Ms Hall, On my previous post regarding my commode, I replaced the pump impellar last year and couldnt make the unit work properly with the old black ball inside the pump, I replaced it with a new one still wouldnt fill back up.
My question is this does the little black ball keep the unit primed,
if so would it be of any benifit to put a check valve in-line near the stand pipe that feeds the commode to keep the pump from losing its primed
This is not Ms. Hall but the answer is yes that ball helps keep the pump hose full so you are primed. Otherwise you can burn up an impeller running it dry. Many people take that ball out because it gets stuck due to raw water trash, but it is not a good idea. I guess you could use a check valve because that is what the ball is but the same problem would come with raw water in a check valve.
You may get advice to the contrary, but I installed brass check valves on top of the threaded toilet intake pipes that come through the hull. They made a big difference and water is always in the lines ready to flush, rather than draining back down between flushes.