Ball Valves

[skipperdude]

So It is common Knowledge or not so common knowledge that a through hull fitting is straight thread as is a proper Seacock. Ball valves from the local home hard ware store are NPT or tapered.

The two don't work together.

Who has A ball Valve on a through hull in there boat?

I am working on my SAMS marine survey certification.

You would be surprised at how often I find this issue.

SD

 

[psneeld]

So It is common Knowledge or not so common knowledge that a through hull fitting is straight thread as is a proper Seacock. Ball valves from the local home hard ware store are NPT or tapered.

The two don't work together.

Who has A ball Valve on a through hull in there boat?

I am working on my SAMS marine survey certification.

You would be surprised at how often I find this issue.

SD

Lots of examples....sad but true.

I have seen manufacturers and big yards do it to.

Thus the comment in another thread about how in the marine inustry there's just as many knowledgeable cruisers out there as "experts", writers, marina guys, etc...etc. To blindly follow their lead is the blind leading the blind. That's why I find forums invaluable...not that all the info is right...but you often get leads that get you to where you want to be...sometimes it's someone in the marine field that actually ISN'T F.O.S!

Double check everyone's suggestions.

I just had to slam a boat broker because he was telling a friend of mine about registation/sales tax and how they work together in NJ...right off the DMV websirte and all..yeah right

We'll as usual I did my homework and printed up an actual NJ tax court case where it specifically laughed at the very thin connection the beauracrats have on the website between sales tax/registration of boats. For tax purposes, you follow the tax laws...not just some outline of money collection that the state agencies have agreed upon and put together a piss poor website of info/instruction to follow.

 

[HopCar]

I'm not sure it is currently true, but a few years ago the ABYC who sets standards for building boats in the US, approved of the installation of ball valves on thru-hulls. I once had a long discussion with one of their reps at a marine trade show about it. The jist of the discussion was that the boat builders wanted it that way. At any rate it was a step up from the formerly accepted practice of using gate valves on thru-hulls.

I know of at least one case where a 3/4" thru-hull broke off because something bumped into the ball valve screwed on to it. Interestingly it wasn't the threads that failed but the thru-hull itself. It look like there was a hidden flaw in the casting. If it had been installed with a proper flanged valve it would never have broken and if it did, it wouldn't have mattered.

Think of it as a quality indicator for the boat. If the builder went cheap on the thru-hull connections, he went cheap on other things as well.

Groco makes a neat little flange that solves the problem of mis-matched threads and allows you to use ball valves safely. Groco Flanged Adapter IBVF

 

[skipperdude]

The part you mention is a proper flanged seacock.
When a through hull fails it is usually the hull fitting that breaks.
That won't happen with a seacock. As it is flanged and attached to the hull. Where a ball valve on a through hull only has the thickness of the threaded pipe. (That is all a through hull really is.)
And they can leak.
Tapered threads and straight threads don't fit together properly.

SD

 

[Larry M]

Here's the set up with the adapter that HopCar's referring to:

 

[skipperdude]

Perfect. You have to cut off the thru hull so it beds at the base of the external threads.
this is the only way to use a ball valve on a boat.

In effect you are making a seacock.

 

[JAT]

Here's the set up with the adapter that HopCar's referring to:

That is the arrangement I installed in my bilge. I would not install a thruhull and then screw an valve on it...UNLESS....it was well above the water line.

 

[psneeld]

Here's the set up with the adapter that HopCar's referring to:

I just used 4 on my boat...got rid of all the original thruhulls, glassed in 6 holes and a ducer hole...replaced with the Groco adapters (which bothered me as they didn't screw together as far as I would have liked into the ball valves)...did it the Compass Marine way of bolting to pads epoxied to the hull. Pretty neat and great knowing the flexibility I hsve with replacing the valve portion with out a haulout.

 

[RickB]

Since ABYC was brought into this discussion why not tell the rest of the story.

A seacock is defined by ABYC as "... a type of valve used to control intake or discharge of water through the hull. It is operated by a lever type of handle usually operting through a 90* arc, giving a clear indication of whether it is open or shut, and is typically of the two following types:"

"Flanged Sea Valve - A flanged sea valve is a seacock with an integral flange used to individually and securely mount the device directly to the boat hull structure."

"In Line Ball Valve - A seacock designed to be supported entirely by the through-hull fitting."

ABYC references ANSI/UL 1121 "Marine through-hull Fittings and Sea Valves" as the standard. ABYC does not have a standard per se. ABYC has a standard that references strength of the installation as adequate to support a 500 pound load on the inboard end of the assembly "for 30 seconds without failing to stop water ingress."

ABYC standards state that the through-hull and seacock shall be connected directly (to each other) but does allow for a flexible connection if space is insufficient to do so. That means you can put a length of hose between the through-hull and the ball valve and still meet ABYC standards. If some silver hammer surveyor says otherwise tell him to whack himself with his hammer.

