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Replacement parts for gsd900g-01 models | AppliancePartsPros.com

Here is a link to a site with at least some info on GE's
http://www.applianceaid.com/ge-dish.html

This is a very basic unit.
I am assuming that it washes OK but does not drain.

Remove the kick plate.
You will see a solenoid on the left hand side of the pump assembly.
This is the wash/drain solenoid.
The way it work is that during wash the solenoid is deactivated, up.
When it is time to drain the timer applies power to it for a couple seconds, this pulls the solenoid down.
The solenoid is operating a flapper valve in the pump so that now the water is directed out the drain instead of to the wash arms.
The water pressure then holds the solenoid down (flapper is drain position) until empty then the springs pull it back to the wash position.

Check that this solenoid is activated when it should drain.
Cherck that the solenoid plunger moves up and down fairly easily.

Sometimes the timer can mess up and apply power to the solenoid for too long of a time, the solenoid then overheats and melts it's internal plastic. This jams the solenoid. So if it has overheated you will need a new solenoid and a timer.

Also check that your drain tube is clear.

Check that the sump is clean. Be careful as there is often glass in the sump.