I searched for awhile to try and find a post with the answer i need but didnt find anything so im gonna make one.

I have an 83 camaro z28 with a carbed 5.0 and the brakes dont work. When i first bought it, 2 or 3 months ago, it had a bad wheel cylinder but it still stopped. So i fixed that and it stopped but when i tried to get it inspected the guy said i needed new brakes all around it. So i replaced the rear drum brakes and the front disc brakes and then bled started to bleed it. I started with the rear drivers side, the side where i replaced the wheel cylinder. It bled normaly and so i went to the passenger rear then to the passenger front then to the driver front. When i got done with all that i got in the car, backed it up a little, it stopped but the pedal was soft until about half way, so i pulled it up and back a couple more times and then the whole pedal went soft. So i started to bleed it again startin at the driver rear again and barely any fluid would trickle out of the wheel cylinder but if i took the brake line off it poured out. So wondering if the others would do this i went around the car again in the same order and they were all fine, except the driver rear. So i bled it again and a little more came out. Then got back in the car and the pedal was still soft all the way down and didnt stop the car at all. So i took off the tires to see if the pads were even attempting to stop the car, the only ones that moved were the driver front and the passenger rear. The driver rear and passenger front didnt move at ALL when i pressed the brake. No idea whats wrong here. Someone told me the brake booster was bad and told me to "check it" by pumping the brake when its off, the pedals stiff when its off, so i press the brake down some then turn the car on and the pedal goes to the floor. Does this mean the boosters bad or the master cylinder or something else? And why does the wheel cylinder i replaced a couple months ago only let a tiny bit out when the almost 30 year old other one do its job?

Sorry for the extremely long post and sorry if it doesnt make much sense. Someone please help me out

 

I'm not sure, but the fact that the driver front and passenger rear work may say something. If I remember correctly, there are two somewhat separate circuits, cris-crossed, so that if there is a leak in one the other will still work for some time.

Have you checked your break fluid? Did you notice any leaks after pumping the breaks?

 

The brake fluid was slightly low after the bleeding so i topped it off and it didn't go down anymore.

 

so your saying the brakes pump hard and normal with the motor off and with the motor running the peddle goes to the floor?

 

I'm suspecting the master cylinder. A bad booster is not going to let the brake pedal drop to the floor, as that has nothing to do with the hydraulic pressure of the brake system (other than pushing the master). You're losing pressure in the line(s), either from trapped air or a bad seal in the master cylinder letting the fluid blow past. On rare occasions, a bad seal in a wheel cylinder or caliper can allow air to suck in on the back-stroke without it leaking fluid externally. I've had it happen, and it was a tail chaser. If and when you do replace the master cylinder, be sure to bench bleed it. The new m.c. will have the hose, fittings, and instructions on how to do it.

 

The brake pedal only goes to the floor when the cars on. I ordered a booster and itll be here later today but i went out and tried some more stuff. Someone said to open the master cylinder cap and press on the brake when the cars on/off. When the cars off and you press it, the fluid jumps into the air a tiny bit, it looks like when you drop something from about 5 inches and it lands in the water, that kind of plop, although nothing drops into it. When i turned the car on it and pressed the brake it did the same thing and the fluid didnt go down at all. Does that mean it isnt working? and if i close the cap and stomp on the brake you can hear what sounds like the booster sucking in air.

 

Got the power booster today and installed it, no more squishyness, all it needs now is another bleedin. Thanks for all the input guys, i appreciate it.

 

drinks for the house, meet in the lounge maro s payin.

 

Yay, hopefully you'll be able to find the rest of the air in the system, unless that's what jumped out of the open reservoir. Since you kept getting air out of the drivers rear, keep an eye on that one. If you bleed it again and you later have air at that same wheel, suspect something is wrong with the wheel cylinder. When you were bleeding the brakes before, you didn't drain the reservoir all the way before filling it again did you? I honestly can't see how a bad power booster can make the pedal go dead to the floor. There is a solid connection from the pedal, thru the booster, and to the master cylinder. The power booster assists the movement. Am I nuts somewhere? (no wise-cracks)!