Dishwasher grinding noise

My diswasher makes a grinding noise before and after each drain cycle. It is obvious to me there is some kind of valve is openning and closing to allow water to flow out. The bearings in that valve seem to be the source of the noise. I am just not that familiar with dishwashers in general to identify the specific part. Hope you can help. Thanks

The first thing I would do is remove the inlet cover (#506 on the break down diagram) and check for a foreign objects inside the filter sump.

If it would not help, remove the dishwasher from the cabinet, remove the drain pump (#325 on the break down diagram) and check for a foreign objects there. If the drain pump impeller got damaged - replace the drain pump.

Here are the break down diagrams for the GE dishwasher Model PDW7300G00CC

Gene.