Leaking Ball valve

[Manateeman]

WOW. It’s ok to post the sort of correct way to fix a leaking ball valve because it’s been done by others and it seems to be ok because it’s pretty close to correct. Well it’s close to correct but not exactly. Good enough. The reason behind the recommendation is anecdotal. Not based on engineering. Based on an opinion...And what stands behind your opinion. I look into your “about me” and there is nothing there.
I post advice on the correct way. Period.
Advice based on real world expertise. Credentials. Experience.
I sincerely regret building some very popular oem boats. Balsa core, fin keel cheap light junk. I never thought anyone would take a beer can race boat to sea long after it’s short disposable life was over. There are those unbothered by selling an illusion that Ken Barbie and the cat blog is attainable on a son in a good old boat you repair with half assed methods. The world is covered with boatyards fill with broken dreams and cheap boats. You can’t keep a license to repair aircraft if you mismatch threads.
You cannot get a USCG inspector to approve the repair you recommend and I bet the same applies down under.
Let’s say the boat sinks. No one killed but some injury during rescue. And let’s pretend you are actually a professional boatbuilder. And it’s ...take your pick..civil or criminal. So they ask...yes or no...did the threads match?
You see there are two kinds of doctors in the world. Witch doctors ...lots of them and they do good often. Then there are Medical professionals with an MD.
Whatever floats your boat.
See, I stick my professional credentials where everyone can see them so they can make an informed decision about the worth of my advice.
Happy trails to you,
Captain Mark... his manatees are still rolling on the sea floor laughing.

[Honeymoon 26]

Originally Posted by Bill O

Looks like plenty of room to tap in a wooden plug or rubber stopper from the outside. Best would be to have a proper size of one of these expansion stoppers and tighten it up in spot.

Would be a good idea to have an appropriate sized pump handy, just in case.

A quick question, why is there a hose clamp near the nut of the thru hull?

The tie strap was to hold the handle in place, it leaked a bit more with it removed about 1 drip every 10 seconds now.

[Honeymoon 26]

Originally Posted by sailormed

Buy a "Seabung" and you will have peace of mind when unscrewing the ball valve. Soft rubber inserted from inside the hull in the throughull.

Unfortunately the valve is stuck shut.

[Dockhead]

Originally Posted by Manateeman

A poster has commented the thru hull might have had Teflon tape on it but I don’t see that from the photo. Teflon tape has nothing to do with what is going on here. In thus case, it looks like some idiot screwed a ball valve onto a thru hull directly. The thru hull threads are straight not tapered and the ball valve is tapered thread. The above poster is completely correct.
It’s a seriously bad installation.
Mismatched threads result in an incredibly weak joint...a few threads will jam up together...not screw together at all.
Any suggestion that you can reuse the thruhull will only result in a serious failure. Period. It’s just a matter of time and the corrosion keeps weakening the metal where it is jammed together.
A backing block will not cure this mismatch of threads. You cannot thread a tapered thread ball valve onto a straight thruhull...you can jam it together but that is not how tapered joints achieve a seal.
The uppermost threads of the thruhull are probably mashed and therefore it will difficult if not impossible to get the nut past them. This makes it impossible to screw down a Groco adaptor plate. If you do this in the water you need two very experienced divers who have done this before and an assistant, all the right new parts and a lot of luck...you need to keep the sea out while you hacksaw and punch out the old thruhull. Easier said than done. There is no way you are going to simply screw another ball valve onto this thruhull. No way.
Straight threads don’t screw into tapered threads. Period.
Happy trails to you
Captain Mark and his get out the crash pump manatees

Umm, he's in 'Straylia. They don't have NPT/NPS threads there.

They have BSP pipes there which thread together just fine! So this comment is entirely inapplicable outside of the U.S. Outside of the U.S., practically ALL ball valves are screwed directly onto through-hull fittings. This is normal and safe practice. Swans, Oysters, Halberg-Rasseys, are all built like that.

