My brake system consists of the following:
1. Front '79 Waggy D44 calipers
2. Rear '85 Cadillac Eldo calipers
3. '78 Cadillac Eldo M/C
4. '85 GM Dual-Di booster
5. Stock CJ prop/combo valve

My pedal is very mushy and will go all the way to the floor. I have bled the system several times, but I will try again if necessary. I would like to modify the prop/combo valve for the discs. Can I remove the o-ring or plunger from the rear section of the valve? Here is a pic:

http://home.off-road.com/~tom85cj7/prop.jpg

Which items need to be removed?

Thanks,
Tom

Good question. I need to watch this thread.
I was told the residual pressure seal in the MC had to go. However that's for a MC that was orignally for drums.

Nothing was said about the proportioning valve. I have mushy brakes, too.

Use the search function there is a long thread on this that tells you exactly what to do. Yes remove the O ring and it increases flow to the rear disks. It's setup to limit flow b/c wheel cylinders require less fluid that callipers but since you're running calipers on the rear you want to have more flow to them to lockem up.

I did search..............

None of the posts apply directly to the CJ valve. Do you have a CJ? Have you done this before? Give me a real answer if you know what you are talking about. Are the CJ and YJ valves the same? What about the plunger?

I'm running four wheel disks and I haven't removed anything from the valve. I put a proportioning valve inline between the MC and the pfitzer valve, and my rear brakes work fine- firm pedal.

I found this:
http://www.pirate4x4.com/forum/showthread.php?s=&postid=612446#post612446

Now a bit of advice. Don't go yapping your mouth. You'd get flamed faster than shit by people you want to help you.

Know what I mean? There's a bit of time before you can flame back.

No need to flip skip! Just trying to help ya out. You're gonna blow an O ring if ya trip that easy.........:flipoff2:
http://www.pirate4x4.com/forum/showthread.php?s=&threadid=688&highlight=proportioning+valve

Sorry for the blow-up:mad3: ...

Okay those posts are great, but I have read them before. The CJ valve isn't like the YJ valve. It doesn't have the vent on the front or the metal plunger. I will probably remove the o-ring in the picture and see what that does. If I have to I will drill out the entire rear section and disable everything. I just wanted to see if anyone had modified a CJ valve or not.

Thanks,

this same thing kicked my ass with my 1-ton stuff. bled bled bled and bled, removed prop. valve alltogether. still no pedal. I have the Navaho stuff 1-1/4 MC dual booster. turns out the rod between the booster and the MC had too much play. there isn't much movement there and a 1/32 can mean alot. I found a chevy tech artical that said 1/64 gap between the two....PLOW, brakes. GOOOOOOD brakes. All I can assume is Harold Off put the system together for stock cj's. and all that pedal wasn't necessary??? Anyway, try that and see what you got. BTW I got a brand new corvette MC collecting dust cause of that fiasco...

I had the same problem with the mushy brakes, had nothing to do with the prop valve, I went to a mc from a 70 trans am and that fixed my prob, all the pedal in the world now, I run 11 inch waggy brakes all around with manual mc and the stock prop valve, although I do have to do something with the prop valve because of the resid pressure ment for the drums , the rear brakes get warm on the street...

is this the same for a YJ system?