I have a bad thru-hull on my boat. The stem that turns the ball is broken with the valve in the closed position. I grease all 8 of my thru-hulls yearly but after 25 years some of them are now hard to turn. The one under the galley sink is VERY hard to turn. My question is, "should I replace all of them or just the one that has malfunctioned"? Is there any consensus on the lifespan?
Thru-hull ball valve replacement on 40.5
- Thread starter David Knauer
- Start date
Well my 2007 H-36 has really six main thru hulls that I use regularly and I just replaced 2 of them as one was broke and one was very iffy so I replaced them both and my backing plates were very spongy so all new backing plates and 2 new values replaced and mine are 2 part so the values unscrew from the thru hulls and the other 4 just needed grease and they working great but if they are hard to use try grease but if still hard it’s only a matter of time before they will need replacing and better to do now than later.
Nick
Nick
David- I feel your pain. I suffered with the galley valve that was extremely hard to turn. Last year I replaced all of my sink hoses (OEM hose not rated for below water line use- see my post about that issue) and for the galley I needed to replace the straight hose barb with a 90 degree ell. I ended up breaking the thru-hull seal so I just removed the entire valve and thru-hull. I replaced the backing plate with a 1/2" fiberglass circle that I epoxied to the hull with West System. I then used a Groco thru-hull adapter with NPS threads on the bottom and NPT threads on the top for a proper match to the thru-hull threads and the ball valve.
I was going to replace the ball valve because it was so hard to operate, but I found that new ones were even harder to operate! So I soaked the valve in PB blaster for a couple weeks working it at every opportunity. Finally, it began to operate freely.
Now I can open and close the valve with the tips of my fingers and it is now the easiest operating valve I have.
I have never been successful in greasing any of the Apollo valves. I have tried several years with different kinds of grease and oils and nothing has worked to free them.
I have no idea how long these valves are expected to last, but based upon the amount of work to replace one with the right backing plate and thread adapter, I am inclined to replace on an as-needed basis. If I lived close to my boat and could work on this over the winter, then I might make a upgrade project and replace or re-work all of the valves.
The pictures below show the original galley hose and thru-hull and my new installation-
I was going to replace the ball valve because it was so hard to operate, but I found that new ones were even harder to operate! So I soaked the valve in PB blaster for a couple weeks working it at every opportunity. Finally, it began to operate freely.
Now I can open and close the valve with the tips of my fingers and it is now the easiest operating valve I have.
I have never been successful in greasing any of the Apollo valves. I have tried several years with different kinds of grease and oils and nothing has worked to free them.
I have no idea how long these valves are expected to last, but based upon the amount of work to replace one with the right backing plate and thread adapter, I am inclined to replace on an as-needed basis. If I lived close to my boat and could work on this over the winter, then I might make a upgrade project and replace or re-work all of the valves.
The pictures below show the original galley hose and thru-hull and my new installation-
The Apollo valve is original - just cleaned-up and freed-up. The new 90 degree ell and the Groco adapter are bronze. The three bolts are bronze. They mounted the Groco adapter to the hull. Everything bedded properly of course.
Apollo makes bronze valves, maybe yours is bronze? Did you consider trying to disassemble it, to figure out why it was so hard to operate?
I've found new ball valves hard to operate, and the ones in my new boat are stiff. Other than soaking in PB Blaster, any ideas on lubrication for these?
I've found new ball valves hard to operate, and the ones in my new boat are stiff. Other than soaking in PB Blaster, any ideas on lubrication for these?
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I considered disassembly, but figured I would try PB Blaster first. I wish I had a magic potion, but alas I don't. I suppose I could remove the hoses from the valves and spray a liberal amount of PB into the top with the valve closed. But I also think it was beneficial to operate the valve every so often. Since I am 150 miles from my boat, this is not possible.
Maybe pouring some Marvel Mystery Oil down each sink and into each strainer might help? I have posted this question before now on this forum but have not received an answer that actually worked.
Yes the more you open close them the better they seem to be and if you open close them when you get to boat and close them keeps crud from getting into the values and than they get harder to open and close.
Newer design ball valves now come with grease fittings to keep the operating better.
https://www.groco.net/products/valves-seacocks/accessories/ulube-grease
https://www.groco.net/products/valves-seacocks/accessories/ulube-grease
I use wet vac every winter suck water out so it won't freeze and pour antifreeze and vegetable oil mix top of valve to sit for winter come spring they all open 1 finger
"Liquid MareLube™ is designed for valves where access is difficult or convenience is desired. Simply pour Liquid MareLube into the system through the valve tailpipe or hose, and activate the handle of the valve. This is a true Readily Biodegradable and biorenewable liquid lubricant developed for the regular maintenance of marine valves and seacocks. This valve service should be performed several times a season to reduce marine growth and keep seals lubricated."
http://www.iboats.com/16-OZ-Bottle-...vWrXRLroFp0sJd2wxaOHhavFFpP5DThBoCAwgQAvD_BwE
On my previous boat, with Marelon seacocks, I exercised them weekly, because I closed them all when leaving the boat, and opened them when I arrived. I never felt the need to lube them, in 17 years. They always worked perfectly, and easily.
I wouldn't leave a boat for a week without closing the seacocks.
The new one has ball valves. They are a bit tough to actuate, I think because the previous owners just left them all open. They are getting easier now that I've been actuating them regularly. I may lube them this winter. I'm thinking a fingertip or something with grease on it, on the outside. and pouring a small bit of liquid Marelube on the inside.
I plan on opening them all, to drain, once the boat is hauled, hence no antifreeze needed.
Don't haul every year. Head lube is just vegetable oil so what is marelube. Also Crisco good prop lube for those of us with folding props
What do you burn in the diesel engine, peanut oil? Sounds like a floating kitchen.
No the head lube they sell at wm is just a $5 quart of vegetable oil. But burning peanut oil would be cool and save me $25 a year on diesel.