AFAIK about all drum brake vehicles have self adjusting brakes since the early 60s, was a big deal back when... Still was common to see 99 cent brake adjust specials at Goodyear, Firestone etc service centers, till the early '70s... As already pointed out they are more for maintaining vs correcting a badly out of adjustment condition, also they only self adjust when backing up... A few quick stops in reverse may help...
I know disc brake cars don't have self adjusters on the front. I'm getting old and don't remember if front drum brakes had them.
Self-adjusting brake came out in 1963...disc brakes area different design and don't need self adjusting
i hope it doesnt take a minute to stop. are saying its doesnt have a lot of stopping power? or that the pedal has to travel a alot before it will start stopping? did you replace the brake shoes and or drums? were the shoes soaked with brake fluid from the leaking wheel cylinders?
"Self-adjusters", as stated here by others, make only fine adjustments, and work when applying the brakes in Reverse and then applying them going forward (so it's a 2-step process). Their purpose is to maintain adjustment, not to adjust brakes that were never adjusted to begin with. The brakes still need to be adjusted each time a brake-job is performed.