Nor am I even sure that the supposed incompatibility between NPT and NPS threads is not an urban legend, no matter how widely believed it is among cruisers. According to this: https://www.new-line.com/information...-compatibility it's ok to use male NPT with female NPS, just it won't seal without sealant. I did a little research and could not find ANY engineering literature which indicated that NPT male with NPS female leads to any weakening of the joint. I would be glad to be educated if I just didn't find it.

In Europe, they don't even make BSPT female fittings -- it is standard to use BSPT male with BSPP female. This type of joint (taper male, straight female) is European Standard UNI EN 10226-1; see http://www.sarm.am/docs/10226-1-2004.pdf

The maker of the best bronze underwater fittings, Maestrini, says this about it:

"Our products are usually threaded according to UNI EN 10226-1 standard, with taper external threads and parallel internal threads, where tight joints are made on the threads. Some articles, for obvious technical reasons, are threaded according to UNI ISO 228/1, with both internal and external parallel threads."

http://www.maestrini.it/eng/know-how.php?id=1

Are NPT/NPS joints different? I don't know.

[Dockhead]

To the OP: Don't listen to all the hysteria. There is no reason to be overly fearful about this procedure. Do of course have pumps handy, have help, and do this close to a place where you can be hauled out if necessary. Just block the through hull from the outside with whatever -- a hammered in wooden bung is best, but there are lots of ways to do it.

Then just carefully screw off the ball valve, Usually it will come off without twisting, if you're careful. You might want to tighten the locknut before you start. I've replaced all 15 of my ball valves and only twisted one of the through hulls -- and that was my own stupidity overtightening the ball valve trying to get it aligned better.

If the through-hull does twist and break the seal, it's not a big deal -- it will be a manageable leak, but then you will want to haul out. It's possible to reseal and retighten the through hull in the water, but it is a royal PITA to get it to seal. I would just haul out (or dry out).

When you have the ball valve off, check carefully for dezincification of the through hull -- use a small file. If you have the slightest doubt about it, you will want to replace the through hull at next haul out.

By the way, what kind of tides do you have where you are? Did you consider drying out or careening to do this?

[Honeymoon 26]

Thanks for all the advice, I am aware its a risky job in the water. I have jammed a bung in the hole under the boat however still concerned about the skin fitting letting go. I will be giving it some serious thought after reading these posts and still tying to organise the correct ball valve.

[Joli]

https://marinehowto.com/seacock-thru-hull-primer/

[Manateeman]

On page three of the document EN 10226 the third paragraph from the bottom clearly states mixing threads should not be done .
There are a lot of technical reasons why this is the bottom line.
I’ve worked for a number of OEM builders over a considerable amount of time. The boats have become faster and lighter. Just not stronger or more seaworthy because the operative rule is to find a cheaper and faster to install, solution.
My recommendation is to haul, replace with a Groco adaptor plate secured to the hull and use a Groco ball valve or find a commercial ball valve.
That will pass a commercial passenger vessel inspection in the USA.
I’d bet it would in most counties.
I don’t see anyone arguing this solution is incorrect.
I posted the correct method. It’s his boat and he can do what he wants.
Please refrain from lecturing me on how to build boats. The lack of credentials and experience are long past the amusement stage.
Happy trails to you
Captain Mark and his “actual professional boatbuilder” manatees.

[Dockhead]

Originally Posted by Manateeman

On page three of the document EN 10226 the third paragraph from the bottom clearly states mixing threads should not be done .

Sorry, it does not say that. It says:



That does not mean, do not use taper male with straight female -- which is a specifically approved joint. It simply means don't design a SYSTEM which has both taper and straight INTERNAL THREADS.

The entire document concerns joints made with BSPT male threads and BSPP female threads -- that is the EN 10226 joint, which is considered optimal for this application.

Originally Posted by Manateeman

My recommendation is . . . . That will pass a commercial passenger vessel inspection in the USA.

That is so yankee-centric. The USA and the world are not coextensive with each other. The man is half way around the world from the USA in a country with different standards.

Originally Posted by Manateeman

I don’t see anyone arguing this solution is incorrect.
I posted the correct method. . .

