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For what it is worth, when I have had a bad MC seal, the pedal sank slowly with medium/firm foot pressure (engine running). When it was air in the system, the pedal went down quickly (engine also running).

If you are feeling even (steady) resistance throughout the pedal travel, I would guess a MC internal seal. If there is no resistance or a songy feeling, I would guess air. A spongy feeling would probably start with almost no resistance and then gradually become a little firmer near the bottom of your foot travel. You might get a "bouncy" feel with air in the lines.
I get the feeling that you are fairly confident that the air is out of the system, so my best guess is that your new MC is bad.
 

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Discussion Starter #42
There's virtually no resistance to the pedal with engine running. It goes down quickly. Nearly as light an effort as the clutch pedal. I didn't take it right to the floor, but if I pressed hard enough, it would get just about there.

With engine off, it's not rock-solid, but much firmer, nearly normal.
 

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Bob, still sounds like air based on your last description. :frusty:

I tried skim reading the older posts in this thread. One thing (for the future) that I would not recommend is opening all 4 bleeders at the same time. That opens the possibility for air to enter the lines.

If you plan on re-bleeding, put your E-brake on so that the rear shoes are up against the drums and the rear cylinders are as full as they can be. That's less fluid that gets displaced when pressing the pedal. With dual MC chambers you don't get quite the stroke volume as you did with the old (1960's) single chamber MC's. I'd start at the right rear, then left rear, right front, left front. Watch the fluid level in MC closely. You might want to start by having the pedal pushed a few times and while keeping it pushed, top off the MC and re-cap. If there is a lot of air in the system, it will compress and that fluid in the MC will drop quickly. Make sure you are using a bleeder canister that has the pipe that goes to the bottom and submersed in fluifd so that you can't possibly suck air back in when the pedal is raised (except what still might be left in the plastic tube, and those bubbles should be dispelled with each stroke).

Speed bleeders are also a big help.
http://www.speedbleeder.com/install.htm

Worse case, you might have to take this to a garage where they power bleed the system.
 

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Discussion Starter #44
What you describe, except topping it off with the pedal depressed, is exactly the way I've always done it. Last time I just goofed by working 2 wheels before checking the fluid.
 

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Discussion Starter #45
SUCCESS!

Just bled all four wheels. The RR let out a lot of air, LR very little, RF a fair amount, and LF almost none. Topped off between each wheel.

Pedal felt rock hard. Started it up, and it felt pretty much like normal. Rolled it and they grabbed, nicely. Test-drove it a couple of miles cautiously, got gas for the first time in 3 months. Someone there asked me what year my Dodge Daytona was (!). We had a good talk, although he said his was a '99. My wife, upon being told, said, "They had the Avenger then instead, didn't they?" What a great MoPar wife!

Drove home, and it felt like it used to - average. I was hoping it would feel better than ever, but my Turbo brakes far better than the '93. So it's just about the same as it's always been - a little mushy, but stops fine, and nose-dives when I hit the brakes hard.

I'm going to let it sit the rest of the week and do one more bleed all-around, just to make SURE all the air is out and it can't get better than it was when I bought it. But for all intents and purposes, it is FIXED.

Big thanks to all who contributed.
 

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Good deal! Success cancels out frustration again. :)
(been there many times)
 
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