• Ahoy and Welcome to the New SSS Forum!!

    As you can see, we have migrated our old forums to new software. All your old posts, threads, attachments, and messages should be here. If you see anything out of place or have technical questions, please take a look in Forum Q&A for potential answers. If you don't find one, post a question and one of our moderators will answer. This will help others in our community. If you need more personalized assistance, please post your questions in Contact Us and leave a note with as much detail as possible.

    You should be able to login with your old credentials. If you have any issues, try resetting your password before clicking the Contact Us link.

    Cheers
    - SSS Technical Infrastructure

Advice: how do we feel about these seacock replacements?

A

alemon74

New member
In the hopes of sailing offshore and perhaps a solo transpac in the future i've started the process of refitting my boat. A recent survey recommended replacing some old seacocks. Took my boat to a local yard to get this done with a few additional maintenance tasks. Goal is to upgrade the boat in stages to get her ready for offshore sailing. I was surprised to see that they replaced my old flanged seacocks with inline valves on thruhull fittings. When I spoke to the yard and their manager they assured me that this was their standard and that they dont recommend the flanged seacocks and dont view them as necessary. I should have been more clear from the get go as to what I had in mind but I guess I erroneously assumed the flanged seacocks were the standard. My surveyor tells me that flanged or inline valves are abyc compliant but i was skeptical. Budget wise I cant afford to change course at this point so its done but I'm curious what the collective experience here thinks? Am i worrying unnecessarily? is this the common standard that other folks are seeing done? The actual installation work for what it is appears tidy. Appreciate any advice.

8A0CBBFF-AECD-4214-B5AA-A4E789DDA75C.JPG
 
First, I sympathize. I was in your shoes only a couple years ago doing the same thing. Second, it was only a couple years ago so I really can't say that I know what I'm talking about. All I can do is try and help with what I know but I can't tell you what I don't.

I took a picture of one of my installations (I was replacing the bungs and cleaning and servicing the valve) so you can compare, I did this install a couple years ago. I used the Groco IBVFs. So start at the Groco IBVF page at https://www.groco.net/products/valves-seacocks/flanged-valves/ibvf-flange-adaptor and then read the IBVF SERIES SERVICE SHEET linked on that page at https://www.groco.net/media/file/file/i/b/ibv-fbv-tech-blltn_5.pdf. I think this is so important that I attached it for when the links go stale. I think that document will help you.

You're going to find a lot of information and a lot of mis-information if you start searching on this issue. The best "Internet source" I found was here: https://marinehowto.com/seacock-thru-hull-primer/ so I'd at least start there. As you go down the rabbit-hole you'll probably first want to look at the ABYC take on this and you can get that in something called H-27 SEACOCKS, THRU-HULL FITTINGS, AND DRAIN PLUGS - 1465727039_H-27.pdf which you can get from ABYC by joining for a limited-time free membership. Basically your installation has to survive 500 lb (yikes) hanging on it for 30 seconds, but that is over-simplifying things and you should note the repeated sections telling you the installation should be done according to manufacturer instructions and that's why I put the Groco stuff here. I have called Groco a couple times, including for this issue, and they are supremely helpful. They get this question all the time, you will not be the first. If you call, I'd first research the difference between parallel and tapered threads. If you have a West Marine near you, go in and try screwing the various Groco parts they have together and you'll teach yourself a lot in 5 minutes. You won't be the first to stumble on the difference between NPT, NPS, as well as BSPT and BSPP. It's easy to get this wrong. I'm in the middle of a project with my cooling system drain on a Kubota block and right now I think both Universal and Beta Marine got this wrong, which is very hard to believe, but we'll see.

engine intake mounting.jpeg
 

Attachments

I subsequently sold the boat so it has a new owner now but on further research I think this is pretty shoddy work (by a well known yard here in the bay area). Speaking to groco, these would fail at <200 pounds of applied force and dont meet abyc standards. The IBVF setup that you used would deform and fail at >900 pounds of force and are SIGNIFICANTLY stronger. The boat yard assured me this is their "standard install" and they do it all the time. I guess its a great example of caveat emptor and yet another example of generally poor standards in the marine industry. Your install looks excellent btw. In future I would do the work myself or at the very least micromanage. These are probably fine for bay sailing but I wouldn't want to go offshore with them.
 
You must log in or register to reply here.
Back
Top