We just bought boat, owner never used it he said… I think at one time it had an electric flush because it has switches on panel for head and macerate… it has a manual pump now… we tried putting water in toilet to prime it… it iflushed at least it looked like it did , you could see water coming down sides of the bowl and then the next time you go to pump it the handle had no resistance to it just went up and down with no water coming in… I don’t know if there is a valve that’s supposed to be open somewhere, but we did order a part Top Valve Gasket we will try that… but I’m wondering if there is a valve somewhere that lets water come in from lake to flush it… maybe it’s off…
Do you know where it would be?
Should be directly fastened to the thru hull fitting. Trace your intake hose and it should lead you right to it..