GE dishwasher not draining

Dishwasher Repair
1

Our dishwasher does not drain all the water out, it leaves about an inch of dirty water at the bottom. I have cleaned the drain out of the bottom of the dishwasher, it was full of dried soap. It worked fine for a few loads, then started not draining again.

I’ve checked the air gap for debri, but found nothing. Is there something else to check before a technician is called?

Thanks,
jason

2

Here are your parts
Replacement parts for GE GSD5620D00BB | AppliancePartsPros.com

A common problem with GE’s is the Piston and Nut, Item 564 in the “Body parts” section.
It is under the screen cover at the back in the tub.
It unscrews.
Might be a reverse thread, I am not sure about this.
If it does not seal it needs replacing.