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post #1 of 2 Old 11-16-2008 Thread Starter
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Thru-Hull and Seacock

Presently I have a 1/2" thru-hull fitting that terminates in a 1/2" gate valve. This feeds raw water cooling to the inlet of the water pump.

I would like to change the gate valve to a new seacock (a ball valve with an integral flange that bolts to the hull for added strength and safety). However, I am having trouble finding a seacock in 1/2" size. Most (perhaps all?) start at 3/4". Groco is an example.

Does anyone know where I can find a seacock (with flange) in 1/2"? I do not want to use a standard ball valve. Apparently there is a safety issue mating the NPS threads of the thru-hull to the NPT threads used in most ball valves.


C&C 29 Mark I
Port Credit, ON
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post #2 of 2 Old 11-16-2008
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You'll be best to up size the system to 3/4" anyway. 1/2" thru-hulls and valves can plug up quite easily. You can always reduce it back to 1/2" at the sea strainer.

-Maine Sail / CS-36T

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