Please note that you are in the wrong section, this is the dishwasher forum.

Here are your parts
Replacement parts for MAYTAG MAH5500BWW Washer - Horizontal Axis | AppliancePartsPros.com

Here is a manual
http://www.servicematters.com/maytag_library/docs/16010061.pdf
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my Maytag Neptune front loader washer fills with water when turned off. when I left town for a few days I turned off the faucets to the machine and when I returned it was filled with water. That sound impossible so I will accept that I had not turned off the faucets completely.[/COLOR]
Recheck this. If it fills with the faucets off and you are sure that when you turn the faucet off it is shutting off the water, then all I can think of is that the water is backing up in your drains stand pipe and filling the unit.
The unit's drain hose should not be sealed to the stand pipe.
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My problem is that the machine fills when turned off. What is the problem?[/COLOR]
If the unit fills when it is unplugged one of your water valves in the unit is leaking and you will have to replace the assembly.