Thru hull counts

[john61ct]

Wow. Remind me to do my boat shopping nearby wherever you happen to be!

[JPA Cate]

toilet, 2, one in, one out
head sink, 1 outlet
knotmeter, 1
engine, 1 inlet (outlet above water)
galley sink, 1 outlet

For a grand total of 6, each with their own timber bung tied on, except the knotmeter, which has an extra purpose-made plug.

[Simi 60]

Originally Posted by RaymondR

It's sort of hard to fit "miles of pipe work" into a 30' - 40' boat?

Even in our 60fter with two through hulls there would be 15ft of hose at most.

[Discovery 15797]

Wow...pretty amazing the diversity of descriptions of thruhull openings. Of course the OP stated thruhulls below the waterline. The only thruhull outlet that is below the waterline on my boat is the head discharge and the galley sink. Then there are thruhull intakes below the waterline for engine raw water, watermaker, head, and galley seawater. All other outlets (bildge, shower sump, cockpit drains, and emergency manual bildge pump) all exit at or above the waterline (esp. true of cockpit scupper drains).

And air conditioning...seriously? LOL

[Emmalina]

Spat the dummy years ago after skinning my knuckles too many times. One 2" through hull with a big strainer and sea chest everything else is above the waterline. Transducers are all in hull and all is fine !

[lituya1617]

The design of recreational boats, including sailboats, leaves the concept of reliability and safety aside while servicing glitz and gloss. Among the most unreliable of the traditional ways things are done are the thru hull fittings. Any discharge line should be ABOVE the waterline so it cannot leak. Such outlets also allow the boater to see if something is working properly, say the refrigeration heat exchanger (a better way to plumb this service is to incorporate the refrigeration/air conditioning heat exchanger into the keel cooler.) An intake line should tap into a central, very strong, thru hull with a large external screen and internal shut off valve that is easily accessed and closed. This intake should be in a sump with its top above the water line and equipped with a water alarm to reveal leaks immediately. There only needs to be one intake line for water rmakers, toilets, etc. Of course, the bilge should also feature a high water alarm. One major source of sinking caused by hull penetrations is the engine heat exchanger feed line. Commercial boats usually use a keel cooler because it is sealed and does not require an extra and unreliable, rubber impeller type pump. Also, I would not have an internal heat exchanger system on my sailboat because of the problems with a wet exhaust. Fitting failures with a wet exhaust are a great way to sink your boat; however, most boaters are unaware of the fact thaT the long-term effects of saltwater vapors invading the cylinders of the diesel engine are extremely damaging. It is downright stupid to put unprotected cast iron and steel in contact with the vapors of hot saltwater - as happens with the typical small sailboat diesel. Wet exhausts are popular but both unnecessary and dangerous. Properly muffled and with a tall enough exhaust pipe, a dry exhaust is extremely durable, quiet, and protective of the engine. Only the exhaust manifold itself need have a water jacket to satisfy the law. Beyond the manifold, simple insulation and a metal outside tube is sufficient to keep heat from being a problem. The outer tube is usually made large enough to create a draft that passively ventilates the engine room - another plus. Lastly, a dry and easily seen exhaust allows the boater to see the exhaust gasses and note any mechanical problems with the engine. You can tell a lot from what is coming out the exhaust. A hull is designed to keep water out of a boat and defeating this purpose with a bunch of thru hull fittings is kinda dumb. A composting or incinerating head is better than a pump-out type for many reasons, not the least of which is that plumbing salt water around inside the boat is hazardous. Galley sink drains have sunk a lot of boats, my father's for one. These should feature a spring-loaded shutoff valve that must be operated to drain the sink. This type of valve may annoy the cook but they beat swimming for shore in the middle of the night. Just like when you leave your house for any substantial period of time, you should shut off the water - all below thru hull fittings - every time you shut down the boat. The currently popular way of placing shut off valves in difficult-to-reach places only encourages people to fail to protect their boat by shutting off the thru hull when they leave. Having no hull penetrations below the waterline is the ideal but the shaft seal and the single thru hull for the keel cooler are pretty much impossible to avoid.

[NYSail]

Honestly, I have 14 holes below the water line not counting depth and speed..... If I had a leak I could check every one of them within a minute and find the leak. Also, not every fitting is open at the same time. No need to open the generator, the shower (2), the macerator (2), the frig drain, deck wash-down.... Yes Beneteau feels the more the merrier.

[boatpoker]

Originally Posted by NYSail

Honestly, I have 14 holes below the water line not counting depth and speed..... If I had a leak I could check every one of them within a minute and find the leak. Also, not every fitting is open at the same time. No need to open the generator, the shower (2), the macerator (2), the frig drain, deck wash-down.... Yes Beneteau feels the more the merrier.

Yes they do and each and every one of them is brass.

[john61ct]

Originally Posted by lituya1617

refrigeration heat exchanger

Water cooling is not even needed with modern gear, even in the tropics, air cooling is sufficient.

Just a suggestion, using hard returns and white space will encourage more people to read your posts.

[NYSail]

Originally Posted by boatpoker

Yes they do and each and every one of them is brass.

Yep..... and put in such a way that you need rubber arms and many angled fittings to replace. It will be my project next fall after I diagram a new layout and eliminate a few of these holes

[a64pilot]

I deleted a couple of post, because they quoted a deleted post, not because they were in themselves in any way incorrect, but of course the quote bypasses the deletion.

[MBraile]

I just found 11 Thru-hulls on my boat: 39 Ft

I dont have air conditioner
no Gen Set

do I really need this ? or should I close some

https://imgur.com/a/Qrdd0Hv

Thanks

[OldManMirage]

I don't think it really matters how many thru-hulls you have but what is their condition ? It's not like there's some award for the least number.

Are we talking just those below the waterline or do we include the ones above the waterline too ? And what do we mean by "fail" ? Did it suddenly separate somehow and cause the boat to sink ?

In all serious though, it's not the number of them that matters. So what if a boat has 20 or 30 or 100 ? If they are all well made and in good shape it's not like they are suddenly going to all fail at the same time is it ? Or at all for that matter. Why do people feel like a thru-hull is a ticking time bomb ?

I've had at least a dozen boats both power and sail over the last 40 years, in various states of condition, and I've never had a thru-hull fail. Never. I worked for a broker when I was younger and saw hundreds of boats, some in horrible condition and still never saw a thru-hull fail.

I'm not saying it doesn't happen. But I'd say it must be pretty rare. Like UFO rare because I've never seen one of those either.

I'm not trying to start anything here, I just don't get it.

I'm sure people will start piping in with their stories of failure. I just don't have any myself, and I don't know of anyone who does.

[pcmm]

I started out with 22 thruhulls on my 41ft boat. there were ones for refridgeration, Air Con, generator, Head discharge, water pickups and a few I didn't know what they were for. I glassed closed 16 of them! now just have cockpit scuppers (2) sinks (3) and engine intake (1) All now on bronze flanged seacocks on bonded in G10 Flanges

[TeddyDiver]

Originally Posted by OldManMirage

snip... and still never saw a thru-hull fail.

I'm not saying it doesn't happen. But I'd say it must be pretty rare. Like UFO rare because I've never seen one of those either.

...snip

You see only the boats afloat. Once it failed and sunk you're not to see it fail either.