You posted ONE correct method, not THE correct method. ONE correct method, which is favored in only ONE part of the world. You are awfully assertive about your boat-building skills and qualifications. Are your skills and qualifications better than the whole engineering departments of Nautor Swan, Oyster, Halberg Rassey? And don't tell me that the only reason to go this route is because it's cheap -- those are all multi-million euro boats where cost is not the driver of the through hull/seacock solution.

There is more than one way to skin a cat, and the American way is not considered to be the only or even best way, in other parts of the world.

Ordering American-style parts from Groco in American not BSP sizes, from half way around the world, paying a fortune then waiting months for them, then having a system no one understands in Australia, is NOT a good solution for the OP. The better Australian boats have high quality bronze BSPT through hull fittings with high quality bronze BSPP ball valves screwed directly to them, just like all European boats have. That's the way they do it there, and there's nothing wrong with it.

[Joli]

Installing a tapered thread on a straight thread is wrong, no matter the company or country. I won't own a boat that has a ball valve spun onto skin fitting. By the tenor of this thread obviously others feel differently, oh well.

[Dockhead]

Originally Posted by Joli

Installing a tapered thread on a straight thread is wrong, no matter the company or country. I won't own a boat that has a ball valve spun onto skin fitting. By the tenor of this thread obviously others feel differently, oh well.

So no Nautor Swan for you, no Oyster, no Halberg Rassey, no Contest, no X-Yacht, no Wally, no Discovery -- the finest cruising boats made. Actually no non-American boat. So only Americans know how to put together underwater fittings?

[Joli]

Sure, I would own a Swan, HR or Oyster. And every single skin fitting with a ball valve would be replaced by a proper seacock before it left the yard. It's pure crap that a builder does this and says it ok because it meets some European ISO crap. You trust them if you want, I don't.

[Etalon]

For my sins I have spent many years building, specifying and building industrial systems with a lot of threaded pipe fittings. Only really low pressure water and compressed air, not hydraulics.

I will say though, mixing parallel and taper BSP is normal, as others have said. Taper male, parallel female.

The only problems we get is when someone accidentally orders parallel male and the fitting bottoms out before sealing.

Taper to taper will work, but you can get more adjustment with taper to p. Suggest using the thick gas rated ptfe, yellow rolls over here if you have a choice. Much quicker to use imo.

https://imgur.com/ofxHtQt

[Manateeman]

Mr. Dockhead. I looked at your “about me” profile. You own a boat, and it’s a nice, well built boat. I don’t know how the builder did the seacocks. I’ve visited a lot of boatbuilders world wide. There is quite a range of solutions to almost every component. The OP has a boat that is leaking. I posted one solution...I don’t think I stated it was the only solution. One poster believed it was possible to simplify the repair by blocking the thruhull and unscrewing the valve. Looking at the photo, I felt this was a bad idea .
I guess you take offense at the manner with which I responded. Interesting that we read the same publication and view it differently. Well that’s OK.
I gave the OP a solution which you have not stated is incorrect, just that other builders use a thruhull and a nut and a valve on top.
That’s not the most seaworthy method for a hull penetration open to the sea.
It’s not really a seacock at all...it is not the strongest method possible which is to attachable a continuous flange be it cast or welded, like standpipes, to the hull. Look at commercial ball valves and you will find flanged ball valves .
You could thru bolt them to a hull without any thru hull and it would be stronger than this ball valve sitting on top of a thru hull. I’m killing myself laughing because it’s real tempting to build both for a bench test.
OK so...maybe you got peeved with me because I got all “ show me your credentials “. Well I do have quite a resume with solid credentials. And I have asked posters on the forum to compare my credentials with others who post advice. Why wouldn’t this be beneficial to someone looking for answers.
You kinda got upset with me for what? Stating I’m a professional? It’s just facts. I am a professional Mariner and very experienced builder. So you go and say all that silly stuff about being smarter than a whole bunch of engineers. Did you ever think I might know them or that some of them might actually like the way I build boats?
Are you a boat builder. Are you a professional Mariner. Do you have post graduate engineering experience. Do you have other professional credentials in vessel safety or construction. Why do you get into all that “America” stuff.
Why the personal attack. I worked for Norway. I’m part Native American so believe me, I didn’t vote for trump. You can’t dislike manatees.
Happy trails to you kimosabi.
Captain Mark and his startled manatee crew

