1940 brake issue....

[adavis]

I pulled the front drums off last night. The shoes are basically new as well as the wheel cylinders but the drums have some grooves. The shoes dont appear to have been "arched" to match the drums as there only looks to be contact at either end of each shoe.
I have a pair of nice late style heavy drums that look excellent. I dropped them off at the local shop this morning to be cleaned and trued. I had to order new seals so I'll get them installed next week. I'm also going to sand the shoes to match the drums once I get them back.
When I adjusted the brakes I first loosened the outer nuts on the lower adjusters then spun the wheel and turned one adjuster till it drug, then backed off till it was just free. I did the same to the other lower adjuster and then tightened both nuts. The I moved to the two upper adjusters (eccentrics?). I spun the wheel and turned each adjuster until it drug then backed off slightly. If this is not the correct procedure feel free to let me know.
I'm using plain old DOT3 brake fluid. I have new speed bleeders installed on all corners and have ran fluid through each wheel until there are no bubbles....and then ran more fluid just to be sure.
Thanks again for all the input. I still can't believe that brake adjustment would be the culprit to my brake pumping dilemma, but I'm going through everything and learning while I do it. I'll keep you posted on the outcome.....

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[George/Maine]

If you have new shoes there are some shoes that are made wrong.
The bottom hole is off location.
If you put shoes in drum make sure the lining hits all drum, chamfer ends.
Now look and see if any of the shoe is less then 1/4.
What I mean is if you wore down the lining the bottom 2" should not hit drum.
If you have old shoe look at new shoes at bottom hole.

[adavis]

So I have an update. I swapped the front drums with a pair of freshly turned drums that measure 12.050". I pulled the master cylinder and bench bled it. After I reinstalled the MC I bled the system starting with the right rear wheel. Using speed bleeders I'm able to do everything by myself with the car on my lift. I can pump the brake pedal by pulling down on the arm from under the car....giving me the ability to watch the clear line I attach to the bleeder. It took about 25 slow pumps to get completely bubble-free fluid out of the right wheel cylinder. Moving to the left rear cylinder it only took about 10 pumps. Right front was about 10 and left front was about 3.

After all was done I can say that the brakes are as good as I would ever expect original 1940 drums brakes to be. The pedal is firm each press and feels very solid. I have found an old Ammco brake shoe arc-ing machine and will be picking it up in a week or so. When I get that machine I'll double check the shoes just to make sure, but right now I'd consider the brakes good.

Thanks everyone for the information and advice. I'd say that the problem was a culmination of several things....from brake adjustment to bench bleeding the master cylinder to starting at the right rear wheel when bleeding the system.

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[Mart]

Cool. Thanks for the update.

Mart.