I was going to rebuild my valve. Took it apart and wondered if
anyone just gutted it out and run it like that to help the bleeding process?

 

You can try it but I think you will have to much rear brake. I had an old van with to much rear bias and it was more or less unsafe to drive. It will fell fine until you really need them. Them your screwed...

 

Why not buy an adjustable valve from Summit Racing. Then you can adjust the balance to the way you want it.
Duane

 

FWIW: it isn't a proportioning valve; it's a pressure differential switch. GM thought it necessary enough to install one on every C3. In working condition, it doesn't have much affect on bleeding.

 

My '68 diverter valve was clogged internally preventing the diverter piston from centering itself and allowing me to bleed the brake system...when working correctly, it prevents total brake failure by allowing either the front or rear brakes to remain operational....




The warning switch must be removed first to allow the internal parts to be removed.....it was also clogged/frozen and had to be disassembled/cleaned........




The internal parts were unrecognizable until I cleaned them....




You MUST bench-bleed the assembly and cap the ends of the lines to prevent fluid loss before re-installing it on the car (OR.....you can waste a day like I did otherwise)


I have great brakes now........

 

It was just a thought. I have mine apart now and waiting on rebuild kit.

 

Members have deleted their internal parts with no problems.

I'm just trying to avoid "what's his name"............

Murphy's law -
Murphy's law is an adage or epigram that is typically stated as: Anything that can go wrong will go wrong.

 

Seems the brakes will work perfectly without this valve until the day you have a leak in either circuit and the pedal will go to the floor whereas with the valve you will still have enough brakes in one circuit to pull up the car. That's my understanding of its purpose, I would feel more comfortable with it in and working but what are the odds of a brake leak......

 

EXACTLY!!
I never could understand why people want to remove/gut these!! Just fix it or replace it!

 

So Mike when I'm gravity bleeding my brakes I don't need to worry about the pressure diff. switch being centered? I thought I read somewhere that I would need to bleed one rear and one front at the same time so it would center it self so you get fluid front and rear.
Thanks
I hope I did not step on this post.

 

C3, not the case. Just follow the proper sequence in the shop manual and you will be fine if your system is in good order. I believe it is:

Left rear inner
Left rear outer
Right rear inner
Right rear outer
Left front
Right front

 

Since the front and rear systems are independent, it is not necessary to bleed the rear and then the front. You can bleed the fronts and then the rears with equally good results.

Also, the switch has two functions.
1.) If you loose pressure in the front or rear, the pressure differential will force the floating piston to one side and cause the BRAKE lamp on the tach to light up.
2.) in the event the condition in 1 occurs, the floating piston will prevent total loss of brake fluid in the side with the leak.

If yor want to eliminate the switch, don't gut it. Plumb past it, keeping the integerty of the isolated front and rear systems intact.


Pete

 

When bleeding the brakes, you DO need to push pedal down rather slowly, so that the shuttle valve won't shift to one side. Other than that, you don't need to do anything special.

 

Got my rebuild kit





cleaned up with new orings





new seats





lots of q=tips

 

You are probably right about this brake valve; however, GM calls it a brake fluid distribution/proportioning valve.

 

It is one of those insidious failure points on my brakes that I will never forget, brakes would be functioning one day/week, and then the light would come on and the pedal would be even softer than 'normal' which to ME is anything BUT.....so back to bleeding brakes and finding air in the lines yet again, finally wondering about it on the frame down forward a bit, I pulled it apart TWICE, and found out something hard to believe, that in fact the switch itself will act like a one way valve that will let air into the system and weep fluid just the smallest amount under pressure, or for that matter just setting, drove me krazy, finally thought to just replace it with running rear lines to the m/cyl directly and then the same splitter block in the front, that the rear has....that stupid recurring air in lines problem went away and brakes were consistent as could be for a couple years......

but years later I got convinced to try a Hydro Boost system for the booster because the pedal never was much, always too much travel, and too spongy at the bottom, even though car stopped ok, never liked the feel.....much worse than the typical GM brake pedal feel.....adding the HB cut pedal travel by 1/2 and much more solid feel at end of travel, not some spongy crap.....sharky stood on the nose and put my nose into the wheel......

 

Yes,Hydroboosted mine as well. Good set up.

 

Who sells the rebuild kits?

 

https://www.musclecarresearch.com/gm-3956727-autopsy

It's a great site with some cool stuff. Paid under 13 bucks

 

It's going to be like brand new!






My center piece is different/ancient......................