Water to flush the head

Lisa

.
Oct 12, 2017
71
Catalina 310 323 Middle River, Md
Sailing in the Chesapeake doesn't present us with the blue water some experience. Over the years we have found that if we flush the head with the bay water and then leave that water sit in the lines till the following weekend the smell from the flush water is worse than the smell of a leaky head. So we have adopted a no bay water flush rule. We sometimes use the fresh water from the shower to flush, usually makes a mess. Most often keep a gallon jug of water handy for the flush, but that's just one more thing to secure when making way.

Since there is so much room under the boards in the aft bunk I got to thinking of putting a small 5-10 gallon water tank and attaching the head intake to it, creating a dedicated flush water tank, thus not using the fresh water from the main tank.

Anyone ever hear of anything like that?

Mike
 
Feb 20, 2011
7,990
Island Packet 35 Tucson, AZ/San Carlos, MX
Anyone ever hear of anything like that?
Something similar.
We use fresh water from jugs for the final flushes before we close the boat up for the week or month.
 

leo310

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Dec 15, 2006
635
Catalina 310 44 Campbell River BC
Have you tried flushing the head as the last thing you do before heading home after sailing with fresh water and use the bay water as per normal.
 
Jan 18, 2016
782
Catalina 387 Dana Point
Put a tee in your head sink drain. The drain -> tee -> the thruhull. Then move your head inlet onto that tee. To freshwater flush? Wash your hands then use the waste from the sink (or the last handwash, etc..). To seawater flush? open the thruhull. At the end of the trip just run some water into the sink and thru the head.

Easy. Cheap. Simple. Works really well. Frees up one thruhull. Saw the idea on one of Peggie's posts loooooong ago.
 

Lisa

.
Oct 12, 2017
71
Catalina 310 323 Middle River, Md
Have you tried flushing the head as the last thing you do before heading home after sailing with fresh water and use the bay water as per normal.
The smell comes from the bay water that sits in the hose from the thru hull to the head. Even if we do a final freshwater flush the water sits in the sea water flush hose. Then when we go down a week later and do a seawater flush, the first water out of the hose is rank. Once that flushes through to fresher seawater its all ok.
 
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Lisa

.
Oct 12, 2017
71
Catalina 310 323 Middle River, Md
Put a tee in your head sink drain. The drain -> tee -> the thruhull. Then move your head inlet onto that tee. To freshwater flush? Wash your hands then use the waste from the sink (or the last handwash, etc..). To seawater flush? open the thruhull. At the end of the trip just run some water into the sink and thru the head.

Easy. Cheap. Simple. Works really well. Frees up one thruhull. Saw the idea on one of Peggie's posts loooooong ago.
So if you open the thru hull it will suck water into the head rather than suck air down the sink drain to seawater flush?
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
The smell comes from the bay water that sits in the hose from the thru hull to the head. Even if we do a final freshwater flush the water sits in the sea water flush hose. Then when we go down a week later and do a seawater flush, the first water out of the hose is rank. Once that flushes through to fresher seawater its all ok.
Any water that’s full of critters that sits in the hose between the thru hull and the pump will go septic/anoxic when it sits. Bay, fresh, or salt. It all stinks eventually. Read up on Peggy’s forum here, and/or buy her book; lots of good ideas for making the head not smell.

It’s real easy to put a tee in the sink drain and use that for the head pump intake. Gives you the option of salt/bay water flushing for normal use, with a final flush of fresh water from the sink. Actually we just use fresh water just about all the time.
 
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Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
Put a tee in your head sink drain. The drain -> tee -> the thruhull. Then move your head inlet onto that tee. To freshwater flush? Wash your hands then use the waste from the sink (or the last handwash, etc..). To seawater flush? open the thruhull. At the end of the trip just run some water into the sink and thru the head.

Easy. Cheap. Simple. Works really well. Frees up one thruhull. Saw the idea on one of Peggie's posts loooooong ago.
You want to be sure that the water you use has no soap, dirt, or crud in it. Not a good idea to use the water you just washed your hands with.
 
