The brakes were changed to discs in the front by the previous owner, and the work they did with the proportioning valve makes me wonder a bit? The car feels like it brakes a lot with the front wheels, easily locks them up. There are two blocks underneath the master cylinder, I thought that usually you only had one? Does this setup make sense? The lines look hokey as they are, maybe I should rebuild this area.
I am sitting here trying to make sense out of it lol. Looks to me like the brake line coming out of the front is pinched shut. The block under the prop valve has two brake lines coming out of it, one for each caliper correct? Where is the brake line coming from off of the prop valve to go to the rear end?
Does anybody else find it kinda' strange that the brake lines exit on the engine side of the master cylinder? And that the proportioning valve isn't attatched to the frame?
Kimson, this is just odd and really should be fixed. I'm afraid I can't ID the make of the components, but it should be looked at soon. If you have a savvy shop around, they may be able to set things straight There's too much cobbling going on there. The fact that one outlet on the valve is plugged via pinching the brake line, plus no support for the valve itself is really bad news. If you want to try to do it yourself, get rid of the two valves and install an aftermarket adjustable proportioning valve so you can adjust the brake bias right. Warning, all brake line flares must be double flares, and that's not exactly a job for the faint of heart. The inexpensive flaring tools available make the job quite difficult, and they really need to be right. Devon
yea, I think you need to start all over in that area. Get a correct type master cylinder and proportioning valve and rework all of your brake tubing. Looks like a mess.
The earlier disk setups did not use a proportioning valve. For example, the 1970 GS had a valve mounted on the brake booster. It is a hold off valve installed in the front brake line. It's purpose is to delay application of the front brakes slightly. By having the rear brakes apply first, it keeps the car more stable. There is often a check valve in the rear brake line. It's purpose is to keep a little pressure in the lines to overcome the pressure from the brake return springs. Later systems, 71-up, used a combination valve with a built-in proportioning valve. The proportioning valve works differently. It's purpose is to limit pressure/flow to the rear brakes under hard braking conditions. That will prevent rear wheel lockup. Some aftermarket ones are adjustable. It looks like your system has the early hold-off valve, and a distribution block. A common replacement is the brass combination valve. Includes all the valving you need, costs about $80. Aftermarket brake line companies like 'The Right Stuff' might have conversion kits with master cylinder, combo valve and lines. That would be your safest bet.
