Brakes suddenly got soft???

[Guest bastaad525]

Okay I'm stumped. I dont think there's a leak as the fluid level in the master cylinder hasn't gone down... but last night and today my brakes have gotten MUCH softer, for no apparent reason. It will fluctuate... sometimes they'll feel normal, then suddenly they'll be soft... then normal, then so soft I almost have to floor the pedal to stop the car. I'm going to try bleeding them, but I find it odd for air to get into the system without fluid leaking out. Also the inconsistency of it makes me think it's not air in the system

 

I would think it's the fluid getting hot from the turbo but it doesn't matter if I'm driving hard or just puttzing around. So, asides from bleeding the system, is there anything else I should check? Oh I'm running the bone stock 240 brakes.

[zguy95135]

the same thing happened to my sister's old bug. The brakes would go soft and there wouldnt be any fluid leaking. It turned out that the mastercylinder was leaking internally, and after that was replaced it was fine. Maybe you can rebuild it instead of replacing it for a quick fix

[JMortensen]

The old master cyl test:

 

Stab the pedal, let it up, then push really slow. If it works when you stab it and goes to the floor with the slow push, then your master is bad.

 

Jon

[Guest bastaad525]

Figures.... well I just bought this thing rebuilt about 1 1/2 years ago... and it had problems from the start, so I dont doubt it's gone bad already. Right after I installed it it developed this strange problem, it would keep somehow pushing the fluid from the rear 'bottle' (one closer to the firewall) to the front bottle... so much so that the front bottle would start overflowing and leaking all over the place. So every month or so I have to drain the front one and top off the rear one. Guess I shoulda done something about it then, huh?

 

Okay... so... new master cylinder added to the list of parts I need.