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

 

Damn, glad y'all are safe.

 

Scary... I have a 71 alfa spider which has a problem with the master cylinder. Some times the brake pedal hit the floor! Ive since had the cylinder fully rebuilt (rebored) and I now have a solid pedal... lets hope it lasts..... I yours single system?

 

Hi,

I had the same problem with my Lamborghini Urraco a few years ago, brakes were completely overhauled / partly brandnew and all of a sudden.... no more brakes at all, pedal to the metal. We found lots of air in the system but no fluid loss. I went almost out of ideas but my mechanic said it could ONLY be the master cylinder, Lambo used BONALDI brand master brake cylinders and the seals although they were brandnew obviously did not seal at anytime, anyway the design of the seals is not good engineerd.

So he gave me the tip to change the seals against ATE seals and after a time of research in catalogs I have found seals which fitted the BONALDI cylinder and no more issues since.

Check if your Fiat has a BONALDI mbc and try ATE seals, probably it helps you.

Regards, Joachim

 

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

 

I will share my two cents on this, First, I have had at least 10 Fiat/Bertone X1/9's over the years and even more 850 based cars, and I will tell you that the clutch and brake masters fail. The only luck I ever had in replacing them is with OEM stuff. The stuff at the auto parts stores do not work on these cars. The ones made in Italy are the only way to go. If you don't use OEM, then you are asking for trouble. Most of the non-OEM clutch masters don't work right out of the box.

The seals will leak through the bore, and then you have nothing, when the seal swells, it works again.
Seen it, don't like it, try to avoid it………

Change it out, there are many dealers that can sell you the right part.
Now back to your regular program………

On the Ferrari, I get the brake fluid changed regularly, as I don't even want to go looking for a abs master cylinder for the 328………...

 

Any way to fit a high quality aftermarket master?