Brake Issues!!
 

I had a caliper hang up on me a couple weeks ago so I ordered two new calipers and new pads. I prefilled them (just filled them up with brake fluid) and installed them along with the pads. Then I bled them and bled them and bled them and bled them probably 1/2 gallon or more of brake fluid (i have a mity vac pump and I also had someone pump the pedal). My problem is that I can pump them up and they'll hold but as soon as you take your foot off the pedal it loses it's pressure and you have to pump them up again. So I changed the master cylinder (bench bled it first), same thing. Don't know where to go from here, any help???? Thanks. Coach.

Have to ask...are you bleeding the rear brakes first then the fronts? If yes then, have you inspected the rear cylinders? Pull the rubber boots back on the rear cylinder and check for fluid.

Speed Bleeders are nice for one person bleeding. I used the MityVac for years but the constant pumping required was tiresome!

Did you bench bleed the master correctly?
http://www.cardone.com/english/club/...es/Bleeder.asp

http://autorepair.about.com/od/fixit...ench-bleed.htm

I didn't attempt to bleed the rears at all, I had assumed that the pedal should have gotten firm on the fronts alone especially since its the larger reservoir. I did bench bleed the master according to the instructions which matched the links that you had attached, however it never became so firm that I couldn't move the piston. I should mention that until I replaced the calipers my pedal was firm all the time so I didn't even look at the rears and also there is no fluid leakage anywhere. The mity vac is a PIA to pump sometimes, wrists get sore. Thanks. Coach

Which method did you use to bleed the master, 1st or second link? I use the 2nd method (finger tips over the ports). Either way it's easy to fail to remove all the bubbles, you really need to not hurry bleeding the master and allow the air bubbles to rise then excape. Sounds to me like you will need to remove the master cylinder, re bench bleed it then bleed your brakes (rear first).
Good Luck!

I used the plugs and did bleed the rear brake part of the master. I also used my mity-vac on both front and rear. I did notice that when the piston is pushed, the rear brake had a nice shot of fluid shoot up, I didn't see that at all on the front brake portion. Thanks for the input. coach

well I figured it out and I feel really stupid, I put the calipers on per the parts guy telling me which was right and left, turns out he was wrong. Swapped sides and it bled up right away, back on the road after two weeks!!!

Always remember the bleeder screw should point up.

Thanks, I'm always going to remember that from now on! Coach