New head and holding tank, will this sink my boat?
- Thread starter jemicha
- Start date
Interesting diagram
Never heard of a scoop intake being mounted on deck! That would let sea water in... and other stuff... out. Yikes.
:0
The gravity exit on a high-mounted tank, however, is common on some production boats nowadays -- as long as you have some legal waters in which to use it.
You're gonna need a deck pump out with its intake placed at the bottom of your tank.
Ten gallons is rather small for capacity. 15 or 20 would be much better, especially in the future where H.T. regulation is likely to be even more enforced on recreational boaters.
You Will need a vent fitting or you will not be able to pump into that tank.
My .02 worth,
LB
Never heard of a scoop intake being mounted on deck! That would let sea water in... and other stuff... out. Yikes.
:0
The gravity exit on a high-mounted tank, however, is common on some production boats nowadays -- as long as you have some legal waters in which to use it.
You're gonna need a deck pump out with its intake placed at the bottom of your tank.
Ten gallons is rather small for capacity. 15 or 20 would be much better, especially in the future where H.T. regulation is likely to be even more enforced on recreational boaters.
You Will need a vent fitting or you will not be able to pump into that tank.
My .02 worth,
LB
Yeah maybe that vent scoop would be too much, I was thinking a larger vent would be better to keep the air moving into the tank. Maybe I could just put two standard 5/8" vents in place to get a cross breeze. As for the pump out, would a Y valve below the tank do it and the discharge line do it?
I know that some experts like a duel-vent scheme for there tanks. I just have the one.
A Y valve is common on lots of boats, or like the plan adopted for the later Ericsons, have two outlets at the bottom, one for deck pumpout and one for discharge into the water.
There are some nice detailed head plumbing threads here -- do some site searches.
It's a challenge for sure -- smaller boats just do not have the the desired room/displacement for all the newer tankage and plumbing requirements.
Best,
LB
pooping in boats...
In my experience most boats I have worked on or just visited on that have holding tanks smell like...well..like poop.
I have never owned aboat with a holding tank. Ive always used porta-potties or a bucket with a seat attached to it. I know ...dealing with them sucks, especially after a week long cruise with my kids, however, i have extra storage where the tank would have gone, and porta-potties nowadays are pretty easy to deal with. I own an E-41 and the first thing I did was rip out the toilet, tank, and shower. There are composting toilets and a freind of mine uses a bucket and sprinkles some saw dust over when thier done and, voila, no smell. they can go up to a week wothout emptying the bucket. Eventually they do, at home where they compost their waste.And the saw dust thing works great, almost no smell, well... alot less than tanks.
Anyways good luck. It seems like you are into a big project. I too have taken on a restoration project. I have a photo album on this site somewhere... I should update it. Today I purchased diesel and engine coolant. I scheduled a launch date next week. Theres still some work to do, as always, but I can finish it on the water. A couple of sixpacks and a few friends and the rest of the hardware will be installed. See ya on the water....
In my experience most boats I have worked on or just visited on that have holding tanks smell like...well..like poop.
I have never owned aboat with a holding tank. Ive always used porta-potties or a bucket with a seat attached to it. I know ...dealing with them sucks, especially after a week long cruise with my kids, however, i have extra storage where the tank would have gone, and porta-potties nowadays are pretty easy to deal with. I own an E-41 and the first thing I did was rip out the toilet, tank, and shower. There are composting toilets and a freind of mine uses a bucket and sprinkles some saw dust over when thier done and, voila, no smell. they can go up to a week wothout emptying the bucket. Eventually they do, at home where they compost their waste.And the saw dust thing works great, almost no smell, well... alot less than tanks.
Anyways good luck. It seems like you are into a big project. I too have taken on a restoration project. I have a photo album on this site somewhere... I should update it. Today I purchased diesel and engine coolant. I scheduled a launch date next week. Theres still some work to do, as always, but I can finish it on the water. A couple of sixpacks and a few friends and the rest of the hardware will be installed. See ya on the water....
Nigel Calder's book has an illustration of one fairly similar to yours. I'm unable to reproduce the illustration so I will try to discuss it. One important difference is that Calder's toilet is turned 90 degrees so that its back is against the bulkhead, rather than against the hull. Accordingly, the tank is on the bulkhead as well, as opposed to being on the hull just below the deck as yours appears to. The idea is that the further to the center of the boat the tank is the better to avoid the boat's HEELING water line. Your picture shows the static water line but not the heeling, which is just as important.
As far as the vent, Calder's is centered on the top of the tank and extends to the hull, just below the hull to deck joint, rather than going up to the deck as yours does.
Finally, as for the pumpout, Calder's is also at the top of the tank, extending from the deck down through the tank to the tank's bottom. Also, it is attached to the tank as close to the centerline of the boat as possible (which puts it on the end of the tank as opposed to the vent which is centered on the tank).