[Dockhead]

Originally Posted by Manateeman

Mr. Dockhead. I looked at your “about me” profile. You own a boat, and it’s a nice, well built boat. I don’t know how the builder did the seacocks. I’ve visited a lot of boatbuilders world wide. There is quite a range of solutions to almost every component. The OP has a boat that is leaking. I posted one solution...I don’t think I stated it was the only solution. One poster believed it was possible to simplify the repair by blocking the thruhull and unscrewing the valve. Looking at the photo, I felt this was a bad idea .
I guess you take offense at the manner with which I responded. Interesting that we read the same publication and view it differently. Well that’s OK.
I gave the OP a solution which you have not stated is incorrect, just that other builders use a thruhull and a nut and a valve on top.
That’s not the most seaworthy method for a hull penetration open to the sea.
It’s not really a seacock at all...it is not the strongest method possible which is to attachable a continuous flange be it cast or welded, like standpipes, to the hull. Look at commercial ball valves and you will find flanged ball valves .
You could thru bolt them to a hull without any thru hull and it would be stronger than this ball valve sitting on top of a thru hull. I’m killing myself laughing because it’s real tempting to build both for a bench test.
OK so...maybe you got peeved with me because I got all “ show me your credentials “. Well I do have quite a resume with solid credentials. And I have asked posters on the forum to compare my credentials with others who post advice. Why wouldn’t this be beneficial to someone looking for answers.
You kinda got upset with me for what? Stating I’m a professional? It’s just facts. I am a professional Mariner and very experienced builder. So you go and say all that silly stuff about being smarter than a whole bunch of engineers. Did you ever think I might know them or that some of them might actually like the way I build boats?
Are you a boat builder. Are you a professional Mariner. Do you have post graduate engineering experience. Do you have other professional credentials in vessel safety or construction. Why do you get into all that “America” stuff.
Why the personal attack. I worked for Norway. I’m part Native American so believe me, I didn’t vote for trump. You can’t dislike manatees.
Happy trails to you kimosabi.
Captain Mark and his startled manatee crew

Sorry if I seemed "upset" -- certainly I was not, and intended no offense And in no case categorically no personal attack, which I think you will see if you re-read my post. Certainly I have great respect for your experience and practical knowledge.

I was just pushing back against your rather categorical assertion that there is only one "correct" way to configure an underwater fitting. I will stand by my position that there are a number of "correct" ways to do it. What is widely favored in the U.S. is NOT considered the best way, in the rest of the world, and the OP is not in the U.S.

So nothing wrong whatsoever with your giving the OP one way of doing it. You explained it well and argued for it forcefully, and I don't argue that it's a good, strong way to do it. My ONLY objection is your claim that it's the ONLY right way to do it.

You can't prove that it's the only right way to do it, by stating that it's the strongest way, because it's not the strongest way. There are a number of stronger and safer ways to get seawater into and out of the boat, including welded up standpipes in cofferdams, which you see even in some yachts (KM builds expedition yachts like that), or seacocks in watertight compartments separated from passenger volume, like Dashew boats have. Or eliminate underwater openings with keel coolers and dry exhaust and composting toilets. There is ALWAYS some safer way to do it, but that doesn't mean that any of these is optimal. There is always a compromise between ultimate strength, cost, serviceability, functionality, safety, etc., in every boat system.

For example, you've built a lot of boats -- how many of them had five or more watertight compartments with real Lloyd certified watertight doors? I bet none. But this is much safer than building a boat with only one or two separate hull volumes, MUCH safer. How would you feel if someone came to you and said all the boats you built are crap, and the ONLY right way to build them is with five watertight compartments and real watertight doors? That is very much like what you've told the OP.

The finest boat builders in the world use the system which the OP has, and there is nothing in the world wrong with it. The system you advocate is somewhat stronger, but is a lot more complicated, harder to service, much much harder to replace, requires more holes in the hull. No one likes this system outside of the U.S., and it is simply not right for you to tell the OP in categorical terms that it's the ONLY right way to do it. It's not. In fact I wouldn't have them on my boat. To each his own.