No brake fluid is getting to my rear drum brakes.

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dodgemahal

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I'm restoring a 1973 Dart Custom. It sat for many years, during which, the master leaked and I had to replace that. Should I suspect the proportioning valve? Did the valve trip that shuts off half the system. In this case the rear half. Is there a way to test/inspect the prop valve? Thanks for any help.
 
Is the brake warning light connected and working? If the spool valve is stuck at one end, that light should be on when the key is on.
 
I did bench bleed the MC.
I connected a 12V test light to the switch terminal to perform that test. I did NOT light up. I do not have the front calipers connected to the MC------for now I've got a plug in the rear MC port.
 
The test would be to ground that wire on the valve to see if the circuit is complete and the warning light in the dash comes on when you turn the ignition switch to the on position. The switch on the proportioning valve just grounds that wire if it's spool valve moves to either end.
 
cudamark said:
The test would be to ground that wire on the valve to see if the circuit is complete and the warning light in the dash comes on when you turn the ignition switch to the on position. The switch on the proportioning valve just grounds that wire if it's spool valve moves to either end.
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Good suggestion, I'll give that a try.
 
What I did was connect the clip of my test light to the battery positive and touched the switch post with the key on. No light on the tester.
 
That will tell you that the switch terminal isn't grounded, but, doesn't tell you anything about the rest of the system.
 
The switch closes the circuit and illuminates the brake lamp on the dash, per Cudamark, indicating the circuit has continuity. My test shows that the spool has not moved, closing said circuit. Correct?? This still doesn't get me any closer as to why there's no fluid getting to the rear wheel cylinders.
 
dodgemahal said:
The switch closes the circuit and illuminates the brake lamp on the dash, per Cudamark, indicating the circuit has continuity. My test shows that the spool has not moved, closing said circuit. Correct?? This still doesn't get me any closer as to why there's no fluid getting to the rear wheel cylinders.
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You'll just have work from where you have fluid flow to where you don't. Crack the line at the master cylinder and see of it pumps out there. Then try the output side of the proportioning valve. If it flows into the valve, but, not out, there's a blockage in the valve.
 
cudamark said:
That will tell you that the switch terminal isn't grounded, but, doesn't tell you anything about the rest of the system.
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Cudamark, I didn't see this post until after I wrote my last post. I think we're on the same page. Thanks for your guidance.
I agree with you on tracking the flow, and I started that process; unfortunately my flare nut wrenches suck. I started to round off the hex on the tube nut outlet going to the rear brakes. I need to upgrade from my ebay sourced, Chinese junk. Any recommendations there?
 
dodgemahal said:
Cudamark, I didn't see this post until after I wrote my last post. I think we're on the same page. Thanks for your guidance.
I agree with you on tracking the flow, and I started that process; unfortunately my flare nut wrenches suck. I started to round off the hex on the tube nut outlet going to the rear brakes. I need to upgrade from my ebay sourced, Chinese junk. Any recommendations there?
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I think Snap-on makes the best ones, but, they're very expensive. Mac, Craftsman, Proto, SK (are they still around?) Are decent too if can find some good used U.S. versions.
 
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