@#$@%&@ 250R rear brakes - HELP!

[MyMistress86R]

OK...a few weeks ago, I discovered that my rear master cylinder needed rebuilt. I figured at that point, I might as well change the pads too.

Anyhoo...I got the MC rebuild kit and a new set of pads. The rebuild came first and went very well. Good action and no leaks apparent after 24 hours. I pulled the rear caliper off since it needed a good cleaning and the slide pins needed freed up and lubed. Everything seemed to go quite well here too.

Here's the problem...after nearly a whole pint of brake fluid used in bleeding the system, the caliper won't pump up. I've taken the fluid reservoir, all hoses, the master cylinder AGAIN and cleaned them all thoroughly. All passages are clear and during bleeding, fluid does come out of the bleeding nipple on the caliper. BUT, the system will not pump up. I cannot get the caliper the develop any pressure on the rotor.

I've spent around 6 hours working on this and am beyond fed up with it. The only other thing I can possibly imagine at this point is that maybe the pistons got locked up when I compressed them to make room for the new pads.

Does this sound reasonable? It's all I can figure can be the problem at this point. Any help is greatly appreciated...I NEED MY REAR BRAKES!!

[Howdy]

You probably have a air bubble in the master cylinder. I would remove the line from the master ( that goes to the caliper ) and bleed the master cylinder first. I keep my finger tightly over the hole and pump it until the brake fluid sprays every pump. Once you get it pumping properly, then hook up the line and bleed the line to the caliper. Then I do the caliper, and your done. Doing it this way will isolate the problem area.
If you can't get the master cylinder to pump, then you know your master is the problem.
Howdy

[MyMistress86R]

I'll keep that tip in mind Howdy. Thanx for the info...