Replacement for galley through hull gate valve

[Steve]

I have an '84 Hunter 31 (great boat!). What I thought was going to be a relatively easy job (replace galley faucet), has grown legs!! The through hull gate valve cracked when I opened it back up. I have read the old forum articles and realize that it should be replaced with a ball valve. QUESTION: Can anyone suggest a good replacement (brand or mfg) for the 1 1/4 inch valve? Also, the existing gate valve is an in-line valve threaded onto a substantial extension of the through hull (about 2 inch extension). This would seem to prevent the use of a flanged seacock, yet everything I have read says to use such flanged seacocks and not in-line ball valves (because of the tapered vs. straight thread issue) Am I missing something? Any help would be greatly appreciated!!Thanks.

 

[Debra B]

replace the through hull

This has been in the water since 84, and is probably worth replacing. They aren't very expensive - and in fact it can be easier to cut the gate valve away from the through-hull than to take them apart.Your on fresh water, so disassembly might be easier, for for an additional expenditure, you won't have to worry about that item for LONG time.

 

[S. Sauer]

Seacocks vs Ball Valves

Since you are on an inland lake I doubt that you've experienced any substantial corrosion of a bronze thru-hull,but check it out for any signs of electrolysis before deciding to replace it. If it's solid and the bronze shows no pitting or a teltale pink color you might just keep it in place and using a penetrating oil/ solvent like PB Blaster or WD40, spray the gate valve / thru-hull threads.I would use only bronze ball valve with stainless ball (not Marlon). I believe the manufacturer was Apollo and I have read West MArine's disclaimer. I had no problem threading a 1-1/4" NPT valve sufficiently onto a straight thru-hull, and the sink and head discharge installations are now over 10 years old.Assuming you're out of the water you won't need to worry about incomming water. If not you could use a wood plug in from the outside of the thru-hull, or heel the boat at the dock untill the opening is out of the water using a halyard brideled to a midpoint of the mast and fastened to a piling further away.While holding the thru-hull's collar nut with a large pipe wrench or aircraft pliers, back off the gate valve. Clean the threads test fit the Ball valve. You will typically have straight thread on the thru-hull, however the ball valve should thread at least 3/4" onto it. Then apply a small bead of non-hardening sealant to the threads and hand tighten down the ball valve , making sure the thru hull isn't rotating. Continue to tighten the ball valve onto the thru-hull threads untill well seated and tight. Don't go so far as to bind up the ball itself, which can happen with marlon fittings.If you elect to install a bronze seacock it will be more labor intensive. You will have to do it with the boat out of the water and with the thru hull backed out. Again you would need to insure that the thread types are compatible and possibly get a new thru-hull with shorter threads. You also need a special internal wrench to tighten the thru hull into the seacock after applying appropriate thread sealant and bedding sealant. 1-1/4" thru-hulls and 1-1/4" ball valves should last forever in a fresh water sink drain application.

 

[Jeff]

Taper

It is common practice around my marina to slighhtly file the first few threads of the thru hull into a taper. This allows the ball valve to thread on to the thru hull deeper. It is best to put the thru hull into a vice and thread the ball valve on a few times before doing it on your boat. Of course you need to assume all risk since this method is against the standard recommendation.

 

[Steve]

Thanks.

Thanks for the help. I'll give it a try!