I done replace the water pump impeller made sure that the tube is sealing good. I took the lower unit back off and put a drill on it to make sure the pump was working and it pumped a good steam out the top of the water pump tube. it pumps but it not pumping like it suppose to It's spiting water and steam out and the water get really hot. I am running it in a 55 gal. drum. any help would be appreciated .