Brakes squishy. Won't bleed any air.

[Schnot]

I changed the brake line going from the ABS block to the right front wheel. Went to bleed it and no air comes out. With the truck off, the pedal will get stiff like it should but as soon as you start the truck it will lose all pedal. I tried bleeding all the brakes starting at the rear and nothing but clean fluid come out.

Any idea? Im thinking it is from the power steering pump or ABS unit but Im not a brake expert.
Truck is a 2000 F550 7.3L.
Thanks.

[hydroman]

The brakes are a hydroboost system and are power assisted from the power stearing pump, but it is an independant system from the brake fluid though. Unless you got into that somehow it should not be an issue unless it is just coincidence. Are you power bleeding the brakes? Also I have always started from the front and worked to the back, that way any air in the lines will be ahead of the fluid from the master cylinder, although I believe most systems are seperate front from rear except at the proportioning valve. But not sure if they a common there either.