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Replacement parts for General Electric GSD2200Z04WH Dishwasher | AppliancePartsPros.com

[COLOR="DarkRed"]Could this resistance cause a delay in draining as the valve is not completely open, or open long enough to completely drain.[/COLOR]
I do not think so. The way the drain works is that the wash/drain solenoid is activated for a couple seconds. The flapper valve is then moved to the drain position and the water pressure holds it there until the unit is empty.
If these solenoids are activated more than a couple seconds they will overheat.
Check that the solenoid plunger is pulled all the way down and stays there during the drain cycle.
Remove the wash arms so you can see the flapper valve and then manually activate the wash/drain solenoid to be sure it is closing all the way during drain.
Check the drain hose for any blockage. A common spot is where it is attached to the house plumbing.

It is a little late but for future reference. It is a good idea to lightly coat any plumbing seal/Oring etc with white lithium grease or plumbing grease before installing it.

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What about the drain pump?[/COLOR]
The unit uses the main pump for both wash and drain at least that is what the parts breakdown shows.