The booster itself cant go bad can it? It has to be the seals inside?

 

When the diaphram seal inside goes, so to goes the power brake booster. I haven't seen a rebuild kit for the booster. You can send your old booster out as a core exchange or simply buy a new one for about $150.00. Or..... go HydroBoost.

 

Thanks

 

I will be buying a power brake booster today for my brother's car. It needs a lot of work. It seems the previous owner gutted the parking brake system.

After taking the calipers off of the rear to inspect the parking brake, the system needed bled. Then the bleeder valve was rusted and removal cracked the caliper threads for it, so the caliper had to be replaced. Then I was getting no good pressure at the bleeder valves or brake pedal. The system squirted fine out of all bleeder valves, but didn't have any pressure especially on the rear pads. I could push the pistons back by hand as the pedal was depressed.

So I replaced the brake master cylinder for $20 and one caliper and still no good pressure in the pedal and it still went to the floor. There are no leaks in the system anywhere. It just seems under load the hydrolic squirt is not strong enough to squeeze the pads correctly which first lead me to believe that the master cylinder was leaking back on itself and it was cheap enough to just replace.

Now it seems the power brake booster's diaphram must be leaking and not having enough pressure to push the mc's piston. It's $100 for a new one.

Other than that the only other part that it could be that I can see would be the combination valve.

Also the brake light remains on which I believe will go off once the pressure returns.

Then it has a hesitation problem, brake light problem, rotten leaf spring bushings. I can go on and on, but one thing at a time. Sorry to hijack this post one my first one. Hope to see more of this forum and members. I like corvettes, who doesn't, but I drive a civic Si. The corvette pulls harder.

Thanks and any direction is appreciated in my troubleshooting or process.

Jason

 

Yes, but boosters seldom completely fail. They do get incorrectly blamed for other brake problems.

 

You need to replace the rubber 'jumper' brake hoses at each caliper. The ones on that car are probably disintegrated inside and are essentially "plugged-up" with gunk/dissolved rubber. That can be a dangerous situation that can keep brake pads partially applied. Can you say "Brake Fire"?