Flanged seacocks are not a requirement. To quote further from ABYC, "The American Boat and Yacht Council standards are guides to achieving a specific level of design or performance, and are not intended to preclude attainment of desired results by other means."

Bottom line, the device pictured above is NOT the only way to use a ball valve on a boat.

 

[skipperdude]

Rick have you ever seen a seacock fail due to impact?

Say a thru hull gets bronze desiese and becomes brittle I would think a properly secured seacock would withstand external forces much greater than just a thru hull that has the thickness of the wall of the treaded part.

ABYC may say it is safe But I wouldn't do it.

SD

 

[RickB]

ABYC will never say anything is "safe." There are ways to reduce risk but no boat will ever be "safe."

"... have you ever seen a seacock fail due to impact?"

Nope, all the boats I have owned or worked on have seacocks that are protected from that kind of abuse.

If you want to reduce the risk of breaking a seacock, protect it from falling objects and from becoming a stepping stone either intentionally or otherwise.

You can install a short piece of hose between the through-hull and valve and all but eliminate any chance of placing a bending load on it if you want. Cover the entire assembly with a box if you like but don't go around telling people that there is only one way to do something. Even ABYC acknowledges that fact.

If you are worried about de-zincification then check your fittings more often, know what you've got, and learn to recognize conditions before they become problems or worse.

 

[skipperdude]

I should have said. I Refering to the way I would do things.

SD

 

[psneeld]

I have seen several threaded bronze fitting fail when attempting to take them apart with little or no force. Luckily they were caught before failing in place (of course the "when they might have failed" in thatstatement is definitely an unknown).

While I agree many safety suggestions by ABYC are way over the top...I still think a true flanged and secured seacock is cheap insurance compared to a hole in the water you may have to deal with someday.

 

[RickB]

I have seen several threaded bronze fitting fail when attempting to take them apart with little or no force.

I suggest that those fittings were brass and not bronze.

Marine bronze alloys contain virtually no zinc so de-zincification is not a factor. If your fittings turn into sponge in seawater they are not made of bronze.

Beware the retail marine store labeling. Know what you are using.

 

[psneeld]

I suggest that those fittings were brass and not bronze.

Marine bronze alloys contain virtually no zinc so de-zincification is not a factor. If your fittings turn into sponge in seawater they are not made of bronze.

Beware the retail marine store labeling. Know what you are using.

I'm pretty sure they were bronze...just very old and I'm suspecting erosion from high sediment areas (several were a/c fittings) as you could see the high polish on the inside and they failed at threads which were paper thin...and may have been imperfect to begin with...they didn'y have that splotchy look of brass or the pinholing/pitting I'm used to with brass/copper in salt.

Not common I will admit as I know good bronze seems to last forever...but these could have easily sunk a boat.

Do you think that proper flanged seacocks are a waste of money and time?

 

[psneeld]

I suggest that those fittings were brass and not bronze.

Marine bronze alloys contain virtually no zinc so de-zincification is not a factor. If your fittings turn into sponge in seawater they are not made of bronze.

Beware the retail marine store labeling. Know what you are using.

I'm pretty sure they were bronze as they had no telltale dezincification symptoms...more like sediment erosion as they were paper thin and broke at the threads (several were air conditioning piping that were pretty old).

Do you think properly secured, flanged seacocks are the way to go or a waste of time/money?

 

[RickB]

(several were air conditioning piping that were pretty old).

Do you think properly secured, flanged seacocks are the way to go or a waste of time/money?

It sounds like it was a poor alloy of brass. Bronze and other copper alloys (CuNi or NiCu) have superior erosion resistance to steel. That is why there are used in high flow applications like condensers where there is more flow through a tube in a day than a yacht sees in several years.

I have written in the past: "Look at what you have in your boat and know what you are looking at." If those fittings were paper thin they got to that point because no one really looked at them or gave them a good thump once in a while.

I think "properly secured, flanged seacocks" are the greatest thing since oyster crackers but they are not the "only way" to handle moving water in or out of a boat.

I just have a real problem with recreational boat surveyors and owners getting stuck with the idea that there is a single "approved" method of doing something. By doing so they are squeezing themselves out of being able to afford to operate or maintain their boats with the least risk and best cost/benefit ratio.

Following some mantra imposed by dubious proponents is a poor alternative to taking the time to really learn something about how your boat works and why it works the way it does.

 

[Edelweiss]

It sounds like it was a poor alloy of brass. Bronze and other copper alloys (CuNi or NiCu) have superior erosion resistance to steel. That is why there are used in high flow applications like condensers where there is more flow through a tube in a day than a yacht sees in several years.

I just have a real problem with recreational boat surveyors and owners getting stuck with the idea that there is a single "approved" method of doing something. By doing so they are squeezing themselves out of being able to afford to operate or maintain their boats with the least risk and best cost/benefit ratio.

