I saw a thread on Honda-Tech where a poster showed a rubber plug that he pulled out of a Proportioning Valve. Here's a picture of the one in my car after I cleaned it up a bit. I think I'll just replace it with a new one ... about $150.

 

rubber, metal.....just under that amount of pressure, I thought it would be hard to have rubber hold.....now there could be a piece of rubber over the metal ball to protect it from rusting.......anyway, let us know how it goes.

 

the prop valve O ring CAN'T be replaced. Honda nor anyone else I know sells this part. You have to buy a new prop valve. Also the rear disc and drum brakes prop valve are different. But not by much. I'm using my drums prop valve on my rear disc swap. I THINK the cb7's rear disc are ABS. So you will need the ABS prop valve. Or you can use a DA intergra 40/40 prop valve (non ABS) if you have done the ABS delete (like 99% of cb7 guys do)

 

Thanks ... the Accord is the Value Package model with the drum rears and no ABS. I'll make sure I get the right part.

 

There's a rubber seal thing between/inside the 2 sides of the proportioning valve with a spring and someother stuff IIRC the memory is a little fuzzy on that. I went to the junk yard to get a replacement (remove your own) I removed the master cylinder to get to it and informed the yard guy I was going to just cut the lines. My proportioning valve is bolted together with the mounting bracket in the middle. The bolts are security bolts that will cross thread when removed (if you want to open it up to clean and check the seals) I removed the bolts by using a mini grinder w/ cut off wheel and chased the threads with a tap then grinded down the rounded shoulder flat so I could put a nut on the new stainless steel bolt also the mounting bracket was rusted so I wanted to use my old one.
Save yourself the grief of taking it appart, find one still on the car w/ low mileage with fluid still in it and not weeping from the whole. I paid $20 and I got a rear defroster switch for $5 since the light burnt out on the old one. he wanted $20 for every small part but I said I'd give him 5. If you get one from those places where its already parted out, you won't know if its already weeping.
YMMV good hunting
If you go to the junk yard and remove your own make sure you bring a long magnetic extention or grabber to retrive any stuff you drop. Its not like home, some cars have no tires and stuck in mud.

 

I just ordered a new valve online ... about $140. Figured I'd have to remove the MC to get access to the valve; been meaning to replace the MC for years ... I have an excuse now. I just can't go cutting the lines . Thanks for sharing your insight.

 

Changing out the proportioning valve ... what a pain! I just got the valve out and it took me hours to do even with the master cylinder out of the way. Taking a short break before I dive back in to install the new one. The little rubber stopper in the middle is missing and I believe there's where it was leaking fluid.

 

What made removal so difficult?

 

There just isn't that much space to swing a wrench to remove those hard-line fittings. Found out you can reach the lower front fittings from below the car too. The mounting bracket bolts were difficult to reach. After starting the one mounting bolt that you can see from above, I used a 10mm magnetic nutsetter to start the other bolt that was obscured by the bracket. The installation wasn't too bad. It was just difficult leaning into the engine bay for long periods of time cranking on those brake line fittings. But after doing it once, I think another time wouldn't be quite as bad. Assembly went much smoother. Bleeding the brakes now.

 

Got the new proportioning valve installed. Here's the new and old valve side-by-side. Notice the missing plug on the old one. Installed a new Master Cylinder too. Gave me a good excuse to flush the brake lines with new fluid, which was 6 years old and pretty nasty looking.