View single post by edward_davis
 Posted: 06-02-2008 08:35 pm
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Joined: 07-06-2005
Location: Eugene, Oregon USA
Posts: 162
The reservoir is supposed to serve both circuits, so you just have to fill it full to the top.  In the original TR application, the MC is angled so that the top of the reservoir is level, and that's why it looks so goofy in the JH.  I've only seen one JH with the original MC, out of the ~30 or so that I've seen, so this TR unit must work fine.  I haven't had any problems with mine since installation.  IIRC, the rear reservoir feeds the front brakes, so it has to be larger to accomodate the greater change in volume as the disc pads wear and the caliper pistons move to accomodate them.  The pistons in the drums are much smaller diameter, so they won't need as much fluid when they auto-adjust.  And if you have the manual adjust drums, they don't use any fluid, since the adjustment is made on the other side from the pistons.  That's why the reservoirs are so different in size, I think.

To get the PDWA to shut off, you have to have one person release the bleeder while another applies firm pressure to the pedal.  When the light goes off, the pedal pusher must shout to the bleeder operator to close the screw, lest the switch go too far and illuminate the bulb again. In an ideal world, the PDWA would have a built-in return spring, so it would only go off while there was currently a pressure differential.  Not so: it simply records that there was a difference.  By opening the bleeder screw and applying pressure, you're trying to shuttle the little switch back to the middle, null, setting. 

I rebuilt my PDWA, you know, and it immediately started leaking out the electrical connector at the top.  So I did like Mark suggested so long ago, and I plugged it up with an appropriate bolt.  Now it doesn't leak and the light doesn't go off, either.  Eventually I'm going to do like Judson (I think?) suggested, and get the inside of the thing plugged up, so fluid can't leak across in the event of a failure.  I might even make all new stainless brake lines and get rid of the PDWA entirely.