I seem to have been steadily losing my rear brake (pushing the pedel down more and more with less brake). There was still about 1/8 inch of pad left but I changed them anyway. Here is the problem. When I try and pump the brake preasure up to bleed it, nothing happens. I open the valve and fluid dribbles out with NO air bubbles but the brake still won't pump up. Any ideas.
Oh, no leakes in the system that I can see.

 

I've noticed on a couple of raptors that the pins that the caliper slides on will start to seize. That will cause a problem like that. Bad master cyl. will also do that.

 

The pins seemed to be alright except they have a little corosion on the m that I need to clean up. Also the plunger seems a little stiff. But that wouldn't cause the pedel not to pump up. Maybe it's the master cylinder. Is there any way to test it or just get a new one and see what happens.

 

If the system is properly bled and your not getting pressure and/or volume out of it that's the only thing left.
You could disconnect the line to the master and see if you can bleed it and get any pressure to eliminate everything else.

 

sixsixT,
Thanks for the info. I'll give it a try.

 

Mines did the same thing and I had someone pump the brakes about 3 times and then hold it down on the last one and then I open the bleeder and just a drop came out, then I closed the the bleeder and had them pump the brakes again doing the same thing of holding it down on the last pump and after about 20 times repeating this it finally built up enough pressure to get bleed properly, just make sure you watch the reservoir and keep it full.

 

THats right....don't give up on bleeding the rear brake....it takes a while too pump up.

 

I have seen em with air way up in the master cylinder and line stock with only a few hours on them.. Keep bleeding, take a tube from the bleeder all the way back to the reseviour and keep at it. It may take 20 times