460 LE Aft Waste Tank filling with water

Jun 16, 2014
3
Hunter 460 LE Port Huron
Only hours after a pump out, the head has not been used, the aft waste tank is full of water. Does anyone have any ideas why this may be happening?
 
Jan 12, 2011
930
Hunter 410 full time cruiser
what type of head installed, you have a siphon happening though it

clean the tank vent line and check to be sure you are leaving the head pump in the dry position after use (assuming you have a manual head, otherwise you need to check how water could be being allowed to flow though it)
 
Jan 22, 2008
597
Oday 35 and Mariner 2+2 Alexandria, VA
Sounds like a bad siphon break. Close the through hull on the aft toilet and see of that stops the tank from filling. If it does, than you wet dry valve is leaking and there is no siphon break between the pump and toilet or between the toilet and tank.
 
Jun 16, 2014
3
Hunter 460 LE Port Huron
Thanks for the input. I ran out out of time after I emptied the aft wast tank. I did however check the siphon break. In the process I dropped the duck bill plunger into tje Bowles of the boat. what I am assuming was the check valve. Of course I could not buy just the duck valve. I did close the thru hull. I will let you know what I find sunday when I return to our boat.
 
Jun 1, 2009
1,852
Hunter 49 toronto
Think I might know

Thanks for the input. I ran out out of time after I emptied the aft wast tank. I did however check the siphon break. In the process I dropped the duck bill plunger into tje Bowles of the boat. what I am assuming was the check valve. Of course I could not buy just the duck valve. I did close the thru hull. I will let you know what I find sunday when I return to our boat.
Not sure about your boat, but on the 49 there are mascerators on the boat with large in line shut off valves.
If you don't shut these, the holding tank fills with water when you aren't using the mascerator.