Installing Shut Off Valve on Back of Toilet

I have a Thetford Style II toilet in my 2011 Navion iQ. It has become very difficult to get the water to stop running. I bought a repair kit and did some searching and it seems the recommendation is to install a shutoff valve in case this ever happens again. The problem is, I'm having difficulty finding the same tubing, and fittings for it. The tubing is 5/8" OD, and 1/2" ID, but it's two layer. There's a white inner layer, and a vinyl outer layer with braided reinforcing.

Does anyone know if there's an easy way to do this, and where I could find the parts?

Thanks in advance.

you may have an easier time to install a valve at a connection as opposed to cutting the line to install a valve, the connections should all be standard- perhaps replace the thetford with a more reliable unit

NYBobbo said:

you may have an easier time to install a valve at a connection as opposed to cutting the line to install a valve, the connections should all be standard- perhaps replace the thetford with a more reliable unit

Click to expand...

I agree, sadly the connection is wedged into place by the hole that comes up through the floor. You can't remove the connection without removing the toilet. Kind of nuts, but it looks nice. I was going to setup PEX, elbows, and a valve, but the total cost was over $70 and it would have spoiled the look, so I've given up.

yes to do anything on these you need to remove them, not really any worse than a home unit. You can enlarge the supply line hole with a small saw or hole saw to go through the thin wood (at least on mine)