Brake problems, AGAIN/STILL

[sman]

Everyone who has driven my car complains about the brakes(ESPECIALLY DR Phil.....which always starts a corvette vs fbody argument, lol), and even after putting the vette brakes up front last year, im still not impressed. I took it to a local shop last year and they said they did not need to be bled, and work functioning properly..... For as long as I can remember, I havent had any stopping power till about half way down the pedal, and could push it completely down to the bottom with little to no effort. I have never had a car that does that. But on occasion, that is not the case, in a panic type scenario the brakes have a tendency to feel different, much more confident and I can easily set the ABS off. But I CAN still push the pedal all the way down. It was bled about a million times last year to no avail

I put it away last year and forgot about it with the house and all. Fast forward ->

I went around the block a weekend or 2 ago and when I got back I noticed the BRAKE light was on, played with the emergency brake for a minute to no avail, said the hell with it. Put it back in the barn and forgot about it.

A few days ago im out there and I notice the MC reservoir is completely empty.... I seen no signs of leakage at any of the calipers (fronts are new last year) and 1 of the backs is only 2 years old. Its all dry around the line lock as well as all the connections at the ABS block. Even the MC connections were dry.

What the hell is going on here???

I have replaced basically every bit of the brake system over the last 3 years and its never gotten better. One thing I have NEVER touched though, is the MC.

At this point im just assuming the master cylinder is bad and needs to be replaced. Is that the correct course of action at this point? Id hate to buy one and it not be the issue as they seem to be $100 plus locally.

Any and all info would be helpful, Ive fought this for years and these threads never seem to get very far.

[Fox Slaughter]

Two things.

Stock rubber lines?
Ever completely flush the system with new fluid?

Brake fluid is hygroscopic. It will absorb water. Brake fluid does not compress hence how the braking system works. Water on the other hand will compress.

Also for future reference when the Brake Light comes on it means there is a problem with the hydraulic system. Usually low fluid.

[1BADAIR]

pull the brake booster hose off and see if its wet inside. looks around the booster and even inside the car at the pedal rod

[sman]

Two things.

Stock rubber lines?
Ever completely flush the system with new fluid?

Brake fluid is hygroscopic. It will absorb water. Brake fluid does not compress hence how the braking system works. Water on the other hand will compress.

Also for future reference when the Brake Light comes on it means there is a problem with the hydraulic system. Usually low fluid.

Yes stock lines everywhere.

Yes. We ran 2 quarts through it the last time it was bled just to make sure there was nothing in there. Fluid was coming out crystal clear, not dirt, no bubbles no nothing.

I know the light comes on when the fluid is low, it had just never occurred to me as I usually drive with the e brake up one click to keep the auto headlights from working and Ive head that switch get stuck a million times thinking the brake was up when it wasnt, so I attributed it to that as ive never had any leaks on the car.

[sman]

pull the brake booster hose off and see if its wet inside. looks around the booster and even inside the car at the pedal rod

Hadnt thought of that, will the engine burn brake fluid? Will check it out tomorrow morning, its to crappy out and im not walking out there in the rain. :lazy:

[Fox Slaughter]

I know stock rubber lines will expand when they are old when you push the pedal down. Obviously that isn't where your fluid is going though. Could have something to do with the pedal going down though. Not sure.

[98blackbeauty]

Does sound like MC is leaking out the back, usually when this happens you see it coming out where the MC bolts to the vac boost. But could be sucking into engine through the vac. hose. if thats the case I would definately change your oil stat.

[2002Z4CSS]

Does sound like MC is leaking out the back, usually when this happens you see it coming out where the MC bolts to the vac boost. But could be sucking into engine through the vac. hose. if thats the case I would definately change your oil stat.

If no visible leaks, I would agree.

[bri2203]

yeap the master cylinder could be leaking into the brake booser.

[BP_Z28]

yeap the master cylinder could be leaking into the brake booser.

Exactly what happended with nh green Camaro when I was getting it ready for winter duty.

[sman]

Well first inagural post from the "barn pc" No visible leaks anywhere. None where it bolts to the booster, pulled the vac host off of the booster and its dry, and nothing inside the car either.....

[1999Black_Z28]

Well first inagural post from the "barn pc"

Nice, I may need to get one of those once I get a barn

[sman]

Ill hook you up when ya get there! Still waiting on the lifts, guess the guy had surgery or something, hoping to know tomorrow.

As far as my brakes go.... Thoughts opinions?

[meissen]

My only thought is that you still haven't posted pictures of the barn

[sman]

Frustrated tone of voice: I can now see that we are fighting 2 issues.

1. Possibly defective master cylinder, the brakes have been bad for a while, and kept getting worse. Installed vette brakes to try and rectify the issue, stopping was greatly improved but pedal still felt bad.

2. Found a leak. After MASHING on the pedal in the barn I found dripping coming from the driver front, I unfortunately do not yet have tools to even remove that wheel

Need to get more of my tools moved out here....