I just recently bought a 2008 Hunter 44 DS and the holding tank seems to be filling up daily. Also, the aft head bowl will fill up when the holding tank gets close to full? Anyone have any ideas or help would be greatly appreciated. Cheers
Holding tank filling up daily?
- Thread starter Bruce Merit
- Start date
Peggie Hall will no doubt weigh in on this and do whatever she says. 
What causes you to believe the holding tank is full?
If the symptom is fluids running back into the toilet bowl after flushing, there are several common causes.
In no particular order.
1) the vent line for the holding tank is plugged. When you pump the toilet it pressurizes the holding tank and that pressure forces the effluent back into the bowl.
2) the joker valve is shot. This is a one way valve that allows stuff to flow out of the toilet and into the lines to the holding tank. If the boat is new to you, this is a likely culprit. Even it if is not the cause, replacing it every year or two (depending on use) is a good idea.
3) the water intake line is siphoning seawater back into the bowl. Is there a vented loop between the pump and the bowl? To see if this is an issue, close the seacock after flushing. If the bowl fills, then the problem is elsewhere.
While we're waiting for Peggie to weigh in, pick up a copy of her book,
The New Get Rid of Boat Odors: A Boat Owner’s Guide to Marine Sanitation Systems and Other Sources of Aggravation and Odor it is a worthwhile investment.
What causes you to believe the holding tank is full?
If the symptom is fluids running back into the toilet bowl after flushing, there are several common causes.
In no particular order.
1) the vent line for the holding tank is plugged. When you pump the toilet it pressurizes the holding tank and that pressure forces the effluent back into the bowl.
2) the joker valve is shot. This is a one way valve that allows stuff to flow out of the toilet and into the lines to the holding tank. If the boat is new to you, this is a likely culprit. Even it if is not the cause, replacing it every year or two (depending on use) is a good idea.
3) the water intake line is siphoning seawater back into the bowl. Is there a vented loop between the pump and the bowl? To see if this is an issue, close the seacock after flushing. If the bowl fills, then the problem is elsewhere.
While we're waiting for Peggie to weigh in, pick up a copy of her book,
The New Get Rid of Boat Odors: A Boat Owner’s Guide to Marine Sanitation Systems and Other Sources of Aggravation and Odor it is a worthwhile investment.
yes and also the boat has a macerator as well.
The previous owner said he took it to the pumpout in the marina the day before I bought it. But when I was looking at it and also when the boat got surveyed you could smell the stench in the bilge. On our relocation trip I used the macerator and dumped it and have been doing that daily now as the tank takes less than a day to fill.
Both heads have anti-siphon valves but only the aft toilet bowl in filling up and they are both electric flush. The pumpout is located at the stern on the Starboard side, the same side at the aft head that is filling up. The strange thing is that that same toilet is also now periodically filling up even when the holding take gage says it’s only 3/4 full.
The heads are plumbed directly to the holding tank which is located under the galley floorboards. Not sure if any of this helps. Thank you for helping, Cheers
The previous owner said he took it to the pumpout in the marina the day before I bought it. But when I was looking at it and also when the boat got surveyed you could smell the stench in the bilge. On our relocation trip I used the macerator and dumped it and have been doing that daily now as the tank takes less than a day to fill.
Both heads have anti-siphon valves but only the aft toilet bowl in filling up and they are both electric flush. The pumpout is located at the stern on the Starboard side, the same side at the aft head that is filling up. The strange thing is that that same toilet is also now periodically filling up even when the holding take gage says it’s only 3/4 full.
The heads are plumbed directly to the holding tank which is located under the galley floorboards. Not sure if any of this helps. Thank you for helping, Cheers
@Bruce Merit your aft head joker valve needs to be replaced, close there through hull valve on the discharge and see if the tank continues to fill.
So far I haven't found any through hull valves for the heads. They seemed to be plumbed directly in to the holding tank
Maybe the holding tank was not emptied at the marina and maybe too much water used when flushing,what type of toilets do you have.
Nick
Nick
EDIT: I guess I should have asked Vacuum flush or pumped flush?
If you are going to the holding tank then you are not sending over board unless something is very messed up. On our 41DS there is a "Y" valve, to direct waste to either the macerator to a thru hull or to the waste tank. Here's link I am sure you will appreciate
https://forums.sailboatowners.com/i...resource-documents-archive-now-online.147756/
If you are going to the holding tank then you are not sending over board unless something is very messed up. On our 41DS there is a "Y" valve, to direct waste to either the macerator to a thru hull or to the waste tank. Here's link I am sure you will appreciate
https://forums.sailboatowners.com/i...resource-documents-archive-now-online.147756/
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Is the boat's water system connected to a hose at a dock? If so turn off the water and see if you still have the head filling up. If it stops the filling up, you need to service or change out the solenoid valve for the rear head. On my Hunter 50 the solenoid valve was under a removable panel in the aft shower. I just removed a s/s philipps head screw to take out the panel.
Unless your toilet(s) are designed to use onboard pressurized fresh water, there have to be below-waterline thru-hulls for the flush water inlet lines. Hopefully the PO didn't connect sea water toilets to the fresh water supply 'cuz in addition to the health safety issues that can cause, you're also draining your fresh water tank. So I suspect your toilet(s)--and therefore your holding tank too--are filling up with sea water. That needs to be stopped because it's putting your boat at risk of sinking in its slip while no one is aboard if that thru-hull is left open.
So there's a lot to deal with here! I'll be glad to help you get it all sorted out, but it's gonna require more detailed discussion than is practical in a discussion forum. So how 'bout sending me a PM that includes your email address and from there we need to go to the phone.
--Peggie
So there's a lot to deal with here! I'll be glad to help you get it all sorted out, but it's gonna require more detailed discussion than is practical in a discussion forum. So how 'bout sending me a PM that includes your email address and from there we need to go to the phone.
--Peggie
Since the holding tank was pumped out at the marina I have only used the macerator to empty the tank. Thank you for your information I'll check on the solenoid under the panel. I looked at it before and tapped it a few times as the previous owner said it might be stuck.
Thank you for the diagram I'll check it out further. I also just dumped my holding take again using the macerator and there is a large screw in plug on the top which I will try and open making sure it did empty. Thank you again
If you end up needing a new sender, we have them here:
https://shop.hunterowners.com/hp/monitors.php
https://shop.hunterowners.com/hp/monitors.php
Bruce, disconnect any water hose connected to the boat and turn off the pressure water pump. Operate the toilet water inlet valve till no more water comes out. Empty the aft toilet bowl. Wait 30-60 minutes. If there is no water in the bowl, the problem is not on the fresh water side of the plumbing. This will quickly tell you if the problem is the solenoid and/or the fresh water system.
There was no water hooked up. I've turned off the breaker for the water pump and also the head breaker as well and the bowl is now empty. Thank you for advice, giving it a shot! Cheers
