That style of machine
Ran for about 8-10 years, from the mid 80's until the early 90's and then the same mechanical design got a new more modern control panel.
If they are the same as the ones we had over here, Its probably one of the last TL washers with an Active self cleaning lint filter.
It has a recirc port on the pump, which pumps water into the tub ring and back into the tub. When it spin drains, all the lint is forced out of the tub ring and down the drain. The ones I've pulled apart always seem to have a clean mesh screen, so it seems to be effective.
I would say these are future keepers. Are they Porcelin enamel? The ones we got in AU were powdercoat, and it tended to just wash off over time.