Pump Oil
You need to fill the pump with oil to the top of the plug. I use an hand oil pump to install it under pressure. You can get one at an auto parts store or Walmart. Fill the pump, wait a few minutes, then add some more oil, you can't overfill.
Also while your at it, check the impeller and wear ring, the clearance between the impeller and wear ring is no more than .040", you can check it with a feeler guage.
Lou