Best seacock for saltwater intake in head

[S/V Alchemy]

Not directly applicable here, but I've migrated to Marelon (it's a steel boat) and will be replacing my standpipe and 3/4" tee-offs for Marelon for A/C, head intake, engine intake and watermaker after haulout. I am pleased with them so far. I used the necessary straight threads (NPS) on the SS nipples and put on Marelon ballcocks for the head and galley drains. They spun on with plenty of depth over Teflon tape and pipe dope and haven't leaked a drop.

[Scout 30]

I think any thread on seacocks is a good thing. The main this is to make sure whatever you have is a true seacock & not something from HomeDepot. As long as you work them regularly & keep an eye on them they should be good.

[HopCar]

Originally Posted by Scout 30

A well built tapered cone seacock that is lubricated annually, and protected from galvanic or stray current corrosion is a forever investment.

Ball valve seacocks are also a forever investment at half the cost.
They don’t need to be lubricated but so many people think they do that Groco has started installing zerk fittings to make it easy. They never need to be disassembled and honed like tapered cone valves.

I sold hundreds of tapered cone seacocks but when I had my boat built, I installed Apollo Ball Valve Seacocks. Thirty years later they still work fine. Never lubricated.

[HopCar]

Originally Posted by Cheechako

The one bad thing about ball valves is many have a small opening through the ball. If you want true size and flow you need to buy up a size. Go look at the bore through the ball on say a 1" ball valve. It's probably something like 3/4".
There may be true to size ones out there though... Like Scout said, a tapered cone seacock is a lifetime investment. :>)

Both the Groco BV and FBV series seacocks are full flow.

[Scout 30]

Originally Posted by HopCar

Ball valve seacocks are also a forever investment at half the cost.

I don't agree. Any corrosion affecting the ball will cause this type of seacock to leak and they cannot be repaired. Being able to hone a tapered cone is actually a good thing. The whole process of dismantling, honing & greasing a tapered cone seacock is very short & simple.

[HopCar]

Originally Posted by Scout 30

I don't agree. Any corrosion affecting the ball will cause this type of seacock to leak and they cannot be repaired. Being able to hone a tapered cone is actually a good thing. The whole process of dismantling, honing & greasing a tapered cone seacock is very short & simple.

Never saw one fail because of a corroded ball.

[Training Wheels]

I had one tapered cone seacock, hated it. Replaced all my seacocks with trudesign.

[a64pilot]

You guys really hone them?
I don’t do anything at all to mine, and at 30 yrs they are still fine, without any maintenance

[model 10]

[QUOTE=HopCar;. Thirty years later they still work fine. Never lubricated.


Does that mean we can toss the rusty grease fitting and put a plug in the hole? I could never get any grease in it anyway.

[CarlF]

I've had Spartan. Will last forever but I did the recommended annual maintenance that takes a while to get it just right (not too stiff or leaking) And regular inspection for galvanic corrosion on the bronze. Very expensive.

Groco. Will last a long time but you do have dissimilar metals inside to worry about a little. Also should be greased annually and check for galvanic corrosion on bronze. If not regularly used they often get stiff and may require a few hammer taps to get them going if they are at a hard to reach location.

I now use the Forespar "OEM 93 series" (pictured above - recognize by the four bolts on the top). You are supposed to use the Forespar tailpipe that comes with it. No metal to worry about. Handle very strong (unlike the horrible handle on the other Forespar seacocks which also swell and stiffen - they should be taken off the market). I never grease mine or do any maintenance just "exercise" twice a year. Turning it is smooth and easy. So easy that you can attach a push-pull rod to the handle to open and close remotely. As mentioned do use the 1" instead of the 3/4" as the thick plastic narrows the passage a bit. You don't have to be an OEM to buy them but have to look around a bit. Passes the ABYC 500 lb side load test

https://www.youtube.com/watch?v=SLvLKnzop-0

The little white plastic fitting on the handle can be removed and used to plug the tailpipe by diving under the boat. You could then change the seacock with the boat in the water (although I've never had to do this).

