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PackardV8,

Yes, the master cylinder is a tandem style. And that is also a yes to "drums" all around.

I was outside making better seals around the bleeder screws, and got better results this time. A fair amount of fluid was flowing through the lines. That should help to bleed it the standard way, with the bottle and clear line. There was definitely air escaping through the threads. So now she should be able to pull fluid up once I let off the pedal.

Do I have the lines for rear and front connected properly? The larger outlet on the master cylinder goes to the front correct? Since PackardV8 brought it up, I just want to make sure.

Do I have the lines for rear and front connected properly? The larger outlet on the master cylinder goes to the front correct? Since PackardV8 brought it up, I just want to make sure

Keith, I Was curious about that too. My ports are unlabeled and all the same size as is reservoir(s) and piston diameter. I guess logically the rear or primary piston should go to the front since front does most of the work but with the typical two piston construction and all else identical in size, does it matter?

I see on the MPB site, they have a chart showing cylinders which appear almost identical yet are different front to rear. Some have a larger reservoir, others maybe a residual valve may be inserted on one port but if everything else looked similar how would you tell.

The way I connected it was front to front, and rear to rear. The bore appears to be the same, yet the outlet closest to the front, where the line connects, is larger in diameter. A larger diameter would indicate to me that it should go to the front. Correct?

And as far as the push rod length is concerned, the booster came with it pre-installed. I read that if it is pre-installed, it has alrady been properly adjusted.

As far as bleeding technique is concerned, I think Ross has it right. That always worked for me. Keep it simple. I have never had much luck with the vacuum bleeders.

Just found the installation instructions, and it says, "Attach the brake lines as indicated above". The only catch is, it doesn't indicate above. Guess it doesn't matter if they don't list it. Either way, I am going to try it out this way and determine whether or not it the location of the lines matters. The bore is 1" inch on both.

Craig,
How do you have yours setup? Rear lines to front outlet on master cylinder, or the other way around?

-Garrett

Is yours one of these? This pict from MPB shows their common cylinder plumbing. As mentioned above, mine is not labeled and not MPB but am going to reverse and see if there is a difference.

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Howard, you are the man!

MC1001PZ, that is the master cylinder I have exactly. Did you find that on their website? I tried looking around and couldn't find it. Darn, that means I have to switch the lines! At least I haven't gotten the system bled properly yet.

Thanks-a-million Howard

-Garrett

I can't say that i've wroked on every tandem cylinder equiped vehicle ever made. So there mite always be exceptions. BUT USUALLY the port nearest FRONT of cylinder is for the REAR brakes.

Also there is at least two different internal piston designs.

Regardless, back off the shoe adjustment on all 4 brake shoes so that the shoes are very loose out of adjustemnt. Remove the line from the mc that feeds the FRONT brakes. Install a hose or tube into the same port and place the other end of hose into RESERVOIR of MASTER CYLINDER. Make sure the mc reservoirs stay full of fluid. MAKE SURE the end of the hose placed in the mc reservoir is always below the fluid level. We should be dealing with the MC port closest to front of car and furthest away from brake pedal rod in this case.

Now bleed the REAR brakes.

Reconnect the mastercylinder brake line.

Repeat above process for the bake line that feeds the FRONT brakes.

Adjust all 4 brake shoes as per manual.

Vacuum bleeders are makeshift at best. Bleed brakes with a helper. When bleeding brakes using a helper NEVER UNDER ANY CONDITION release the brake pedal while the bleeder screw is open. THE BLEEDER SCREW MUST BE CLOSED IF THE BRAKE PEDAL IS RELEASED even a tiny amount.

THere is a reason for the above process.

IF (NOTE I SAID "IF") the INTERNAL front piston that feeds the REAR brakes is SPRING LOADED against the rear piston that feeds the FRONT brakes then the above process applies UNLESS a proprtioning valve is used. Even if a prop valve is used then above process should still work.