A small knob on the Cover and Stem Assembly broke allowing the lower washer arm to fall off every time the dishwasher cycled.

This is probably the easiest home repair I have ever done! I simply lifted out the screen exposing the Cover and Stem Assembly. It was held on by three screws. I removed the screws and lifted off the old part. (It had been there for over 10 years so I had to push a little to free it.) I then replaced it with the new part and replaced the three screws. It now works fine. One of those home repairs that is so simple but makes it look like you know what you are doing!