QuestionQUESTION: On my 79 Corvette the brake pedal goes to the floor with the engine running. With the engine off I have good pedal. I have replaced the pads and calipers on the front, the master cylinder and bleed the lines over and over. I have tried also power bleeding the system. I was told by a mechanic that the booster is working but I am not positive of that fact. I have turned the rooters to remove any glaze from the rooters. When I drive the car, it will stop but not very fast. I will not do a panic stop of any kind especially with the pedal at or near the floor. Do I replace the booster, proportional valve or what is next step to try?
ANSWER: I honestly believe you have an adjustment problem. Let me know if this doesn't fix your problem.
You can try (see previous brake answers) putting your parking brake on and see if this doesn't fix or help your problem.
I believe what is wrong is your rear brake as SEVERELY out of adjustment. You need to first inspect them and then adjust them until your wheel won't make a full 3/4 revolution when you rotate it. Try this (do both rear) and see if it doesn't fix your problem.
If not, let me know
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QUESTION: How do you adjust rear disk brakes? There is no adjustment capability. The parking brake is part of the rotor for the disc brakes.
AnswerI guess I was a little confusing, used a little brake shoe terminology by habit. This is more of a check than an adjustment. Make sure you have bled the brakes in sequence (farthest from master cylinder, then next closest, etc). Then with the brake pedal depressed, try and move each wheel and see if some move others don't. See if applying parking brake makes a difference not just in the wheels it is applied to.
