My Machine wont drain.

The motor will agitate and will spin when enough water is out of it, but wont drain.

The outlet hose will gravity drain so I dont think there is a clog anywhere.
When I fiddle with the controller I can make the pump come on, it hums but doesnt push water.

Is it definitely the pump, or could this still be a controller problem? My controller has some broken plastic and is tough to know what position it is in. I dont want to order a new pump and come to find it was something else? Any ideas?

washer spins slowly but does not drain water during cycle.