I have a new Heartland North Country trailer and have been very happy with it except for one thing. The sewer tank is really hard to get to drain. It has happened twice and I think I figured out the problem. I tried to drain the tank one time and it would only trickle out. After attaching the water hose to the flush valve it finally started to drain. The second time I tried everything and it would not drain. I finally put a spray end on the end of the water hose and pushed it up the drain pipe and it finally started draining out (that was messy). After I got it drained and cleaned out, I put the water hose on the flush attachment and then went inside and looked down the toilet with a flashlight. I can see two to three pieces of plastic moving around in the tank. They are the pieces of the tank that were cored out for the toilet connection. Once is black, this is the core from the tank. The other is black on one side and white on the other. Not sure what that one is from. They are all perfectly round with a small hole in the middle so I know they are the core pieces. I think these pieces are covering the drain pipe end preventing me from draining the sewer tank. I would assume this should be covered under warranty. Any suggestions?<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>