Once you have the adjuster threads freed up, do the adjustment the right way. With the tire and wheel bolted on, tighten the brakes until there is a firm drag when the wheel is turned in a forward direction. Don't adjust it tight enough to lock the wheel completely. Then back off the adjuster screw one turn- - - -that's usually 10 notches on the adjuster wheel, but count the teeth to be sure. Adjusting screws for self-adjusting brakes have fine teeth, usually 20 instead of 10. Don't worry about drag- - - -once the adjustment is loosened it's possible for the shoe assembly to shift and drag a little even when it's adjusted properly. The brakes will self center the first time they're applied. Adjust the other three wheels the same way and drive on!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!