Following some mantra imposed by dubious proponents is a poor alternative to taking the time to really learn something about how your boat works and why it works the way it does.

------------------------------------
I couldn't agree more, Rick. The average recreational surveyor often expresses his personal opinion and not what the ABYC or any other governing body recommends. Unfortunately, the surveyor may be in a position to dictate his opinion, as you’re depending on his approval for your bank financing or insurance.

My last surveyor put me through hell over a similar issue, because he either didn't know that marine grade bronze contains no zinc or didn't care. His recommendation was to replace all of my bronze valves, which he described as "brass" with some type of nylon or plastic ball valve. He only backed down after a representative of my insurance company contacted him. My mistake was hiring him as a favor, I was told, "He is a good guy and needs the work" and me for not asking him some simple question.

How long have you been a surveyor? What is your experience in the marine industry? How many people did your company employ? Where did you get your training? Are you familiar with my make and style of boat? How many boats like mine have you surveyed. This guys qualifications and claim to fame was, "I built a 60' sailboat and ran a boat maintenance business (a one person marine handyman as it turned out). But I didn't ask those questions up front.

Don't be afraid to look at their qualifications, they may have minimal experience, took a class, and passed a test like this clown. If they look and sound like a turkey, either don't hire them or politely fire them and invite them to leave your boat.

Just my opinion
Larry B

 

[FF]

A genuine marine sea cock may not be "required" for someone agency approval ,

but if properly installed it sure is a great sleeping aid.

"Properly" installed is the goal , to me that means 3/8 quality bronze bolts , never SS, or tiny machine screws.

Not recommended , but YES , you should be able to stomp in it , with no harm.

On inspected boats the thru hull may frequently be required to be pulled , for inspection,. No big deal as it doesn't bother the sea cock a bit.

A cheap tool and rational bedding (not 5200) makes this a quick almost painless.job.

Real Sea cocks above the LWL? Why not?

There easy to service , can be relapped to seal almost forever , and are a cinch to winterize.

FF

 

[RickB]

On inspected boats the thru hull may frequently be required to be pulled , for inspection,. No big deal as it doesn't bother the sea cock a bit.

Pulling valves on the fire and bilge system as well as other internal seawater valves - not just seacocks - is part of the process of ensuring that they hold water when they should and have not eroded "paper thin" without anyone knowing about it until it breaks.

This is part of "knowing what you are looking at" on your boat. Events such as a paper thin fitting breaking off or a drive failure because a retainer was lost or non existent could have been prevented far more easily than installing a toilet paper filter or a polishing pump.

Make sure you can maintain what you put on your boat, as FF stated, that means avoid using 5200 on components that should be removed for inspection once in a while. If you want to use inexpensive brass fittings on some seawater systems (there are probably more than a few on everyone's boat already) go ahead, you can afford to replace them every year or two and you will probably never have a failure as long as you install them correctly - learn what that means. Don't use cheap stuff and expect it to last forever, but cheap new is way better than expensive and ignored.

 

[RickB]

Unfortunately, the surveyor may be in a position to dictate his opinion ...

Unless he is doing a valuation survey where an opinion is part of the product, the surveyor is not there to provide an opinion.

A surveyor should identify the vessel, state what is onboard, list obvious defects and damage such as broken windows or doors or soft decks, and when possible, if an item was seen to function or not. Period.

You can ask for a personal opinion but if the surveyor includes one on the report I think he or she has gone beyond his mandate. A surveyor might rightly report that the bilges contained oil, but he is rarely if ever in a position to state that the oil came from a leaking engine or transmission.

When a surveyor reports a "defect" he must be able to identify the function or standard it does not satisfy. If a surveyor cannot readily state the law, rule, or legal requirement to support his finding of non-compiance then he has no basis on which to call it out as a defect on the survey report. A surveyor is not a boat cop with the authority to nail an owner for reckless ownership.

 

[Budds Outlet]

I much appreciate the comments on this thread. This is the type of discussion that is so helpful to me. Both the discussion on the seacocks and also the discussion on the surveyor's role.

This prompted me to download the maintenance and parts sheet for my Groco SV series seacock that handles the waste discharge from the holding tank. I'd always been a little concerned about the small amount of seepage that occurred when the wingnut was loosened to allow the ball valve to turn. Now I know this is appropriate and to be expected.

This is a great forum. Keep the insrtuction coming!

 

[Marin]

This link has been posted before but for step by step, illustrated instructions on overhauling a seacock this site is great... Compass Marine "How To" Articles Photo Gallery by Compass Marine at pbase.com

The article you want is the first one in the third row down.

 

[ben2go]

This link has been posted before but for step by step, illustrated instructions on overhauling a seacock this site is great... Compass Marine "How To" Articles Photo Gallery by Compass Marine at pbase.com

The article you want is the first one in the third row down.