[NVMiner]

When starting cycle the machine overfills the tub could it be the timer or the water level switch?

[applianceman]

I don’t think it is the timer although the water level switch could be the problem. Here is what I suggest. If turning the washer stops the water flow check the tube that runs from the water level switch to the tub. It may be clogged up, broken or just off, make necessary repairs. If there is nothing wrong with the hose replace the water level switch.

If when you turn the washer off the water keeps running forcing you to turn the water off at the wall the water valve is bad.
Clothes Washer Repair Guide