# Brake Question



## Wilma (May 3, 2015)

I have a 1968 GTO Convertible with power brakes. My understanding (from hearing this years ago) is that the brakes are still supposed to work in a manual mode if the engine is not running, it's just that the pedal effort will be much higher. Well, mine don't work at all in that scenario. You can mash the brake pedal for all you're worth and the car will still keep rolling. I've replaced all of the brake lines and wheel cylinders and as long as the car is running the brakes work fine. The only thing I can think of is the master cylinder, but what could be wrong there that would prevent the brakes from working when the booster isn't running? Any ideas are welcome. Thanks!


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