Have you tried going through the troubleshooting section of the FSM?

Hi Steve   I have. And it all leads to air in system.   I've bled it multiple times and different techniques.  Stumped! 

Check the calipers. Make sure the bleed screws are at the top of the caliper. Sometimes people install them on the wrong side, and the bleed screws are down. That traps air to the point that it is difficult to impossible to purge.

Symptom of reaction disc falling out when changing master cylinder. Fairly common. Happened to me.

Pull master and push rod. Fish out rubber disc and glue on to end of rod and reinstall rod and master.

Not sure why from the factory the reaction disk is not better attached. I read the the FSM recommends a dab of grease to hold it on......no wonder it falls off so easily.....


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Thanks guys!   I will check for the reaction disk tomorrow.  

Hey guys,   the reaction disk was in place.   I tested the booster and check valve and bench bled the MC while I had it out.  Pressure bled system and still same thing.  I'm thinking I'm going to gravity bleed at every fitting of system this weekend.  It has to be air in system!  Right!?   I Really appreciate your suggestions,  thanks 

So did you check the orientation of the brake calipers?

Sorry Steve,  yes I did.  They are installed correctly.  Bleeders up

Is there any chance the rubber brake lines at the wheels are ballooning?

I don't think so because I've replaced the rubber hoses at each wheel.  But I will make sure.  

Reaction disk aside, are you sure you don’t have a hole in the booster diaphragm? Do you have any engine speed increase when you step on the pedal with it running?