Help How cap off unused seacocks ?

[Cheechako]

Originally Posted by Terra Nova

Ball and gate valves have pipe threads which imperfectly mate with a thru-hull fitting's straight threads. and they have no provision for bolting.

Yes, you can only get a couple threads of engagement often.

[mitiempo]

Originally Posted by Cheechako

Yes, you can only get a couple threads of engagement often.

Groco tapers the NPS thread on their bronze through hulls so they will turn into a npt ball valve quite a ways - 7 or 8 threads.

[mitiempo]

Originally Posted by zboss

Why is one preferable to another?

Separate valves are easy to replace if needed. We could even replace them in the water if we blocked the through hull from the outside.

Groco has a great solution with their flanged adaptors. They have NPS threads for the through hull and NPT threads for the ball valve.

[Cheechako]

Originally Posted by mitiempo

Groco tapers the NPS thread on their bronze through hulls so they will turn into a npt ball valve quite a ways - 7 or 8 threads.

Not sure I understand how that works... they make them small diamter deliberately? Most often you cant get that many threads engaged on a mating pipe thread pair.

[mitiempo]

Originally Posted by Cheechako

Not sure I understand how that works... they make them small diamter deliberately? Most often you cant get that many threads engaged on a mating pipe thread pair.

Like all through hulls the Groco's have straight (NPS) threads. The last half dozen or so are slightly smaller so they will go into a ball valve (NPT tapered threads) quite a ways - somewhat over 1/2".

Go to a marine store that stocks them and try out the fit.

[jkindredpdx]

Originally Posted by arch007

Thanks for all the replies.

Wanted to leave it as is so can restore normal toilet if I remove the composting toilet.

arch

I used an expanding neoprene plug purchased from the hardware store. I replaced bolt, nut, and washer with high quality stainless.

[barnakiel]

I filled the thruhull externally with foam and epoxy and I closed the valve internally.

I like the idea of the cap. I see them in shops but could not get one where we hauled out.

Cheers,
b.

[Terra Nova]

Originally Posted by jkindredpdx

I used an expanding neoprene plug purchased from the hardware store...

Good luck.

[model 10]

Originally Posted by Terra Nova

Good luck.

If you will notice, that is a bung type seacock. Short of the whole thing breaking off, he needs little luck.

[jkindredpdx]

Originally Posted by Guy

If you will notice, that is a bung type seacock. Short of the whole thing breaking off, he needs little luck.

I admit Terra is partially correct... Left unattended it could be disasterous. However, the seacock is closed, I sucked out water from the seacock, and twice a year when maintaining my seacocks I remove and inspect the plug to ensure there is no corrosion. Too early to tell, it's only been in since I installed my composting toilet in 2013.