When VFlush works...they are great. I have one of the 2 in my boat that is, however, making me crazy: VacuFlush VG 112 - the system with its own vacuum storage tank Symptoms over the last 8 or so weeks: = after flushing it would slowly leak off vacuum so that it came on and quickly pumped up enough to shut it off. Every 4 hours or so. = New duck bills. NO change. = 4 hours reduced to maybe every 2 hours = Got so bad that it just came on and would pump until it literally stalled and threw the switch in the panel = Replaced bellows. Cramped location only allowed me to get 3 of the 4 bolts holding the motor in place secured. Was rock solid nevertheless. = Here's the weird part...............it got fixed! The new bellows fixed it! = 8 days later.......it starts leaking vacuum again. Just like originally.....once every 3 or 4 hours it would come on. How crazy is that? It was working just fine and then slid into this failure mode. = 2 days ago......will hold vacuum for only 30 mins or so = We resort to turning the unit on and off at the fuse panel to use the malfunctioning forward head = Today...it pumps a bunch and doesn't seem to want to shut off at all I would replace the vacuum limiter switch in a heartbeat if I was sure it was the problem. Hate buying it at VacuFush overpricing retail and then discovering it isn't the problem. The hose from the commode to the pump haunts me. It is a potential leak spot. Replacing is a bear on both ends due to cramped quarters. Would do it........if I was sure it would make a difference. Having the unit work properly for 8 days suggests the hose it OK....yes? I am so stumped. Appreciate any thoughts.