[Tim Corcoran]

When I bleed the brakes fluid is coming out of all four locations so I know there is no blockage. I know based on the pedal going to the floor that there is very little pressure going to the brakes so I don't see any reason to check the pressure. Look at the photo on my original post you can answer your question about reservoir size it's one common reservoir for both front and rear systems. One shaft with two independent pistons both the same size. All rubber lines have been replaced with new parts. There is some slack in the brake pedal so the plunger is returning fully when letting the brake off.

[lust4speed]

I'm confused. Can you get pressure for the rear port when bench bleeding? If not, I've had good success like Schurkey said with the syringe back-bleeding the MC. If you can't get pressure on the bench, then it sure points to being a master cylinder problem.

If the MC bleeds okay and you have problems on the car, then you might have the same problem I did with my drag car. Same scenario of multiple master cylinders and quarts of fluid to the point where I was thinking about replacing everything. The problem ended up that the caliper brackets on the rear axle were ever so slightly tilted where the bleed port wasn't really at TDC. That kept a little air bubble on both sides that was enough to absorb braking force. Ended up removing the bottom caliper bolt and rotating the caliper slightly and that released the air bubble. Whoever shortened the rearend got the geometry a little off when welding the ends on. They were only off a few degrees but was enough to leave an air bubble.

[Schurkey]

Originally Posted by Tim Corcoran

Look at the photo on my original post you can answer your question about reservoir size it's one common reservoir for both front and rear systems.

I haven't needed to dick with Chrysler master cylinders in decades. MAYBE what you say is true.

I'd be enormously surprised if there isn't a molded-plastic divider in that "reservoir", making two independent or semi-independent pools of fluid. Where that divider is placed could make for a large front reservoir, equal reservoirs, or a large rear reservoir.

If there's no divider, why are there TWO fill-caps? YOU ARE POURING FLUID INTO BOTH FILL-CAP OPENINGS...RIGHT?

The whole point of having two independent hydraulic systems--so if one fails, the other is still able to stop the vehicle--would be undermined by having both hydraulic circuits feeding from a single fluid reservoir. If there were a fluid leak in one circuit, it'd empty the reservoir for both circuits, potentially leading to total brake failure.

[389]

Jack the rear end up to level the master cyl out..

[Tim Corcoran]

Originally Posted by lust4speed

I'm confused. Can you get pressure for the rear port when bench bleeding? If not, I've had good success like Schurkey said with the syringe back-bleeding the MC. If you can't get pressure on the bench, then it sure points to being a master cylinder problem.

If the MC bleeds okay and you have problems on the car, then you might have the same problem I did with my drag car. Same scenario of multiple master cylinders and quarts of fluid to the point where I was thinking about replacing everything. The problem ended up that the caliper brackets on the rear axle were ever so slightly tilted where the bleed port wasn't really at TDC. That kept a little air bubble on both sides that was enough to absorb braking force. Ended up removing the bottom caliper bolt and rotating the caliper slightly and that released the air bubble. Whoever shortened the rearend got the geometry a little off when welding the ends on. They were only off a few degrees but was enough to leave an air bubble.

Mick
Yes that is the problem I can't get pressure on the rear port of the MC my rear brakes are drums front disc. I have the tool that Schurkey noted and used it too.