bleeding
See if something from this trouble shooting guide helps.
http://www.classicperform.com/TechBo...oubleshoot.htm
This site has a good troubleshooting methodology.
kdf
The Best of Corvette for Corvette Enthusiasts
. My brakes aren't power assisted. Could that make a difference or is there some other factor from one car to another?
I'll never bleed any other way.





i am a big fan of vacuum bleeders and have used then extensively and succesfully ....except for Corvettes!!!!!!!! i agree with 62fuelie and get the pressure bleeder
"I replaced all four hoses and the steel lines on my TAs. I also had all four calipers off and lost most of the fluid from them and the master cylinder as well. I was able to bleed my brakes with the press the pedal, loosen the bleeder, tighten the bleeder, release the pedal procedure with no problems. It took about 15 minutes with a helper and my brakes work great. I read here all the time here about guys having to use pressure or vacuum bleeders . My brakes aren't power assisted. Could that make a difference or is there some other factor from one car to another? "
This guy can turn a wrench too... IMOP
"I did my front brakes one year and my rear brakes the following year. Others on the forum recommended the gravity bleed system. It couldn't have been easier. Brakes work perfect.
I'll never bleed any other way."
Here's some more food for thought... based on the assumption of no pedal pressure...
If your bleeding technique is sound consider looking closely at your master cylinder.
1) You may have let the fluid drop down to (below) the ports inside the chamber.... and if so you need to "bench bleed" the M/C.
2) If your M/C is old, when you open any part of the system that allows the M/C plunger to travel further than it's "normal" depth (and you push it in), the "old" seals ride across any rust or deposits in the bore. This usually pushes the envelope on the seals and they fail.
3) If your switch (aka prop valve) is actually working properly (most are not) it will slide internally to block your bleeding efforts and must be re-centered before you can bleed. In that case, I bleed one front & one rear simultaneously so the switch won't catch me again. I have disassembled & tested several of these switches to test that theory. But since you have no pedal, this is not really a suspect.... just worth mentioning.
Just a couple of possibilities.
Any of the bleeding methods mentioned above will work if executed properly. It's a personal preference. I can use any of them successfully.
Mine kept pushing air out both front caliper bleeders as I was bleeding away....had me scratching my head. I capped everything off one at a time and split the lines at every junction....all was fine. Checked the proportioning valve.....
Turned out that my caliper piston seals were sucking air back in as I was bleeding on both front calipers. I tightened everything up, thinking I was going to have to replace those seals later.....gravity bled the system....and the pedal came back to life, just as it should be. I know this is wierd......but that's what finally worked for me. Can't beat that gravity bleeding, I guess.
jd
The vac pump will also work if you are careful not to over-do it. Too much vac and it draws air in past the piston inner seals, defeating the purpose. It has to be used with some moderation.
And... I've never tested this... but pressure bleeders -supposedly- can introduce air into the fluid... supposedly the pressure which forces the fluid also forces air into the fluid. A correctly designed pressure bleeder is supposed to have a bladder between the outside air & the fluid to prevent this.
The pressure bleeders I have used were all "professional" grade, so I can't debate that issue. IMOP the cheapies will still work reasonably well.
The key is "patience". If you can't modulate your instant gratification curve, none of the methods will work.
Stand up, walk away from your computer NOW and go and buy one, alternatively stay at your computer and order one online. Ok, ok, ok they are not that earth shatteringly brilliant but they are by far and away the best, most consistent way of bleeding brake systems.
Cosmicvette
You think you have fun with brakes, try bleeding a hydaulic clutch. We have a small block in the back of a Fiero and had to bleed the whole system. If you follow any / all of the shop manual procedures, you never get the air out and either shoot yourself or stumble onto a different procedure that requires you to remove the bleeder fitting on the slave completely, hand pull the slave rod to get bubbles to come out, continually refill the port where the bleeder screws in until pulling the slave doesn't show any bubbles and then replace the bleeder screw.
Sounds stupid, but works.
Daffy
I will never go back to the old way of bleeding Corvette Brakes again. Took me no more then a half hour to hook up and have all calipers bled. Best pedal I ever had in my 73'.
A word of advice though. If you purchase the Motive Bleeder for early GM vehicles don't use the chain and J-hooks supplied by Motive to hold the Master Cylinder Adapter on to the Master Cylinder. Cut yourself a 6" piece of 1"x2" scrap wood and put that accross the adapter and use two 6" C-Clamps to secure the adapter to the master Cylinder and you will have a complete seal. The chain and J-hook setup supplied by Motive has caused problems with getting the adapter to seal properly. This has happened to plenty of members on the C-2 forum but a C-2 member there came up with the solution that I have described.
A word of advice though. If you purchase the Motive Bleeder for early GM vehicles don't use the chain and J-hooks supplied by Motive to hold the Master Cylinder Adapter on to the Master Cylinder. Cut yourself a 6" piece of 1"x2" scrap wood and put that accross the adapter and use two 6" C-Clamps to secure the adapter to the master Cylinder and you will have a complete seal. The chain and J-hook setup supplied by Motive has caused problems with getting the adapter to seal properly. This has happened to plenty of members on the C-2 forum but a C-2 member there came up with the solution that I have described.










