You sort of have to work it in stages.

1. Shut the pump off, open the pump basket, let everything drain and stabilize. Fill the pump basket and turn the pump on --JUST BRIEFLY! If the pump is operating correctly, and the filter and lines downstream are operating correctly, the pump basket should empty almost instantly.

2. After checking the pump, if it and the gear downstream seems clear, you'll need to test the lines and valves UPSTREAM of the pump. But, you'll need to post pictures before we could begin to tell you how to do so. Use Picasa, Webshots, Flickr or whatever, to post.