[HopCar]

[QUOTE=Ecos;2673507][QUOTE=HopCar;. Thirty years later they still work fine. Never lubricated.


Does that mean we can toss the rusty grease fitting and put a plug in the hole? I could never get any grease in it anyway.[/QUOTE]

Yes, in fact Groco used to warn against putting a grease fitting on their ball valve seacocks. The theory was that you could create enough pressure to blow the seals. Apparently that didn’t happen. I still wouldn’t give it more than a quick squirt or at least partially close the valve so trapped air and excess grease can escape.

[Alita49DS]

Trudesign. Absolutely no contest. The others are all old technology.

That includes the American Marlon. The New Zealanders have nailed it.

[Terra Nova]

Originally Posted by HopCar

I think the Groco BV series are the best seacocks on the market...

Seconded.

[ramblinrod]

Originally Posted by chuck g

Looking for recommendations on the best 3/4" seacock for this application, which involves more use of the shutoff handle than any other seacock on my boat. I'm leaning toward the Groco BV-750 ball valve, which appears to have a particularly rugged handle, but also considering the Spartan barrel valve. My original 41-year-old valve is showing its age. Thanks in advance for any wisdom --

NONE!

Put a Tee in the head sink drain hose just below the waterline and bush down to 3/4” for the head intake ball valve.

Eliminates a thru-hull penetration and to winterize the head just close the galley sink discharge thruhull, pour antifreeze down the sink and pump it through the head. Eliminates the need to disconnect the head pump intake hose to winterize.

[old frog]

Originally Posted by chuck g

Looking for recommendations on the best 3/4" seacock for this application, which involves more use of the shutoff handle than any other seacock on my boat. I'm leaning toward the Groco BV-750 ball valve, which appears to have a particularly rugged handle, but also considering the Spartan barrel valve. My original 41-year-old valve is showing its age. Thanks in advance for any wisdom --

In my opinion, it depends upon the boat, boat construction, sea valve location within the boat, the boat's future intended usage, the boat's electrical complexity, and where the boat it moored and that environment, etc. There is no one one "best" sea cock.

Personally, & assuming the boat is FRP, I prefer the traditional flanged bronze coned sea cock (several manufactures) positioned in the boat so that it is easily accessible & serviceable. When installed via monel bolts, bolted to the hull skin (w or w/o the through hull) properly bedded to the hull, these will last almost for ever. I am also of the opinion that they are the strongest impact resistant valve installation & most forgiving vis-a-vis internal abrasion as they can be serviced.

However, as the above boat becomes more electrically complex (Ie. bonding systems &/or moves into a mooring environment where the is a probability of stray current fields within the area/mooring basin, (especially if the boat has a full bonding system) I personally believe the advantage shifts to one of the dielectric composite valve systems. As the suspended abrasives (ie. sand, etc.) in the water increases, I am of the opinion that the advantages begin to shift away. If the boat is wet moored in an area subject to freezing and the sea valve is one that must remain open (ie: cockpit drain), the advantage shifts back to the "traditional" bronze valve.

While I am not a fan of the ball valve mounted on solely on a threaded through hull (assuming proper thread compatibility & thread engagement), I am of the opinion that the advantage shift to them when the valve is located in a restricted area where it is not easily serviced (as is so common on most production boats) and there is nothing in that space that could shift & place excessive loads on the valve. The advantage of the ball valve is that it requires little maintenance & has a compact size so that it is easy to remove & replace should it develop problems.

All valve have their merits & issues. All, like everything on a boat, require periodic maintenance & inspection.

Don't get me started on the above water line valves. IMHO, the plastic though-hull above the waterline without some method or valve to close the hull penetration when the through hull fails is an problem waiting to happen.

Just my $.02.