What is going on with my brakes???

They are power.

I've replaced all four calipers, new rubber lines, new master cylinder. I bench bled the cylinder and all four calipers. My wife pumped the brake then stood on it. I then cracked a bleeder and got a jet of fluid. Closed the bleeder.

Then she pumped them again and stood on it. Cracked the bleeder again and fluid dribbled out. The pedal now goes to the floor.

The lines were all filled with fluid before thos and there was not a lot of air in there.

What am I doing wrong?

The car stops but not quickly, the pedal is mush and goes to the floor.

This is my 3rd time bleeding the entire system. it seems like every time I try to bleed one I get a good solid jet then nothing the next time.

HELP PLEASE???

 

There is still air in the system either the master cyl. or calipers. Do this
Bleeding sequence is:
MC
RR - inside
RR - outisde
LR - inside
LR - outside
RF
LF

Ideas:
1. Did you change the MC. If so did you readjust the pushrod length? Just asking.

2. Vette brakes can be a bear. If you use the foot pump do it slowly otherwise you can aerrate the fluid.

3. When you pump and bleed, crack the bleeder, let the persons foot go to the floor and hold it there until you close the bleeder. Then crack the bleeder and "burp" the caliper.

I had a nightmare with my 73. I came upon a tool that I use on all cars now. Instead of bleeding, I use the tool for reverse fluid injection - uinjecting fluid from the bleeders to the MC. Physics says air rises. Go to Phoenix systems web site and read the posts on their products and bleeding. Download thier manual and read it for some tips. Good luck.
Site : http://www.phxsyss.com/

 

phoenix,
I agree with the above "PUMP SLOWLY" and I would like to add try rapping the caliper with a rubber mallet before you open each one, sometimes it helps dislodge the air bubbles. I have even seen guys tip the rears up and bleed. Also if your rotors are no longer riveted to the hubs run two lug nuts on to each corner. ....redvetracr

 

I concur with the method posted as well. You do know there are two bleeders on the rear calipers - right?

 

the first thing I thought as I was reading your post was make sure you
are pumping the pedal SLOWLY....and bleed from the farthest caliper from the master cylinder working your way to the closest caliper to the master cylinder.
Good luck......take your time

Kevin




[Modified by ksems, 6:42 PM 3/31/2002]

 

I had the same problems with my brakes. After replacing every componany I got fed up with it, and took it to a mechanic. He told me I had a bad master booster. I can't think of how that makes much since, but on my bill, thats the only "part" the rest is laybor costs. So I guess he replaced that, then bled the brakes the right way.

Daniel

 

I just had to do my 79. The shop manual says Driver's rear inside, Driver's rear outside, pass rear inside, pass rear outside, driver's front, pass front. Do it very slowly. On the rear, you can mix the pump and gravity method. Do the gravity method. Be prepared to spend a couple of hours per caliper. Gravity bleed the driver's inside, driver's outside, pass inside, pass outside. Then try tapping the caliper and slowly pumping the system in order. The best way to insure that there is no air in the system is to plan on running 1 or 2 quart bottles of fluid through the system. I tried every other method. This one worked the best.

 

If bleeding using the slow pump method doesn't work, then I'd zero in on this part of your post:

If this really happened the way you describe it, and the SECOND time you went from jet to dribble, it sounds to me like you had a piece of something in the line (might have fallen in there when you were replacing all that stuff), and it got lodged in a restricted area - either the caliper itself or one of the distribution blocks.

Try bleeding the other calipers to see if they maintain the jet (they should) or go to a dribble, too. If all but the one keep jetting, your piece of whatever would be in that one circult. If they all dribble, you've got something in the line between MC and the pressure differential switch (that block on the frame near the front, on the driver's side), or possibly in the PDS itself.

And last, not to insult you but only because I've been bitten by the "duh monster" myself: you are replenishing the fluid in the MC when you bleed aren't you?

 

Thanks for the advice. Don't worry I don't take any comments as obvious. I've been burned by the dumb stuff too many times. ;)

I am replacing the fluid as necessary, I know that there are two bleeders on the rear and I was starting with the passenger side rear caliper.

What I wasn't doing:
1. I was bleeding the outside bleeder first
2. I was probably pumping too quickly

I do have the speed bleeders in, can I use them by leaving them open and pumping? I was using them as security and bleeding them conventionally.

How slow is slow to pumping the brakes up? I am getting fed up with this bleeding brakes stuff. :(

 

Good job!

Excellent! Not many people think to test each cylinder...not really much nead actually. Bench bleeding is mainly to detect plugged or otherwise faulty master cylinders...I've come across two in my life that wouldn't squirt fluid out of one of the outlets.

I hope this isn't the way you bleed the brakes...bleeding them means attaching a clear hose to the bleeder with the other end of the hose immersed in a small clear bottle, then opening the bleeder and keeping it open while pumping the brakes about 15 times (if you have power brakes then the engine needs to be running). Also, on the last pump the brake pedal should be held down while the bleeder is closed. This should continue until all the fluid coming out is clear and bubble free. If bubbles persist then there's a leak somewhere.

Somebody suggested gravity bleeding (again)...there's no such thing. "Gravity bleeding" is basically creating a leak in the system. Leaks in the system are what CAUSES air to get into the system. The physics involved is very basic. When you have fluid exiting a tube, there will be air entering the tube...that's what causes fluids to drip instead of stream out...air sneaks in behind the fluid and separates each droplet from the next. If you could constantly inject fluid at a high pressure on the other end of the tube then you could prevent the air from getting in, but I can't understand why people will go through the effort of trying to buy some expensive equipment when all they need is a clear hose and a clear bottle.

I think the best advice is to go to your local library and check out your state's Department of Motor Vehicles "Brake Inspection Handbook"...if they don't carry it then order it from the DMV like I did. That way you can learn all about this stuff from a source that you might consider more trusworthy than some guy named "Rockn-Roll"

 

gravity bleeding is far superior to any other method, at least for my 72. http://community.webtv.net/MATTGRU/BRAKES