Plumbing questions

[Dean Abramson]

I want to add an in-line Groco ball valve (https://www.westmarine.com/buy/groco--f ... ecordNum=1) to the flush-water intake line of our toilet.

I am tired of having to go inside the vanity cabinet to open the seacock. And I don't trust the toilet's valve.

As it now is, the hose has only fairly gentle bends between the seacock and the toilet. But with my physical space requirements, once I add the valve, having a 90 degree fitting (https://www.defender.com/product.jsp?na ... id=2628255) right after the valve might be necessary. So, my first question is this: would having that 90-degree bend in any way negatively effect the flow? Make it harder to pump?

Also this: I notice that the elbow for use with 3/4" ID hose has a 1/2" NPT thread. It would seem to a plumbing dummy (like me) that the 1/2" threaded part would be a constricting point in a 3/4" ID hose. No?

[Frenchy]

A 1/2" NPT thread has an OD of about 27/32", so it is not constricting. As for adding the ball valve, my preference is
to leave everything original. You could possibly leave an alert posted on the wall to close the seacock when leaving. -Jean

[Jim Walsh]

Reaching into the vanity to shut the head intake seacock ensures no water can enter the hull. Leaving that seacock open and adding an in-line ball valve for convenience will leave the vessel at risk for sinking. Big decision, more so than it appears at first glance.
Perhaps I've misinterpreted your posting.

[Dean Abramson]

Thanks, Jim

Well, we are not contemplating leaving that seacock open while not on the boat.

But we would like to be able to have a more accessible valve for each individual head use. I envisioned leaving the seacock open while we are aboard, and using the ball valve on a per-use basis. I guess I figured that the combination of the ball valve and the (marginal) toilet valve would be safe enough. And I know someone who operates this way; but maybe his valve is different. ??

Also, I think that non-boating visitors would be able to learn the ball-valve routine better than the seacock routine, because where I am planning to locate the ball valve will be very obvious.

Are those ball-valves really that unreliable?

[Jim Walsh]

Thanks, Jim

Well, we are not contemplating leaving that seacock open while not on the boat.

But we would like to be able to have a more accessible valve for each individual head use. I envisioned leaving the seacock open while we are aboard, and using the ball valve on a per-use basis. I guess I figured that the combination of the ball valve and the (marginal) toilet valve would be safe enough. And I know someone who operates this way; but maybe his valve is different. ??

Also, I think that non-boating visitors would be able to learn the ball-valve routine better than the seacock routine, because where I am planning to locate the ball valve will be very obvious.

Are those ball-valves really that unreliable?

That modification would serve your purpose while maintaining the integrity of the hull with the existing Spartan seacock.

[Bill Goldsmith]

Here is what I did. I drilled a little hole at the end of the seacock handle and connected two thin lines with pulleys and padeyes that go through the cabinet. Pull one to open the seacock, pull the other to close. Works great! I put a green ball on the open and red ball on the "close" handle. No opening the cabinet, no reaching around to find the seacock. And guests figure it out very quickly.

[Dean Abramson]

Wow! That's impressive!