under floor brake wil never bleed..any ideas?

Doing the same thing and expecting a different result OS a pretty good definition of insanity and a really good description of what you are doing.

Start isolating components.
Start with the master.
It's all been said at least once & I can't add anything but a pep talk.

 

If you have drum brakes on the back, adjust them so they are rubbing on the drums and then try again.

 

always remember "just because the parts are labeled new doesn't mean they are good" The part is only as good as the QC person that did or didn't check them.

 

Clear vinyl tubing on each end of the car attached tightly to the bleeders and hung all the way to ceiling is a cheapo way to bleed a difficult system. Slightly Crack the bleeders and push gently as necessary. Air is gonna to find it's way up the tubing. You can stick it into water bottles or whatever on the high side. Used this method on 200 MPH formula cars for years if the pedal felt spongy

Be careful though and don't push it out onto your nice shiny paint

 

I am totally confused by the combination of your posts and would like to clear up the confusion. So do you have the residual pressure valves or not?

I was under the understanding of the first post saying "you need to find out if they are built in or needed?" meaning that you dont have any installed, because you were under the assumption that they may be built into the master cylinder, correct?

Did you install some after the first post, and not say so, or did you always have them, and just wanted to make sure you weren't having 2 sets of Residual valves on the car, or what?

Brian

 

Brian, Always had them i just switched the rear valve to disc when I did the rear disc swap.I just wanted to make shure there was not already built into the wilwood..its not so Im all set there.
I tryed the clear plastic tube thing..no air.
I had the wife psh on the pedal and crack where the lines bolt on at the master and some aire came out and it got much better so I repeated and re blead everything..but same thing after i let it sit.
So it is doing the same thing after.
1. 1st build 7 years ago. under floor master booster,diac front drum rear, residue and rear prop valve and line lock..all new lines.
2 same after swaping to rear disc and changing to the disc valve.
3 finding a pinced braided lines in front and replacing..thought that would be the cause.
4 swaping the corvette master wilwood master
5 bleading it and checking everything over and over and over..
I am going to plug the master and see if it does the same then follow it to each brake there is got to be a solution.

 

Are you running a presser type brake switch? I can’t remember the exact reason but a friend had a similar problem and it was the brake switch. it was a fresh build all new...

 

If you are getting air out of the system every time you bleed it you have a leak some where.I know you are not seeing a fluid leak but that doesnt mean you dont have an air leak on the return stroke.

 

"I am going to plug the master and see if it does the same then follow it to each brake there is got to be a solution."
This was suggested on page 2, post #29, many moons ago! Happy hunting............... <!-- / message -->

 

10-4 brigrat

 

Thanks. I dont think I even need to block lines.
I think air is getting into the front.
The brake pressure(line lock) might be the cause..it has never really been used because I have a trans brake . It is a cheap summit line lock.
I will bypass it and see what happens..

 

A buddy had problem bleading clutch on a Ranger and we had to take mounting bolt off master cylinder and bleed it with the front facing up to get the air out of it?

 

Uuuuuuu, well you left the line lock part out for days over these 4 pages.
Any chance that line lock was installed oooohhhh 5 years ago; right about tge same exact time your system started acting up ???

 

What you need to do is re-bleed the master with the plastic tubes supplied with the kit. Route the tubes back into the reservoir and submerge the ends in brake fluid as the fluid goes both ways when pumping. Pushing the pedal pushes fluid and air out, releasing the pedal pulls fluid in. They have to be submerged to pick up fluid on pedal release. This is an important step and you will never have a solid pedal until it is done. The MC must be level or all the air will not evacuate. Pump gently until air stops appearing then reconnect the brake lines and re-bleed at each wheel. My Wilwood MC would not work properly until I leveled the MC and bled it using this method.

 

I have a smaller version of this system http://www.kd-tools.com/products4.html that I bought back in 1977 and it will bleed/flush any system you can imagine as long as you can make or buy an adapter for the master cylinder. Mine is more portable (size of a 1 gallon paint can) and has a 3 foot hose that attaches to the adapter via Milton fitting. I haven't encountered a system yet that it wouldn't bleed. You put fluid in the tank, seal it, add 5-7 psi then go to the farthest wheel and start bleeding. It adds fluid and bleeds at the same time.