Rear Brake Fluid Intake Problem

[sfrligo]

1994 K75

Realized last week my rear brake had leaked dry. Hooked up the MightyVac, put some fluid in the reservoir, and started pumping. Got lots of air, a little bit of fluid, but the level in the reservoir barely went down: fluid wasn't getting pulled into the line. I tried bleeding at caliper and ABS both, and tried combinations of pumping the foot pedal while toggling the bleeder open/closed.

Has anyone had similar issues? Any advice on how to find the leak/check whether it's the master cylinder plunger/get more fluid into the system?

Thanks!
Seth

[Inge K.]

Sounds to me that the smallest port from the reservoir is blocked, or the pedal is wrong adjusted (it should
be a few mm play between the pedal and piston).

http://www.motobrick.com/index.php/topic,7738.msg54905.html#msg54905

[sfrligo]

Thanks for the suggestion. I haven't changed the pedal adjustment since it was working fine and was professionally adjusted. I'm pumping with the reservoir open, so it shouldn't be an issue with a hole being blocked, correct? The rear reservoir on mine is cylindrical, and just has one big hole going out the bottom. The pedal bottoms out, and pushes material through, but doesn't seem to suck any in...

-Seth

[Inge K.]

Maybe this link would make it easier:

http://www.k100-forum.com/t1301-brake-seizure#47349

[K1300S]

brake fluid doesn't evaporate.  if system was dry, it leaked out somewhere....find the leak.   there should be a wet spot somewhere.

[Brad-Man]

Roll the bike in flour...