Is a waste-discharge thru-hull really necessary?

[FredV]

OK, I know this may be a bit unorthodox, but I'm interested to know your opinions on this idea.

Based on my philosophy of "the fewer holes in my hull, the better", I'm starting to question the need for the thru-hull (forward starboard) for the head waste discharge. My thinking is that, since it can only be used while 3+ miles away from shore, it's really of limited use. So why not create some hose and pump arrangement that would allow emptying the waste holding tank into the ocean via the deck pumpout port, and thus eliminate the need for the thru-hull?

Obviously, the larger the holding tank, the less frequently it needs to be emptied, so since I'm replacing the old flexible tank anyway, I can install the largest tank that will fit.

Can anyone tell me what all I'm missing with this idea?

Thanks!

 

[kloudie1]

One thing to consider is where are ya going to store a smelly, drippy piece of 1.5" hose and connector..
If ya don't use your boat offshore much and are always close to a pump-out , there is no reason to have a through hull fitting for overboard discharge.

 

[onecoolair]

OK, I know this may be a bit unorthodox, but I'm interested to know your opinions on this idea.

Based on my philosophy of "the fewer holes in my hull, the better", I'm starting to question the need for the thru-hull (forward starboard) for the head waste discharge. My thinking is that, since it can only be used while 3+ miles away from shore, it's really of limited use. So why not create some hose and pump arrangement that would allow emptying the waste holding tank into the ocean via the deck pumpout port, and thus eliminate the need for the thru-hull?

Obviously, the larger the holding tank, the less frequently it needs to be emptied, so since I'm replacing the old flexible tank anyway, I can install the largest tank that will fit.

Can anyone tell me what all I'm missing with this idea?

Thanks!

My discharge thru hull valve was located in such an imposible to get too location and since everytime I pulled in some place to have tank pumped out the pump was always broken and was out of service. So I moved the discharge to the swim plateform. Make sure to put fitting at what would be top level of tank when full. Now I can use their hose and my masacrator to pump my tank. It also makes it easier to flush tank out with fresh water. And if offshore or in an emergency I still have the other option. :naughty:

 

[Ed Schenck]

On the Great Lakes you are not permitted to have an overboard discharge. When I bought my H37C that thru-hull was and is capped. The pump was also removed. I really haven't missed it even when I was three miles out in the Atlantic.

 

[DianaOfBurlington]

Necessity of through-hulls & seacocks

If you don't mind poop stains down the sides of the hull, you could provide an exit port well above the waterline, where theoretically a seacock isn't needed. Then you can figure out how to wash down the topsides whilst at sea.

As for myself, I consider the ability to evacuate the poop tank, for many, many reasons that may have nothing in common with the law, of paramount importance to seamanship. I may never need to do so; but if I have to, I want to be able to and with relative ease.

In many cases, having the through-hull is just necessary, whatever the perceived inconvenience. I don't have many on my boat but I have the ones that I need to have. And I know where they all are and, in accordance with my general rule, I can turn any one of them off within ten seconds of discovering I have a leak. If turning them regularly or in an emergency is of any more hassle than that, your boat has a systems-design problem and that's the thing that should be remedied.

 

[FredV]

OK, you convinced me - the thru-hull stays. But since it's currently fitted with a gate valve, I'll need to replace it with a proper seacock. I've decided against plastic (Marelon) so am looking at the bronze units by Groco, Apollo, etc.

Anyone have any comments - pro or con - for any of these brands? For instance, if there a REAL difference between the Groco and other seacocks which would justify their almost double cost?

 

[DianaOfBurlington]

Marelon.

FredV, I would go with Marelon and, with due respect, wonder why you ruled it out.

Benefits of Marelon:
1. Does not corrode; does not have to be bonded to other hunks of metal to avert electrolytic corrosion.
2. Needs no lubrication, is self-lubricating if you just work it through regularly (should be a weekly routine for all seacocks even on boats in storage).
3. Beds easily and permanently with 5200.
4. Is strong. RC Marine (whom Forespar absorbed) tested them by sliding a 500-lb weight the size of a toolbox down the side of the hull into it. The seacock was neither structurally compromised nor dislodged. When I first saw them I doubted their strength too, till I was told this.
5. Has the built-in safety feature of sacrificing its handle to excess force before the body of it becomes injured. You cannot put more weight on the handle than the body will bear-- the handle will break first.
6. Has interchangeable handle with various other sizes; so if you do break the handle just take one from another seacock.

Drawbacks:
1. Cost. Is much more expensive than otherwise attractive cheap brass valves (Apollo, etc).
2. Can't be confused with cheap brass, so you can't feel like you got a bargain and pulled one over on that annoying conventional wisdom that keeps trying to make the point that, for seacocks, 'cheaper' is 'less reliable'.
3. Has to come only from Forespar; and the OEM-grade ones (which I got, through channels :dance are better and faster/easier to install than the replacement-grade ones at Defender and WM.

