there should be a section in the chiltons manual. there's a small elongated hole in the bottom of the backing plate. the hole is on the side facing the rear end. if you have a brake adjusting tool you can put it in there and turn the adjuster. can't remember which way it turns to loose it. if you have problems with it, you might take off the wheel and drum and you can see the adjuster. bottom, middle, thing with teeth on it. you can turn it there to tighten or loosen the brakes. hope this helps a little.
I thought that only worked to tighten the brakes, not loosen them. I think you have to spin the adjuster wheel to by hand to loosen them. If you find it difficult, you can pull the drum off and do it from the inside. (oops, don already covered that )
Unless you have done this before you will not be able to loosen the back brakes unles you take off the back drums. Then you can loosen them. My guess is the reason they are locking up is because they are too tight.
I would bleed all 4 brakes,,,,back may only be working now. How are the front brakes? Who put the new shoes on?
I did this too, I had put a spring on incorrectly and when I lightly touched the brakes, one wheel (the one I just rebuilt) would immediately lock up. Verify all your springs are on correctly.
You can loosen the brake adjustment through the little hole in the backing plate. You need to use a screwdriver or something similar to push on the latch plate while you move the star wheel downward. To adjust the brakes, jack up the car. Tighten the brakes by turning the star wheel upward until you can't turn the wheel by hand, that seats both shoes evenly. Then push on the latch plate and turn the star wheel downward until the brakes just barely rub.
