Hunter 44DS holding tank Deformed

Dec 7, 2014
6
Hunter 44DS Old Point Comfort
I have a 2005 Hunter 44DS, we purchased it new and have really enjoyed the last 10 plus years.
While enjoying the 80 degree weather yesterday we took some guests out on the boat. we had noticed a smell but didn't think to much of it until we returned. I lifted the deck plate over the holding tank, and the tank is now significantly deformed. bulging in areas and com[ressed in others. It almost looked like it had heat applied to it. no change in color just shaped weird. I cannot get the deck plate back on because the vent hose is now higher than the deck. Vent is working fine.
Any Idea what could have caused this?
is it possible to remove the kitchen cabinets to remove the tank?
 
Dec 2, 1997
8,708
- - LIttle Rock
What's the tank made of? Where is it located in the boat? What have you used in the tank? Have you changed recently or combined any products or chemicals? Anything new and different about the water in your area...has there been any kind of chemical spill that's run into the waters?

I lifted the deck plate over the holding tank, and the tank is now significantly deformed. bulging in areas and com[ressed in others. It almost looked like it had heat applied to it. no change in color just shaped weird. I cannot get the deck plate back on because the vent hose is now higher than the deck.


Since you asked if it's necessary to remove cabinets to replace the tank, I'm guessing that the tank is under the cabin sole (floor) and what you're calling a deck plate is actually a hatch in the sole. It would be very helpful if you can get pictures showing as much of the tank and surrounding area as possible.
 
Dec 7, 2014
6
Hunter 44DS Old Point Comfort
I will get pictures and post this evening. The tank is located on the starboard side under the galley.
Sorry, deck plates is what we called them on Submarines.
I don't believe we have changed anything. I try to make sure no chemicals get put in there. I read your posts when we first bought the boat and try to keep the good bacteria alive :)
 
May 24, 2004
7,129
CC 30 South Florida
It seems to me the vent could have been blocked while the contents were being pumped out. You indicate you cannot replace the hatch because the vent is now higher; could the hose have been pinched? Had you ever taken a look at that tank before; a lot of surprises from the manufacturing process are hidden out of sight. Is the tank busted or has the source of the smell been located? If there are no visible leaks I would seriously consider a blocked vent as the source of the smell.
 
Last edited:
Dec 2, 1997
8,708
- - LIttle Rock
That was my first thought too, Benny...but I want to see some photos before jumping to ANY conclusion. The boat is an '04 they bought new, so they've surely pumped out before...making a kinked vent line unlikely, but not impossible. I should have asked if they'd pumped out since using the boat before this cruise, either when putting the boat away after the last one or immediately before this one. That it's both bulging--which would be the result of serious pressurizing--and compressed, which would happen during pumpout is a strong indication of a vent blockage. If so, that the vent seems to be ok now may mean that the pumpout pulled out the blockage before the suction imploded the tank. In which case, he needs to count his blessings!

I definitely want to see the photos!
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Vent air flow in must > or = waste flow out.;)
Example...
An open vent is sized for 4 gallons/min of air in flow. Waste is sucked out at 5 gal/min. Oooops you get a vacuum on the tank, vent blocked / pinched or not. Chemical reactions, like adding Liquid Plummer or DrainO, can heat you tank and reduce its strength and make "steam" to tax your vent sizing.
Jim...