Thru Hull Question

[Rocket 69]

We are new to sailing, recently purchased a 1975 Dufour 24 as our beginner learn to sail boat. Great condition, new sails, the prior owner (couple years) didn't know about the Thru Hull age.


Got it hauled out, and due to the virus issue wasn't able to get it to where I could do the work. (After pressure washing and sanding, the bottom looked great, zero blisters)



New bottom paint has been done and thru hull/ seacock is going to be replaced.


When they hauled and pressure washed it, the (only) thru hull, which is unused currently. I believe this may have been for the sink drain, but it's currently not connected.


But I have never seen a thru hull with a "Flow Diverter" not sure what you call it. But it's going to require cutting it out to remove the old thru hull. Sorry crappy picture, I took a video after they pressure washed it and had to take a paused picture of the video.


Any ideas on this V-shaped flange over the outside of the thru-hull, and any special replacement issues? I have never seen one like this.


Also attached the inside view, old gate valve, maybe original. Don't know so that why they are both getting replaced.

[deblen]

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


Cheers/ Len

[SVHarmonie]

Ah, the 70's! Bad hair, worse clothes, and worst of all, gate valves as sea cocks.

A thru-hull fitting with a valve (of any kind) screwed on is not a proper seacock. Do it right with a through-bolted flange, and a straight thread valve that screws all the way on, and a tailpiece that bottoms out also. Something you could step on with your full weight and not worry about breaking off.

[Cheechako]

The divertor, (cant see anything clear in that pic) is probably to stop gurgling underway. Or possibly an attempt to stop water entering the sing on a heel.
Frankly, that thru hull looks pretty good, hard to say from a pic though.
I'd probably just screw on a new marine Ball Valve and call it a day.

[dougweibel]

If you are not planning to use the thru hole then why replace it? Just remove it and (properly) glass over the hole. That will require some grinding, so cutting away that "diverter" will just be part of the fiberglass work.

[Rocket 69]

Well they have replaced the thr hull in question, we are leaving off the wierd flow diverter, just a bit of glassing and fairing where we cut it off. The gate value looked ok, but the insides showed serious corrosion, glad we replaced it for piece of mind.


Better safe than sorry

[SVHarmonie]

Originally Posted by Rocket 69

Well they have replaced the thr hull in question, we are leaving off the wierd flow diverter, just a bit of glassing and fairing where we cut it off. The gate value looked ok, but the insides showed serious corrosion, glad we replaced it for piece of mind.


Better safe than sorry

Gate valves are NEVER “ok” as thru-hull valves. They were a bad idea back in the 70’s when they were used by lots of boat builders, and still are.

The issue is you can’t be sure they are actually closed, or open either for that matter! You tighten them as tight as you can, but all it takes is a bit of debris, or corrosion on the gate, and it is wedged open with no way of knowing you are still connected to the ocean. A ball valve is either open or closed, and you can tell which at a glance visually (almost) every time.