I started a cycle with no dishes and realized that although I could hear the pump running, no water was being pumped through the middle or upper arms. There were no cracks or obvious leaks in the line that ran to them, so I figured it had to be the pump. The actual problem with the pump is that the impeller was stripped, so the pump ran when it was supposed to but wasn't spinning the impeller. Probably could have fixed it with some JB Weld, but figured I'd just get the new pump as this thing has seen daily use for several years. Replaced the pump with very few issues. It was a bit difficult putting the new pump into place in the rubber grommet, and you DO NEED a pair of pinch clamp pliers to use the clamps that come with it.