[TexFordD]

Pump runs. Soliniod activates. Flapper intact inside pump housing. Drain hose clear (took off of air check blew back into dishwasher} tried to drain at that point Water barely came out, found small plastic ball inside d/wshr. Not a check ball from valve? pulled screen base of inside. holes clear
This d/wshr has power tower. Pulled pump from unit everything seems normal there WT*? pump adgitates normally when in clean cycle but won't drain off.
I do apartment maintenance 23 years now. this ones got me stumped!

[denman]

Cannot find a parts breakdown to exactly match your unit but here are some units in that series. I am using the 00WW for reference.
Replacement parts for GSD4000N0066 models | AppliancePartsPros.com

You could try draining it into a pail. This will check if the plumbing drain is clogged. Just be sure to hold the hose securely in the pail and put a towel over the pail so water does not splash all over. A common place for it to plug is where the hose fits over the fitting into the plumbing drain.

Also could be the piston & nut (Item 564 in Section 2).
This is under the cover at the back inside of the tub. It unscrews.
Usually this just leaves some water in the tub after a drain cycle but perhaps it is totally shot.
It has to seal when draining or the water is directed back into the tub instead of out the drain hose.

[TexFordD]

Yep ran the hose into a pan and the water just barely comes out. blew back into hose and you can hear it 'girgul(sc)' inside.
Like I said and I've seen one other post here, that there was a small,3/4 inch, plastic ball inside d/w. Could this be part of a check valve?

[denman]

I do not believe that a plastic ball is used in this type of pump.