Brake fluid not flowing from the reservoir to the brake lines - can't bleed brakes!!!

[2.7turbo]

1998 Audi A4 2.8Q

I had to replace the right front caliper because it was fully extended and would not retract (pads down to zero)... After that was all set I tried to bleed the brakes. When I hook up the vacuum line I can't draw any brake fluid through the reservoir. The cap on the reservoir is off, and there is plenty of fluid in it. I can pump the brakes with the bleeder open and the reservoir full and nothing will come through the bleeder. I tried the rear brake and same thing - with the reservoir full and cap off I put 30in hg of vacuum on the bleeder (yes bleeder is open) and the vacuum will stay but nothing flows through. Does this sound like a Master cylinder issue?

I removed the master cylinder last night - I could not get fluid to from the reservoir through the master cylinder... The operation on the master cylinder feels normal.

[2.7turbo]

Updated the notes. Anyone?

[cervantes559]

try closing the bleader pump the brakes a few times till gets hard open the bleeder or a bit close it pump the brakes and repeat it a few times i did that when i replaced my rear rotors and pads and after a few times brake fluid eventually came out..

[Seerlah]

You are using a vacuum through the bleed nipple and not a power bleeder from the reservoir, correct? Not sure if you have access to one (don't want you to spend money on something that only might work), but I would try a power bleeder at the reservoir. If fluid enters the reservoir, then you should be good to go. Keeping it at low pressure will ensure you don't crack the reservoir. If fluid doesn't enter, at least you canceled out one variable.

[mysman]

Yep, it's possible on a 14 year old master cylinder that pumping the pedal all the way to the floor could have damaged the internal seals. It's one reason why people use power bleeders.