Proportion Valve was Leaking. Replacement won't center?

[Ratone71]

Here we go:

I installed a front disc brake conversion kit on my 70 C10 about 3 months ago. Everything was fine until a couple of days ago.

I noticed a soft brake pedal. I noticed the proportion valve was leaking from the nipple on the front. (discs front and drums rear). I ordered a replacement from POL. I put the new proportion valve on and now it keeps shutting the rear brakes off.

Here is what I have tried so far:

Recommended by POL:
1. Reset the valve by removing the plug for the light. Then bleed again. That didn't work.
2. Reset the valve. Then bleed to gravity. Then press it once to the floor when you bleed. Do not pump it a couple of times like normal. Once fluid starts flowing bleed it normally. DID NOT WORK.

My own research:
1. I used the document off the CPP site regarding brake issues. That did not work.
2. BLOW THE TRUCK UP!

Any other ideas?

[54Caddy]

Get that tool that CPP sells that will go in where the plug will go and wont allow the valve to move over so you can bleed brakes.

[502ms]

Don't blow it up! Ship it to me..
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[way2lo2]

Light pressure when bleeding will center the valve everytime. It drives the guys in the shop nuts when they can't get it centered after bleeding for 15 minutes and I'll jump in and get it after three pumps. Don't try to push the brake pedal through the firewall. Having the brake safety switch on the combination valve wired to a bulb helps by letting you know when its centered, at that point its even more critical that you use light foot pressure and don't push the pedal all the way down until you feel a bit of resistance.
The best way to have the valve not center is throw that combination valve in the garbage and get an adjustable proportioning valve.

[Ratone71]

I tried the soft foot without success. So, I ordered the tool to center the valve. We'll see how that goes.

Thanks Guys