My brake proportioning valve...

is probably allowing brake fluid to bypass cuz over time my front master cylinder reservoir depletes into the rear reservoir. I'll take the cover off and all the rear reservoir oil spills over... ugh! I changed out the master cylinder at least 3 times and it still happens. The reason I believe its my proportioning valve is cuz I applied heat to it when I reconditioned my jeep. I think I needed to braze it for some reason, forget just why. But I guess my question is this: Did the 76' jeeps have front disk brakes cuz I found a proportioning valve for a 76' but could never find one for a 74. I'm just hoping that one of those will work. Thanks for reading
CrossHair

 

76 CJs have front disk brakes.

 

actually 1977 was the first year for disc on CJ models
1976 would still be drum
1977 and mid 78 would have the 1-3/16" "thick" rotors;
these can be identified by a caliper anchor plate held with 6 bolts to the knuckle.
mid 78 and later would have the 7/8" "thin" rotors;
these can be identified by a caliper anchor plate held with 2 bolts to the knuckle
can get confusing at times

 

Well then WOAH!! if thats right I will be able to use that 76' proportioning valve, I'm going to go for it. Thankyou!!
CH

 

1976 CJ-5's were available with front disc brakes.

 

IIRC that's correct - optional front disks, but all that came through and that I saw had them. No documentation though.

 

you know why i'm asking is cuz I hear if they have front disk brakes then the amount of brake pressure will be different for my drum brakes... is this correct?
CH

 

There was not a prop valve in the 4 wheel drum systems it is not needed because all the wheels were to get the same pressure. The disk systems needed the prop valve to allow more stopping power to the front to be more efficient since they will not lock up as soon as the drums will

 

I just finished converting a '73 D30 to disc brakes. I used a 2lb residual valve for the discs and a 10lb residual valve for the drums and an adjustable proportioning valve for the rear (drums). So far I haven't had to adjust the proportioning valve at all. It's running wide open. Could be that the shoes are shot and that's doing the proportioning for me. LOL Discs were introduced mid '76. Just to screw with the parts counter guys. The discs are 1 1/8" thick, not 1 3/16" as mentioned above. Summit Racing has Wilwood PV's. A lot cheaper than the stock Jeep valve.

 

So now you think my 74' doesn't even need one? It has all drum brakes. I recently installed a brand new master cylinder (last week); I'll betcha when I take the cover off the front reservoir will be empty and the rear reservoir will be full. I know its that prop valve... if I don't need it then I'll just get rid of it all together. But only if you're sure LOL.
CH

 

There is definitely no need for a proportioning valve with 4 wheel drums. They are only used with front disc/rear drum combinations. Good Luck.

 

Yea today I took a look at that proportioning valve that I had and pretty much did away with the shaft that was inside of it. I think the chambers will pretty much be seperate now. Now I'll drive it for a short while and see if my reservoirs stay full. Thanks for the info on whether or not I actually needed a proportioning valve. I saw elsewhere on the web that its unnecessary to have one for a four drum braking system. Talk to ya later,
CH