 and a Ducati racer.
The question is partly a warning to others and a query, now before you all groan it actually relates to our beloved X19 and the reason for posting here is really to serve as a word of caution since it has made us revaluate the 2 Ferrari cars as a result.
2 years ago we overhauled all the brake calipers on the car and to be safe we replaced the master cylinder and hoses also. The car is ultra low miles and corrosion free it should be noted.
As a result we have had 2 years and 5000miles+ trouble free motoring. Then last night without any warning at all and I mean nothing.....Total brake failiure. One minute a good solid hard pedal and the next, foot to the floor nothing. Luckily we drive old performance cars and so Emily is well drilled for just such a problem and quickly applied the hand brake at a set of traffic lights that brought us safely to a stop.
So next thing brakes are back again like nothing had happened, needless to say we checked fluid and then limped home very slowly. On arriving the brakes failed again and on bleeding them we found the master cylinder had taken on lots of air.
My question is, has anyone ever known of this kind of master cylinder failiure.
There are no apparent leaks from it and importantly ther is no servo masking anything of drinking the fluid.
The fluid level was full as I say and no leaks from calipers or lines.
Any thoughts would be most welcome.
All the best Bell Bloke

 

Hi Guys, many thanks for your responses.
Hi Todd, yes it was damn lucky that it didn't happen on a steep hill, I mean brakes for god sake! This is not something you expect to totaly fail without warning after an overhaul 2/3 years ago.
However fail they did and I will so report back here with what I find + photographs etc also the make and model of the unit.
Hi Joachim, your story is most interesting, thankyou for posting, this sounds identicle to what's happened to us. Obviously the seals have gone I just need to see in what way they have failed and make a decision on where to purchase another unit. After this episode I will also be making sure that all are cars have excellant hand brakes.....
I know it's tempting to think on these occasions that it's 'operator error' but really it's not and that for me makes it all the more worrying because as I see it, it's a mojor componant failiure that could have had fatal consiquences.
Anyway I'll report back and if anyone else has a similar story to tell i'd be most interested.
All the best Bell