I've got a leaky Proportioning Valve, the one with the big hex-nut under the master cylinder. I'm 99.99% sure it's leaking from the back of the valve,..past the little rubber boot.

The PV is original to the car, a 69. Two questions:

1) Is there a kit or anything I can do to stop the drip?

2) If not, is there company who can rebuild my original?

I purchased a repo once and I could never get the brake line connections to stop dripping,..so I'm not interested in this solution,..plus I want to keep the original PV if I can.

Thanks in advance!

A poster on the CRG forum a couple of weeks ago had his rebuilt for $65.00 by Karp's Brake in southern California, (909) 985-0800. :thumbsup:

John Z,..appreciate the info,..I'm on the phone now.

Update,..Ron at Karp's can rebuild the PV,..about a one week turnaround,..$85 (sounds like he's a had a rate increase,..still a good deal though).

Thanks again John Z.

heartbeat city has rebuild kits for about $40.

I just rebuilt one.
Got the kit from Heartbeat city auction. You get 3 rubber seals. Sombody is making some money. The end cap is generic. Just a plain cap. My PV had an additional rubber seal within. I just reused it. I did take a cylinder hone and lightly cleaned the inner cylinder. I took Pictures if you want to see what's inside.

Kurt :beers:

The seal that leaks is just an O ring. You can get one at a local hydraulic store for pennies, just get one that is brake fluid resistant, such as:

"Ethylene Propylene (EPM, EPDM, EP, EPR)

This compound found broad acceptance in applications requiring excellent resistance to Skydrol and other phosphate ester fluids at higher temperatures. In addition, o-rings in these compounds exhibit excellent resistance to automotive brake fluids and steam. Ethylene Propylene compounds are also recommended in applications requiring resistance in hot water/steam, weather, ozone, abrasion, tear and tensile strength. EPDM has a temperature range of -65°F to +300°F."

The stem seal I removed from mine turned out to be a cup seal like in a master cyl. I cant see myself paying $40 for a few seals, even if they are hard to find. Maybe I'll try an o-ring when i get around to rebuilding it.

I only remember 3 seals. An oring under the cap nut, a flat rubber on the plate, and the cup seal. I would be interested in your pictures camsdad.

here's one of my pics:
http://img102.imageshack.us/img102/6797/meter120qx.th.jpg (http://img102.imageshack.us/img102/6797/meter120qx.jpg)

I went back and looked at a photo that was sent to me and I can't tell for sure what seal is on the plunger. If it's not an O ring, you could probably substitute a "Quad ring" or O ring. This metering valve really isn't needed if you dont drive on snow/ice...

"Quad ring" eh? I had never heard of them until now. Cool. I've heard of people putting square cut rings in there that worked too.

I'd like to have one just because it looks factory, and my car's not afraid of snow again-yet ;)
The valve is also good for people like me who do long slow light stops, or might get stuck in traffic, so they get more use out of the back brakes (or for people who do 2-footed driving with an automatic trans). I found some specs on some factory valves that have a higher psi spec for police and taxi (as high as 160psi). And reports of an old Lincoln bulletin for premature front wear for some (older) drivers, with a higher psi spec'd metering valve as the cure.

Finally got my pictures up.
Here is what mine looked like.
http://home.pacbell.net/camsdad/Brakes/DSC03368.JPG
Internal Parts
http://home.pacbell.net/camsdad/Brakes/DSC03371.JPG
Large hex nut and seals.

http://home.pacbell.net/camsdad/Brakes/DSC03375.JPG
Parts cleaned up.

Excellent pictures!
I forgot about the stem boot. Mine was gone.
Is it the flat rubber washer (3rd piece from left) that wont come with the heartbeat kit? I might have to get it, if only for the darn dust-boot :(

You could probably make the one on the left if you get some sheet EDPM and punch a hole in it, then trim the outside.

A quad ring looks like two O rings melted together, the side has two rounded ridges with a slight groove in the center of the edge. It would fit in a space for a square edged O ring.

Ok,..I've rebuilt the propertioning valve,..very easy. Thanks!

Question,..is it now necessary to bleed all four wheels?...or just the fronts?

It wont hurt to bleed all 4.
If no air was introduced to the rear circuit while working on the front circuit, there shouldn't be any air in it to bleed out, just old fluid.

Yeah I did all four,..but don't think I needed to.

How does the one switch (for the dummy light) monitor both rear and fronts,..yet keep the fluid for each separate in the distr. block?

Curious...

There's no fluid in the center, sealed off by the orings.
The switch connector pin goes down into a v-groove on a shuttle valve in between front and rear circuits, and is screwed to the valve body by plastic, so is basically free floating, not gounded.

The shuttle valve remains centered by springs and pistons, and by equal fluid pressure on both sides of it. When fluid pressure is unequal, and is enough to overcome the spring pressure, the shuttle valve shifts towards the failed circuit, causing the v-groove to no longer be centered around the switch pin.

The switch pin is then touching/grounded to the shuttle valve, which is in turn grounded to the valve body by way of its springs/pistons, grounded to the chassis by being bolted to it. Once the pin is grounded, the circuit is complete, and the light comes on.

at least, that's near as i can figure it ;)