Jason,
I had the same problem with one of my pumps. Took apart the pump many times and put it back together per instruction. They sent me a new motor because the one I had didn't work. I ended up sending the pump back for repair, 25$ mailing fee. When I received it back they told me the gears were stripped, after 30 minutes of sporadic functioning. I also registered my product and they still requested a proof of purchase.