Here are a couple of Calder's additional helpful hints:
1. Give the tank a large enough vent so that aerobic, rather than anaerobic, bacteria predominates for odor control. He doesn't give a size, but in his diagram the vent diameter looks about the same as the discharge line between the toilet and the tank. I don't think 5/8 " is what he had in mind.
2. If the line from the tank drain to the seacock at the bottom (the yellow line in your diagram) is straight enough, the line can be cleared from below by poking something through the thru-hull.
On edit: How wide are your side decks? In the photo it looks like they are quite narrow. Is that why you are mounting the toilet and tank against the hull rather than agianst the bulkhead?
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Thanks for both responses PDX and Vanfuego,
As for the portapotty, we had one for a few years and I am wanting to try something new (tired of carrying the full tank aft for a dumping). This may be more trouble in th long run and potentially messier though. We'll see.
As for turning the head so it faces fore or aft, my E26 just doesn't have the room to do so the side decks at the head are just wide enough to 'walk' toe to heel. But I do believe the tank will be well above the waterline even when heeled i.e., within 6 or 8 inches of the deck and towards the centerline the same amount to make it flush against the cabin wall. This is about as high as the fittings will allow, and I don't think I have ever seen the lee chains in green water on a tack before.
As for the large vent, I have a 1" threaded hole at the top of the tank, but I am unsure of what type of fitting to put over it. The intake scoop I though would serve as an air scoop and I thought it being on deck would reduce the chance of it scooping the ocean into my tank. I guess I could get it onto the cabin sides, but that wouldn't look quite so nice inside I don't think.
In Calder's diagram how does he extend the deck pumpout into the tank? Does he have a pipe that goes into the tank?
Thanks again for the responses,
Michael.
As for the portapotty, we had one for a few years and I am wanting to try something new (tired of carrying the full tank aft for a dumping). This may be more trouble in th long run and potentially messier though. We'll see.
As for turning the head so it faces fore or aft, my E26 just doesn't have the room to do so the side decks at the head are just wide enough to 'walk' toe to heel. But I do believe the tank will be well above the waterline even when heeled i.e., within 6 or 8 inches of the deck and towards the centerline the same amount to make it flush against the cabin wall. This is about as high as the fittings will allow, and I don't think I have ever seen the lee chains in green water on a tack before.
As for the large vent, I have a 1" threaded hole at the top of the tank, but I am unsure of what type of fitting to put over it. The intake scoop I though would serve as an air scoop and I thought it being on deck would reduce the chance of it scooping the ocean into my tank. I guess I could get it onto the cabin sides, but that wouldn't look quite so nice inside I don't think.
In Calder's diagram how does he extend the deck pumpout into the tank? Does he have a pipe that goes into the tank?
Thanks again for the responses,
Michael.
Yes, Calder recommends installing a pumpout tube down through the tank almost to the bottom and then attaching the tube to the deck fitting with a short length of hose.
I re-read Calder's section this morning. A couple of other tidbits:
1. On the hose run from the toilet to the holding tank, use rigid PVC pipe rather than flexible pipe.
2. Calder recommends that the base of the holding tank be located above the boat's maximum heeled waterline. If the base of the tank is below the boat's maximum heeled waterline, then the vent, pumpout, and toilet-to-tank hose fitting must all be above the boat's maximum heeled waterline. In this scenario, the tank will partially backflush with water when heeled on one side. He says this is OK if you are offshore and the discharge valve at the bottom is open--it will help scour the tank with saltwater and the water taken on will drain down through the bottom valve. I'm wondering about this for inland waters though where the discharge valve has to be kept shut. Seems like your tank could fill up sooner than you had planned on.
Thanks for looking into that diagram again to clarify. I think the rigid PVC pipe should be no problem as my brother-in-law owns a plumbing company in town here, and he is a wizard with that stuff.
As for the base of the tank being above the max heeled waterline, I don't think mine will make it. But as you say, the through-hull will be closed off most of the time, and I also may have a shutoff just below the tank to try to limit the amount of sewage sitting in the hoses.
And yes, I agree, the tank will fill up sooner than I imagined, especially since it is only 10 gallons.
Now to figure out how to plump in a pipe that runs fromt he deck fill through to the bottom of the tank...
Michael.
As for the base of the tank being above the max heeled waterline, I don't think mine will make it. But as you say, the through-hull will be closed off most of the time, and I also may have a shutoff just below the tank to try to limit the amount of sewage sitting in the hoses.
And yes, I agree, the tank will fill up sooner than I imagined, especially since it is only 10 gallons.
Now to figure out how to plump in a pipe that runs fromt he deck fill through to the bottom of the tank...
Michael.
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Randy Rutledge
Sustaining Member
A y in the discharge tube that goes the the seackck for overboard dumping would work without being a yvalve as the seackck is closed and the deck fitting would pull from the y when pumpoing out. The deck plate open or closed would couse no problem for dumping overboard.