Hi, I rebuilt the rear master cylinder and now the brake fluid is not passing through (you can see the fluid sitting in there in the unit)… so I’m seeking a greater understanding of how this is supposed to work because the supply port [H] is not clogged. The fluid needs to pass through the top part of the cylinder where the spring [A] is housed to reach the rest of the brake line but how is it going to do that when the primary cup [C] which sits flush against the inner wall and thereby blocks the fluid never descends lower than that supply port?
If you need a hint on how this is supposed to work… The diagram shows how things should look without any brake pressure applied. With the brake pressed the piston ** gets pushed up which compresses the spring [A]. The primary cup’s [C] position would be roughly where the line to the right of label F is. Things would seemingly make a lot more sense if the ports H and G were interchanged on the diagram but that’s not how it says that it should be… not that I could fix the part anyways.
Thanks in advance for any help in resolving my issue here!
I believe there should be a small hole in one of those two dimples (not in the center). It’s terribly small. I used a section of safety wire to clean the one on my BMW R100.
It didn’t occur to me that such a tiny hole (in the relief port) could affect the system the way I described but in case it is, I’ve cleaned it with a pin and plan to test the system again today.