QuestionI have a 68 impala and the brakes are shot! I had brakes (all drum) rebuilt, new booster and master cylinder and it worked okay for a few months and now its back to the pedal hitting the floor and no pressure at all. I have not replaced the brake hoses or any other components other than I listed. when car is on and pedal hits the floor nothing pisses or makes noises so I doubt its the booster. Any suggestions?
AnswerIf you haven't already done this, check the fluid reservoir to see if you have fluid in there. If the fluid is full and you have no pedal, the master cylinder has failed.
If the fluid is low, fill it (both halves) and then pump the brake pedal about 20 times to see if you can get any pedal at all. If you do get the pedal to give you some resistance, stand on it and then check under the car to see if you can spot where the fluid is leaking out. Also, inspect the inside of each tire to see if there is any sign of fluid leaking down the tire from the middle.
If you can't find any sign of leakage, remove the vacuum hose that connects to the booster and smell the inside of the hose. If it smells like brake fluid, the booster has failed and is allowing the engine intake vacuum to suck the fluid out of the system.
On that old a car, you should have replaced the brake hoses (3 of them), and if you live in a rust prone area, you should also inspect the steel brake lines - one of them may have popped a rust hole and be squirting fluid out every time you step on the brakes. If you find that is happening, replace ALL the brake lines and hoses!
Dick