Re: the OEM ones vs the replacement ones--
The replacement ones have the triangular flange with three bolt holes. The OEM ones have round flanges to be bonded into the hull at the construction phase. But here is the secret-- the replacement ones can be bonded without the screws and with no drilling of holes through the hull. There is more than enough surface area for strength. The screw holes are just the recommendation of the very wise folks at Forespar who know that 'replacement grade' means the seacock might not be getting installed by a professional boatbuilder. So they intend that the bolts will be enough in case the process specification isn't followed. Forespar issue very precise, very strict guidelines for OEMs about how they must be installed. For example, you may not take them apart or you void the warranty. However all parts to the OEM ones are interchangable and several times I have had to order a 90-degree tailpiece for one that was ordered as straight, or vice versa. I just phoned Forespar and they said, 'fine; you're an OEM; you do it; no problem.' They just want to know that you know what you're doing, because they really look out for you like that.

The process specification is to adequately clear the area of offensive gook, sand well down to bare 'glass, adequately solvent wash, and to bond using an adequate backing block (mine are fiberglass cut-outs from Cherubini CC20 cockpit sides) with 5200. And apply graded tension over the a period of enough time (do not tighten all at once but allow 5200 to cure under the flange). If you did that properly you wouldn't need the bolts. I wouldn't use them myself.

Caveat #1: the process specification relies on the OEM guy knowing what 'adequate' is here. If you know what you're doing, you can do it.

Caveat #2: the process specification does NOT permit silicone, Boat Life, butyl tape, Goop, or any product you can get at Lowe's. This is why there are different process specifications for the OEM ones and replacement ones.

...

As to the price difference between the Groco ones and the others, it is because they are proper marine-grade red bronze, NOT brass. I am not a metallurgical expert and usually rely on the manufacturer's specs to tell me which is which. But not all gold-colored metal-y things are the same. Yellow brass is a chameleon-- it's yellow when you put it on your boat and a week later it turns green. NO important fittings for rigging, plumbing or mooring should EVER be yellow brass (yes I know many people make them and buy them. Many people replace them too).

In the end, I really think that Marelon makes the most sense (and I do not get a kickback from Forespar for saying so :cry. Do consider them for this.

BTW, If you think the Groco ones are expensive, wait till you price the Perko ones!

 

[Mark Ferrick]

...
Benefits of Marelon:
2. Needs no lubrication, is self-lubricating if you just work it through regularly (should be a weekly routine for all seacocks even on boats in storage)...

DianaofBurlington, is working it through a hard requirement? If the boat is in storage over the winter, and you cannot 'work the valve' for a few months, would you still recommend it.

FredV, I would be interested in your final choices and the 'schematic' of the plumbing as I (hopefully) will be doing it later this year / early next.

 

[DianaOfBurlington]

Mark-- Marelon exercise.

Mark, I am sure many through-hulls survive a winter's worth of loneliness; but still I'd make sure to visit the boat regularly and to do stuff like that. I can't think of why they would not work even when cold and dry-- there shouldn't be any fluid in the lines for them to hold back during a winter that can go to freezing.

I'm sure you could rely on your spring commissioning routine to ensure they're all still working before you relaunch.

Call me OCD, but I just like to have inspection routines when in the water. Steve & Linda Dashew recommend a regular inspection cycle for everything on board to avoid being surprised by unexpected failures. A week's neglect can extend to a year's, you know.

Of course most people shut off all seacocks when they leave the boat after a day of sailing; and that will provide plenty of exercise for them.

Mind too that bronze ones need this exercise much more desperately than Marelon ones do.

 

[FredV]

JC - I actually think Marelon makes more sense than bronze and, if I didn't consider any feedback from others, would use it. On the other hand, the comments on various posts in this and other forums tend to slightly (only slightly!) prefer bronze over Marelon, albeit their primary complaint with the Marelon seacocks is that the handle broke. Also, my marina's manager, a friend and very knowledgeable guy, said "Why would you use plastic if you can use metal?"

That being said, your detailed and much-appreciated post on Marelon's OEM product makes a compelling case. And your explanation about the handle makes good sense. As I live on the boat now (on the hard) and plan to as well when she's launched, the simple maintenance procedure you described shouldn't be hard to do.

So, let me think a bit more about it, as I work in the forward cabin to replace the bunkbed arrangement with a true v-berth, stiffen and insulate the hull sides, add shelves, etc. I'll let you know once I've decided.

Thanks for your thoughts - after reading your book (twice!), I place great value on your input.

MARK - I'll post my progress with this here, but be patient - every task on my project list has taken at least 2-3 times longer than what I thought were really conservative estimates!

 

[Mark Ferrick]

FredV. I know that 2-3 times original estimate all too well :-(

 

[DianaOfBurlington]

Fred, Mark-- re: 2-3 times: Mine is more like 5-6 times! :neutral:

 

[Redbeard33]

Fred, Mark-- re: 2-3 times: Mine is more like 5-6 times! :neutral:

yeah no kidding, my original "plan" had me in the islands 6 months ago. But when I decided to refit this boat i promised myself not to cut any corners and it has snowballed into a pretty extensive project. One thing I have found to be helpful is to make a list of intended projects and put bullet points under each project listing each step, even ones that may seem obvious. Then when picking a project that evening or weekend, its a little easier to estimate time involved. you tend to overlook/underestimate the amount of prep work, cleanup, etc. It also helps you formulate a list of tools and supplies needed. But Even with this method I'm still around 4-5 times my original estimate.........