Nov 16, 2012
1,037
Catalina 310, 2000, #31 31 Santa Cruz
So if you open the thru hull it will suck water into the head rather than suck air down the sink drain to seawater flush?
You may need to put a stopper in the sink drain when flushing with salt water, otherwise it just sucks air thru the sink drain, at least that’s what happens to us,
 
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Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
...Anyone ever hear of anything like that?
I assume you mean for the C310? I see a 323 in your info, so is that a Beneteau 323? I did the tee conversion on my B323. Then I had the problem of pulling air through the sink unless a stopper was in the drain. Sometimes operating the head pump would pop the stopper out of the drain! I measured between the thru hull and the seacock, then cut that much thread off the thruhull. Now there is enough seawater to make the head work, although there is still some air pulled through the sink. All in all, it is a good idea to do this conversion. At the end of a weekend, the last thing I do is clean the head and flush clean water from the sink, through the toilet. It is the organisms from the bay water that die in the rim of the bowl that stink. Flush them out and you'll be better off.
 
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Dec 2, 1997
8,709
- - LIttle Rock
Just pouring water into the bowl and flushing the toilet only rinses the sea water out of the bottom part of the pump and the toilet discharge line. To eliminate the odor from sea water that's been allowed to sit and stagnate, it's necessary to rinse the sea water out the whole system--toilet intake line, pump, channel in the rim of the bowl AND the discharge line. Water poured into the bowl would have to recirculate through the intake line to do that...and the last thing you want is a toilet that recirculates bowl contents. Several of you have touched on re-routing the toilet intake line to tee it into the head sink drain line....I think it may be time for detailed instructions. The following is an excerpt from my latest book (available from sbo.com see link in my signature):

If the head sink drains below waterline, it’s a simple matter to re-route the toilet intake hose to tee or wye it into the sink drain line as close to the seacock as possible because the connection must be below waterline to work. Or, if the head sink drains ABOVE waterline, do it in reverse—reroute the sink drain line to connect anywhere in the toilet intake line. Both hoses are typically the same size-- ¾” ID—on most boats. If they’re not, no problem...just make sure to buy a tee fitting that fits both sizes. .
How to use
You can use sea water to flush until you're ready to close up the boat and let it sit. After you’ve closed the toilet intake seacock in preparation to close up the boat (you do close all seacocks before leaving the boat to sit??), fill the sink with clean fresh water and flush the toilet. Because the seacock is closed, the toilet will draw the water out of the sink, rinsing the sea water out of the entire system—intake line, pump, channel in the rim of the bowl and the discharge line. . If your toilet is electric, be careful not to let it run dry…doing so can burn out the intake impeller.
It may also be necessary to keep the sink plugged except when in use, with a rubber sink plug or by installing a conveniently located shut-off valve in the drain hose. Otherwise the toilet may pull air through the sink when you try to flush, preventing the pump from priming.

Ok class...any questions?
Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
Jan 18, 2016
782
Catalina 387 Dana Point
If you read
So if you open the thru hull it will suck water into the head rather than suck air down the sink drain to seawater flush?
Not if it's under the waterline, and with a C-310 it will be. Maybe not heeled on port tack, but for the most part it'll be below the waterline and pump seawater if the thru hull is open.
 
Jan 18, 2016
782
Catalina 387 Dana Point
You want to be sure that the water you use has no soap, dirt, or crud in it. Not a good idea to use the water you just washed your hands with.
Why?

Soap? Smells good, not gonna stink in a week or so. I use some soaplike substance to clean my head, so soap is fine. Crud? How much more crud is going to come off your hands vs what comes out of the bay? The water I just washed my hands with is waaaaaaay cleaner than anything on the boat short of pure water out of the tank.
 
Dec 2, 1997
8,709
- - LIttle Rock
That depends on what you're washing off your hands. There's a big difference between the water you've just used to wash your hands after using the head and the water you've washed up with after working on your engine. But you're also overlooking that soaps and detergents break up grease and oil, stripping out the lubrication in your toilet pump...which can make it a bad idea to use a "soaplike substance" to clean the bowl. Moisturizing hand soaps and body bars have creams in 'em that can build up in the pump. Household chemical bowl cleaners, pine oil cleaners, and most "antibacterial" cleaners and soaps can damage the rubber parts the toilets. It all happens so gradually that you don't connect the problems with what you're flushing. Bottom line: it's best to stick with clean water to flush the toilet.
 

jviss

.
Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I'm wondering, how long does the bad smell persist? We've experienced this, probably not as bad as the OP describes, but when we get to the boat it has usually been pumped out, so I flush while adding the holding tank chemical, and any smell from "rank" water in hoses, etc., dissipates very quickly. Certainly not enough of an issue to redesign the plumbing or add a water tank.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
...I flush while adding the holding tank chemical, ... QUOTE]

