Yep. Pump is mounted vertically, with a ball valve on the outlet facing up.
I think I might be getting some vortexing from my dip tube. I actually saw it once create a whirlpool up to the surface sucking in air. Pretty cool actually. But the pump cavitates pretty much the entire time, even when its working, so I think there's more going on.
I'm brewing Friday, I'll try to remember to take a video with my phone and post.