Can't Bleed the Brakes

[FY1Cuda]

I'm sure this has come up before, but here goes.  New master cylinder, new brake lines, original proportioning valve and metering block.  Didn't bench bleed the MC (when I've done that before, the bench becomes a toxic super-fund site). Pumping the brakes with a rear bleeder open did nothing.  Leaving it overnight with a rear bleeder open did nothing.  Borrowed a brake bleeder suction device today and tried it on the both rear wheels.  The compressor was getting hot after twenty minutes, but brake fluid wasn't getting back to the wheels.  Tried the suction bleeder on the front left--nothing.  When I pump the brakes, I kinda think the fluid in the front smaller reservoir raises, but then settles down to the original level.  Pretty sure the booster rod is set the right length (just missing the piston).
Any thoughts?

[anlauto]

You didn't bench bleed the master, but did you at least bleed the master in the car first BEFORE hooking up any lines ? This is a must

[burdar]

On my car, I bench bled the master first.  Then I installed it on the car and left ALL the bleeders open.  I also left the cap off the master.  Within 10 minutes of letting it sit like that, I had fluid at all four wheels.

It sounds like you might have a problem with the prop valve.  I'd loosen or remove the "output" lines from it and see if you have fluid there.  Only have the two master cylinder lines hooked up to it.  My guess is that you don't have any flow through the valve.(valves depending on year)  Someone sells a seal kit to rebuild the old style brass valves.  Did you take yours apart to clean/rebuild it?

[GreenFish]

Yeah, I would unhook you lines and bleed the master

[roadman5312]

You didn't bench bleed the master, but did you at least bleed the master in the car first BEFORE hooking up any lines ? This is a must

                                          If ya don't bleed the master you will never stop.  The kit that comes with the master makes it easy, fittings, clear tubes, its a cinche. 

[FY1Cuda]

You guys are fast! I guess you've shamed me into bleeding the master.  I don't have the kit but I can rig something up.  I didn't do anything to the brass valves except clean them up.  Thanks for the quick responses.

[anlauto]

I saved a pair of old master cylinder brake lines, just cut them shorter and looped them back into the master...works great....

YOU HAVE TO BLEED THE MASTER

[FY1Cuda]

Just came back from the parts store with a MC bleeder kit--fittings, plastic lines, clips.  Hooked it up, pumped the brake pedal 20x. My wife, the official observer, said there was one drip into the larger rear reservoir and nothing into the front.

[burdar]

You need to hold the hoses IN the fluid. If they aren't IN the fluid, you're sucking in air every time you let off the pedal. Also, take the master off the car and bleed it on the bench. I don't think you'll get all the air out of it otherwise.

[FY1Cuda]

 Thanks. Replaced the original black plastic lines from the kit with clear ones and dunked the ends into the fluid in the reservoirs.  Pumping the brakes gets fluid and air into the large reservoir.  Nothing happening in the front smaller reservoir. Will bench bleeding work any better?

[burdar]

You can push the piston in farther on the bench. Press the piston in nice and slow...not fast.

[Falbz]

I had the same exact problem with 3-4 "new" master cylinders.  Is this the 1970 style one most commonly sold.  Centric brakes?  I'd personal toss that one if it is and go get any auto parts one.  I like oreily's brake best one personally.  Just double check bore and make sure the same.

The problem is the second piston is not pushing fluid - faulty master 

But as everyone said I would always bench bleed before installing    if you do not see fluid pushing into that smaller front resovoir it has nothing to do with proportioning valves / metering valves yet. Good luck

[CudamanTom]

The crowd chants... "bench, bench, bench".

When it comes to stopping a car, do not bypass important steps. 

Your (and passengers) life depends on it.

[Falbz]

And don't worry I thought I was losing it myself when this happened and got nothing bench bleeding 3/4 new masters 

[FY1Cuda]

OK.  I heard you guys.  I took it off and put it in the vice, but already I could see something different than when I put it in.  Before I installed it three months ago, the piston stuck out from  the rear a little.  When I removed it, the piston wants to stay in part of the way.  I can pull the piston back out, but it doesn't do it by itself.  I tried the bench bleeding and the front reservoir did nothing.  I'm bringing it back right now.  Here are pictures of when I got it (piston out) and now (piston in)