Head Problems

[David Howard]

As a new owner of a 1987 Hunter 31, I was shocked last weekend while out cruising to discover my holding tank had leaked and soaked the cushion under my V berth. There was about a quart of very smelly liquid soaking the cushion.
I had the gate valve turned to discharge and was wondering if this was the problem? When I activated the discharge pump a lot of bubbles,water and stuff came out of the boat. I continued with the pump for 5 min and then proceeded to clean up the mess. My question is what caused the problem? Several helpful boaters suggest that the holding tank was full and that caused the leak. I am still trying to rid the boat of the urine smell and have tried everything to trace the problem so it doesn't occur again. Someone suggested that all discharge through the head goes directly to the holding tank and there is no way to bypass the tank for direct discharge out of the boat. Does anyone know if this is true?
The diagram in the owner's manual is difficult to follow so I was wondering if it is possible to obtain a larger and more detailed version of the plumbing system on this vessel. Any help out there?
David

 

[Peggie Hall HeadMistress]

I suspect...

All those bubbles you saw when you opened the valve to overboard discharge are a strong indication that your tank vent is blocked, pressurizing the tank enough to cause it to leak around the fittings and/or the gate valve. The bubbles were due to the pressure being relieved.

The most common locations for a tank vent blockage are the vent thru-hull and the vent line connection to the tank, both the tank fitting and that end of the hose. Check both and scrape out what you find with a screwdriver or other tool. If there's a screen in the thru-hull, knock it out...it's not serving any useful purpose.

Do not use the toilet again till you've made sure the vent IS clear.

As for how to get rid of the odor: Clean up the spill, making sure to get ALL of it. Then spray every surface, nook and cranny in that area with Raritan K.O. Use it full strength, don't rinse...just let it dry. Take the cushion covers off...spray them down with K.O. and spray the foam with it too...use enough from both sides to penetrate all the way to the middle. Put 'em out in the sun to dry for the day.

And I'd replace that gate valve with good quality y-valve. Hunter used gate valves quite a bit in the 70s and 80s, but they've proven to be unsafe for use as seacocks and valves in any bellow-waterline connection. So if the seacock is also a gate valve, I'd replace it with a proper valve too.

 

[SeaRanch]

H31 Holding Tank Leaks

I had a H31, 1987 Model.
Search the "Hunter Owners" archives, you will find a wealth of info.
As delivered by Hunter, mine did not have a direct discharge, prior owner added a direct discharge and I added a "y" value to select deck pump out or overboard with a macerator pump.

Sounds like the "lid" on top of the built in fiberglass holding tank in the V berth leaked when the holding tank was full. As Peggy suggested check the vent line, if is were not blocked the overflow would have come out vent, unless the lid is not sealed.

If the lid is leaking you will need to remove it, very carefully, it is screwed and glued down with "fiberglass putty". Once removed, clean both surfaces throughly, removing all old putty and reinstall with "fiberglass putty" not 5200 or 4200! Use losts of putty and screw down tight, remove excess before it cures. After putty cures I would suggest that you "pressure test" the tank before refilling with "waste". Suggest Vinger to remove odors.

Steve Deon, who contributes frequently on the Hunter Owners Website, owned a H31 and is an expert on issues with the model, he may have some more ideas.
Great boat, good luck

 

[Steve Dion]

Re: H31 Holding Tank Leaks

SeaRanch:

Thanks for the vote of confidence. My guess is that the seal on the holding tank is broken and the screws are no longer holding.

We actually had the same problem on our H'31 water tank. I am not a fiberglass guy, so I tried a couple of different things like larger screws, butyl rubber seal etc etc.

I finally had to give in and had the entire lid of the water tank glassed in place. We put two inspection ports in the lid for inspection & cleaning of the tank. If you decide to do something similar, but sure that one of the ports in near the vent & outlet sides of the tank.

Another option is to completly remove the entire tank (which is glassed into the vberth) and replace it with a poly tank that would fit into the area. This would actually be a much better permanent solution and you could have the best of both worlds. You would never need to have that lid leak again and you may also gain some capacity too.

Ronco tanks are reasonably priced and can be now purchased on the SBO website too.

Be sure to check the vent line. We always back flushed ours every time that we pumped out.

 

[David Howard]

Thanks...Wow

What a wonderful site! I really appreciate all the feed back
When I purchased the boat in August, my surveyor insisted that the gate valves be replaced with bronze through hulls below the water line including the valve that drains from the vanity sink. This work was all performed at my expense at my local Hunter dealer. Do you think they made an error when they replaced the through hulls? Should I take it back to the dealer or will they even know what to do?

As a novice, I am still struggling with all the suggested advice except for the cleaning of the mess!

Where would I locate the vent for the holding tank? There is a two way valve below the tank the allows me to direct the material in the tank overboard. The macerator I assume is doing this and when operated, I see discharge from the boat so that must be working.

The top of the tank looks like it is sealed i.e. many screws and lots of sealant on the edges of the plywood. If I remove this lid will the tank now be open and exposed? Will this help me locate the vent so it can be cleaned?

I really appreciate all the suggestions but I am confused about how to check the venting for the holding tank? I do feel a bit stunned!

Thanks,

David

 

[sailingdog]

I hope you mean the gate valves were replaced with proper ball valves. You can't replace a gate valve with a through-hull...they're different parts and serve different functions.

The vent for the holding tank is probably a small screened fitting on the side of the hull, somewhere near the holding tank. It is probably a 1/2" or 5/8" hose coming off the top of the tank.

 

[Steve Dion]

David:

The "preferred" way to plumb the holding tank is to "always" pump everything into the holding tank. Then you can have a "Y" in the line to pump from the tank either overboard or at the pump out station.

If you replace the tank, you can use the existing vent line (new hose of course).

To clean the vent line, just run the city water hose from the thru hull and back flush the hose. Do this every time you pump out at the dock. Chances are that you overfilled the tank and some material plugged the vent line.

You may want to have one of your more experienced dock mates to look at your setup for their opinon.

 

[sailingdog]

You also will probably want some way of checking the holding tank level. I have a clear inspection port on top of mine. The most common way to clog a vent line is to overfill the holding tank. If you can monitor how full it is easily, then it makes it much easier to avoid doing that.