proportioning valve choices

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andrewgasc

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as i was changing my front brake hoses and lines, upon trying to remove one of the front lines from the proportioning valve to my surprise one of the nuts broke in the valve. im now on the hunt for the correct valve for my application to replace this one, none of the local auto stores carry the valve, local chevy dealer told me its discontinued but gave me a part number, gm- 25515631, acdelco-172-1356. found a valve on summit for front disc, rear drum, https://www.summitracing.com/parts/sum-760186?rrec=true#overview looks the same, but from my searches gm made a wide variety of these valves functioning in different manners.

i guess my question is, where you all sourcing new proportioning valves for these trucks? and how are you ensuring its application correct?

(edit) I've also seen people mention a proportioning valve tool for bleeding brakes, was wondering if anyone could shed some light on that tool and its purpose.
 

Turbo4whl

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(edit) I've also seen people mention a proportioning valve tool for bleeding brakes, was wondering if anyone could shed some light on that tool and its purpose.
Their are 3 types. When you remove the rubber cover, if the pin looks like a nail head, the tool slips under the nail head and you roll it back and pull the pin out a little. (No picture) More common type, the pin is straight, (no Nail head). the tool is a little clamp that pushes the pin in. You may need two of these:

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The last tool, you pull out the tattle tale switch and install this tool. It keeps the valve from moving. I have never used this one. Not sure I trust it won't break off in the valve.

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Rusty Nail

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Ow man.
Gonna need pix.

See, there is a  pintle inside the valve flat moves from one side to the other. Ppl have issues with their prop valve because the pintle has gone to one side and hung, which it is designed to do, but only in failure, to maintain  some braking. Either front or back.
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The fix involves moving fhe pintle back to "free float" in the middle of the two.
I like eBay but it's not likely broke - prolly just the line. You'll have to open the other side and use brake fluid pressure to reset it after you fix the line.
If you replace the valve, that same issue remains. It's freaking Pandora's Box, blee dat!
But there is hope!
Gonna need pix.
Cuz hat's how you do it..it's possible.
Focus now on fixing the broken part which I understand to be the line? A prop valve is a chunk of steel, you didn't really break it.

Are you a Junior?! Oh no he's a junior!
You're gonna have to buy a bumper sticker too pal! :p

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Old Guy Bill

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I’ve bought a lot from Inline Tube, brake & fuel lines, & valves.
Check this site for the proper one.
 

fast 99

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What exactly do you mean by nut broke in the valve? Sounds like it could be removed somehow.

Ford had a non-resetting switch/valve back in the mid to late 60's. Was a pain to get the brake light off. As far as I know most later designs automatically reset. If the switch sticks to one side or the other, it is likely dirty inside. It's been so long, long time since I had to re-set one of those switches.

As far as a replacement, try a pick and pull yard. I've said it a few times here, GM used is better than Chinese junk. It is unlikely the exact same part number could be found in either case. 1 tons aren't exactly common.
 

Ajax19

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Bleed the opposite of the valve is blocking the rear flow bleed the front a few times and vise versa just went through this when I had a leaky rear wheel cylinder had to open the front bleeder and really stomp on it a few times heard it click and had flow again an was able to bleed normally might need to give it a few love taps with a mallet
 

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