I didn't want to steal a thread as the OP was talking about a pligged head.
Just about to the point to call a serviceman.
Just to refresh:
Had to remove aft head to fix a water leak. I did seperate the bowl from the stand.
Sytem would pump up and both heads would flush as advertized. After system would pump up and shut off, about 3 minutes later it would start pumping for about 20 seconds or so and continue this cycle.
So far I have:
•Replaced bowl seal
•Replaced all 4 duck bills
•Checked all connections for leaks (with shaving cream)
So any further ideas?