Unless you flush the dead sea life out of the rim of the bowl, you are not getting rid of the source of the worst of the smell. When I change out my knot-meter paddlewheel, there are several types of little critters in the water that come in before I can place the dummy plug. Little mud shrimp, and thousand-legers or such. Those end up flushed through your toilet from end to end. Flushing only the bowl and pump does not cleanse the entire toilet. In eleven years I have NEVER had a complaint of toilet odors OR holding tanks odors- and I have NEVER used a deodorizer other than telling crew to spit the mouthwash into the toilet bowl. After the weekend, bit of vinegar helps clean the hoses.
 

KZW

.
May 17, 2014
831
Catalina 310 #307 Bluewater Bay, FL
So if you open the thru hull it will suck water into the head rather than suck air down the sink drain to seawater flush?
Fresh water flush. This is what I did when I swapped out the WC Head mate pump for the Raritan pump (I retained the WC bowl):
- Disconnect the raw seawater feed line to the head. Get a 3/4 plug and two hose clamps to seal off this line
- Buy four feet of 3/4 hose and a 3/4 T fitting. attach one end of the hose to the raw water intake of the head
- Run the hose up through the hole where the shower drain hose feeds in into the area under the head sink. It fit in my boat with no need to enlarge the existing hose
- Cut the head sink drain hose about six inches above the seacock. Insert the T (two hose clamps on each barb)
- Attach the hose from the head
To use:
- Keep the head drain seacock closed
- Turn on the fresh water pump switch and fill the sink to the desired level of water
- Use the shower head to put water in the head bowl, as desired
- To empty the head, turn the head valve to wet flush and pump (assuming manual head). This will draw water from the sink, through the T into the head, flushing the bowl.
- When no longer drawing water into the bowl, switch to dry flush and continue to pump everything to the holding tank
- Turn off the fresh water pump switch

This will use more fresh water. If you are on a long voyage, a stopper in the sink can be used (you need an air tight seal). Then open the sink seacock and you will draw in seawater through the T. That water will have tiny creatures in it. When they die in the lines, they will create oders. Flush the lines with fresh water once a day and you should be good.
Suggest you keep all seacocks closed unless they are in active use.
Not a good idea to put soap or anything else into the holding tank but human waste and product to promote aerobic bacteria in the holding tank. I defer to Peggy. Get and read her book!!!!


My before picture attached. I will try to remember to take the after picture and post.
 

Attachments

Dec 2, 1997
8,709
- - LIttle Rock
I'm wondering, how long does the bad smell persist?
It lasts until all the stagnant sea water has been flushed out of the inlet hose, pump and channel in the rim of the bowl....which is prob'ly about as long as it takes for you to pump the tank product to the tank. However, you're only replacing the stagnant sea water with "new" sea water...a sink full of fresh water flush cleans all the sea water out of the whole system.

There's another good reason: stinky water sitting in any hose including the inlet hose will permeate the hose. How long that takes depends on the quality of the hose used for your toilet intake line. That can also be prevented by flushing the sea water along with any micro- and not-so-micro-sea life out of the whole system BEFORE it can sit, die, stagnate and stink.
And there's one more benefit to be gained by a very simple $10 modification to the toilet inlet plumbing: if/when you find yourself in waters that are so skanky (as some anchorages that don't get enough tidal flushing can be) that you don't really want to flush with it, you can simply close the sink drain thru-hull and flush with fresh water via the sink while you're there.
 
Dec 2, 1997
8,709
- - LIttle Rock
Fresh water flush. This is what I did when I swapped out the WC Head mate pump for the Raritan pump (I retained the WC bowl):
I appreciate the plug for my book, but I would never have recommend anything that complex...You have to be an engineer.:dancing:
All that's really needed is a tee or wye in the sink drain line as close to the thru-hull as possible...reroute the toilet intake line to connect to that tee. When you want to flush with fresh water, close the sink drain thru-hull and fill the sink...flush.

As for the original toilet intake thru-hull, just close the seacock. It's now available to use for a washdown pump, HVAC water pump or anything else you've wanted to add but didn't want to put another hole in the boat.

Fwiw, several sailboat builders used to plumb their heads this way. It was a customer who owned a Tartan that was who put me onto the idea in the mid '90s.