I have a washing machine that occasionally will not stop filling with water in the initial fill cycle or the rinse cycle and overflows. Anyone know what might be the problem and how hard it would be to fix it? I bought a new one and tried to find a repair company that would take the old one off my hands with the thought they could fix it and sell it, but no luck there. So I thought I might try to fix it myself and sell it before I put it in a landfill. Also would give it away if someone wanted it to do the same (in Colorado).

There is usually a pressure switch connected to the tub by a rubber tube, this could be blocked or it could need a new switch.

That tube could also be cracked and can't hold enough presssure to trip the switch. Try pulling it off at the tub end and blow air by mouth to see if you can trip the switch.