Adding Water Tank for Fresh Flush
- Thread starter fizerocks
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- Joined
- Mar 5, 2001
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- 3655
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- 1,800
OK Jim, you're going to mount a 15 gallon tank, down below deck, near the through-hull, and have the toilet draw from it, correct? Before we get into the specifics of venting it, what method are you going to use to fill the tank? (answer with a little detail, if you can).
Once we've established that, we can have a look at how to vent it. All we know so far, is that the toilet will be drawing from the tank.
Once we've established that, we can have a look at how to vent it. All we know so far, is that the toilet will be drawing from the tank.
My inital plan is to just install the tank and hook it up to make sure the toilet pulls in the water. I thought for this I could just leave the lid open.
Once it has been determined the tank will work I wanted to add a deck fill with the access being in a storage locker.
I wondering what the harm would be if I could somehow expoy in a fitting for the vent and then connect a hose that would run into the bilge in the event that the tank overlflows.
- Joined
- Mar 5, 2001
- RO Number
- 3655
- Messages
- 1,800
(My inital plan is to just install the tank and hook it up to make sure the toilet pulls in the water. I thought for this I could just leave the lid open.)
OK, so far. The connection on the tank that the toilet draws from will have to be on the bottom, or at a low point on one of the sides of the tank - not on the top.
(Once it has been determined the tank will work I wanted to add a deck fill with the access being in a storage locker.)
It'll work. I'm not wild about the deck fill, although it can be done. The hose from the deck fill to the tank, and all connections will have to be water-tight. But where the problem comes in, is that the deck fill location will be much higher than the tank, so the vent will have to come up to that same level on the deck. Otherwise, the water "head" in the hose between the deck and the tank will run out the vent and into the boat. That's why I asked how you planned to fill the tank... If you were going to fill it manually with a bucket, right at the tank, no problem. But the deck fill poses a little problem.
(I wondering what the harm would be if I could somehow expoy in a fitting for the vent and then connect a hose that would run into the bilge in the event that the tank overlflows.)
If filling it from deck level, the tank will defiinitely overflow from the vent line. Depending on what type of tank you use, you may be able to drill and thread a hole in the tank, then add a thread/hose barb adapter to accomodate the vent line. It will have to be water-tight, and run up to the same level as the deck fill, preferably a little higher.
If it will be hidden inside a locker, what I would do is to add a fitting on the tank for the vent with a hose barb (maybe 1/4" - the vent line doesn't have to be all that big). Then attach the vent tube to the hose that goes up to the deck fill, with wire ties or even electrical tape. At the deck level, have the small tube come up through a hole drilled for it, about 2", then the tube would simply end - with the open end of it sticking up about 2". It will provide the necessary vent, and when you're filling the tank, when you see that the water in the vent line is about to overflow out the top, you'll know that the tank is full.
OK, so far. The connection on the tank that the toilet draws from will have to be on the bottom, or at a low point on one of the sides of the tank - not on the top.
(Once it has been determined the tank will work I wanted to add a deck fill with the access being in a storage locker.)
It'll work. I'm not wild about the deck fill, although it can be done. The hose from the deck fill to the tank, and all connections will have to be water-tight. But where the problem comes in, is that the deck fill location will be much higher than the tank, so the vent will have to come up to that same level on the deck. Otherwise, the water "head" in the hose between the deck and the tank will run out the vent and into the boat. That's why I asked how you planned to fill the tank... If you were going to fill it manually with a bucket, right at the tank, no problem. But the deck fill poses a little problem.
(I wondering what the harm would be if I could somehow expoy in a fitting for the vent and then connect a hose that would run into the bilge in the event that the tank overlflows.)
If filling it from deck level, the tank will defiinitely overflow from the vent line. Depending on what type of tank you use, you may be able to drill and thread a hole in the tank, then add a thread/hose barb adapter to accomodate the vent line. It will have to be water-tight, and run up to the same level as the deck fill, preferably a little higher.
If it will be hidden inside a locker, what I would do is to add a fitting on the tank for the vent with a hose barb (maybe 1/4" - the vent line doesn't have to be all that big). Then attach the vent tube to the hose that goes up to the deck fill, with wire ties or even electrical tape. At the deck level, have the small tube come up through a hole drilled for it, about 2", then the tube would simply end - with the open end of it sticking up about 2". It will provide the necessary vent, and when you're filling the tank, when you see that the water in the vent line is about to overflow out the top, you'll know that the tank is full.
Vic,
Below is a piture of the tank I planned on using. I've replaced the current fitting at the bottom of the tank with a straight 5/8" barb fitting to accept the line running to the bowl.
My main reason for running a deck fill is to avoid having to open the engine hatch each time I want to fill it.
Below is a piture of the tank I planned on using. I've replaced the current fitting at the bottom of the tank with a straight 5/8" barb fitting to accept the line running to the bowl.
My main reason for running a deck fill is to avoid having to open the engine hatch each time I want to fill it.
- Joined
- Mar 5, 2001
- RO Number
- 3655
- Messages
- 1,800
See if the tank is thick enough to drill and tap a hole in it, to accomodate the vent adapter fitting. That's a polyethylene tank, and the plastic is very "oily," making it difficult for any adhesive, including epoxy, to adhere to it.
If the plastic is too thin to thread you can use a 1/2" thru hull. Drill your hole in the desired spot and insert a few feet of string. Fish the string out the fill pipe with a coathanger. Then thread the line through the thru hull fitting and tie to a large nut or washer. Caulk the fitting and pull it into place with the string, and put the nut on to secure it. Pull the string back out the fill and you're done.
I've converted several 55gal plastic drums this way; sometimes it's necessary to trim the flange on the thru-hull so it'll go through the fill pipe.
I've converted several 55gal plastic drums this way; sometimes it's necessary to trim the flange on the thru-hull so it'll go through the fill pipe.
The tank is pretty thick. The current fitting at the bottom is threaded. We'll be heading to the boat on Saturday so I'll be doing the initial testing to see if this is going to work. I'll be sure to capture pics on the progress.
- Joined
- Mar 5, 2001
- RO Number
- 3655
- Messages
- 1,800
Yep, Todd makes 'em. You can save a couple bucks by getting it from Les:
http://www.boatfix.com/shop5/store/listItems.asp?strSearch=Fitting+relocation
http://www.boatfix.com/shop5/store/listItems.asp?strSearch=Fitting+relocation