1st gen chevy - need front brake proportioning valve asap

Can anyone tell me where I can get a new on of these? I need one asap.

,,,,,no such thing as a 1st or 2nd Gen proportioning valve,,,,,,now if you want to cut down on the pressure to reduce the rear brakes from grabbing if you were to add disk brakes up front,,,,,the Hot Rod shops like Jeggs and Summit have an adjustable one with a knob that you connect into the rear brake line  and dial it in so the van stops right,,,,,,you could also get a 3rd Gen Combination Valve which has the valves built into it actually made for Drum/Disk set ups,,,,,

Maybe a PO changed your brakes to a dual master cylinder, but they 1st gen's originally only had a single master with no valve....

No such thing? Ouch.
I have four drums and single master. My front passenger side brakes were not grabbing at all. I've go ahead and replaced all pads, cylinders, and hardware from kits on all wheels. The lines have been bled. The front pass side brake is still not grabbing. The guy helping me says buy a new valve, but we didn't look for one in use on the van.

What could be causing the problem? Clogged line?

,,If it has 4 drums, there aint no valve,,,,,,,,if you jack the wheel up, spin it, and it dont stop,,,,,either air in the line, wheel cylinder frozen,,,,,,clogged brake line or way out of adjustment,,,,,,do you actually get brake fluid out of the wheel cylinder when you bleed it,,,,,,a bad hose will close up when you hit the brakes and not let pressure get to the wheel cylinder,,,,,,,with the drum off,,,,does the pushrods push the brake shoes out when you step on the brakes?

If the wheel stops when you jack it up and step on the brakes,,,,,check and see if the shoes are on backwards or 2 primary shoes are on 1 side and 2 secondary are on the other,,,,,,and you do have 2 1/2" wide shoes on the front???? sometimes the LF is the problem and does not let the RF do its job......

Thanks Don, I'll look into these and see what we find.

Don could give a professional or collegiate level class in early G-series chevy van systems. His example photos and carefully cleaned and painted parts reminds me of the cutouts and displays of parts they had in aircraft systems class when I went through flight school.

No kidding, we're lucky to have him!

...I got a camera,,,,I got parts laying around,,,and people keep asking questions,,,,,it all fits together,,,,,and it gets us on the same page,,,,,,,(proportioning valve is in a different book)

That's why we call Him the  G O V E R N O R .................. or gov for short !!!!!!!

Don Please ... Eat Your salad .... Cut back on the Smoking  and just take care of your self in General .... also  How's that cholesterol ???????? Lol ............ We got fords to Build !!!!!! and a Chevy or Two !!!!

I would also make sure that one of the rubber hoses isn't collapsed. I didn't see if you changed them or not, but they can become clogged, or break down from the inside, and look normal on the outside.

Hey Guys,
We did replace the front hoses and dialed out the adjuster and things are fine now. Thanks for all of your valuable input. The next project will be exhanging the single master cylinder for a DMC.

I`m from the show me state, and pics are worth a thousand words!!!!!!!!!!!!
Don does an excellent job with the pics!!!

,,,I put up pictures so I don't have to type,,,,,,these hands are made for wrenches, not hunting for each letter on the keyboard,,,,my finger is starting to hurt already.......

and these pictures are because someone asked a question about something,,,,,and I took a picture for them to make sure we are on the same page,,,,,,so you guys are really the reason I got like 10,000 pictures of stuff,,,,,,,they are your pictures,,,,,,,

Like panelman said Don, pictures, especially your pictures, are worth a thousand words. They help clarify any discrepancies that might exist because we have different names or interpretations of names for the different parts of these vans. Your pics help us to understand what you are telling us and that is "Priceless" to all of us, especially to those of us non-mechanic types who would like to do some things that we feel aren't too complex in order to save some bucks for the other things we don't feel comfortable with attempting and have to pay someone else to do.
There are a quite a few people on this site with strengths in different areas and who are willing to share their knowledge and tips and that's what this site is all about. Vanners are Good down to earth people!!! Thanks for all you do Gov'na!

I don't quote the Shop Manuals,,,,,I had to read them all my life,,,,,,my explanations are as if you are right there looking at it while you are working on it,,,,,,,and using simple words,,,,,