Alan for Model Number MDB4000AWB I recently did an overhaul job on my 15 year old Maytag MDB4000AWB dishwasher. I replaced all hoses, gaskets, seals, and washers and installed the pump rebuild kit. It now runs like a charm, BUT, there is a loud hum that lasts about a minute before the water inlet valve opens and starts filling the tub with water. It does this before every fill during the wash and rinse cycle. It goes away when the valve opens and starts filling. There are no hums at all while filling or the motor is running during wash and rinse. Could the water inlet valve cause this? It seems to be the obvious culprit.
Answer Alan, Yes, the issue could be the fill valve WP99001359, after 15 years of service there could be an issue with the plungers and diaphragms inside the valve. It could also be due to a water pressure issue, so make sure you flush the water supply line before you install the replacement valve. Read More... Answered by AppliancePartsPros.com | Tuesday, May 20, 2014