On/Off Water Valve on Washing Machine Possibly the Problem

[conishkee]

I'm painting the scenario and asking for assistance wherever I can get it, 'cause I'm at a loss. I have a 12 yr. old Whirlpool Stylemaster # 4213632 Rev. B washing machine. It recently started acting up when I set the dials to fill water in the tub. I was in the kitchen and heard something strange. When I ran to the washroom, the water had overflowed out the tub and was going everywhere on the floor! I had to immediately turn off the water. I haven't gotten it fixed yet, but when I do laundry, I have to babysit it by listening to the clicks and turning the water on and off manually. What on earth could the problem be? Could it be an on/off valve in the washing machine itself? Is it fixable, or should I give up and save up to purchase a new machine? HELP!!