Thetford Toilet Flush Valve

[C&G in FL]

On a thread entitled “Hello,” I recommended having a spare toilet flush valve in/with the trailer. Glad I had one because I needed it recently when a relatively small stream started flowing from underneath the toilet into the shower’s recessed floor. Because the flow stopped when the water was shut off, I knew it was the valve and not the flange seal (yuk). A replacement valve is $25 to $30. A bracket held on with two Phillips screws holds the rocker that opens and closes the valve mechanism in place. Investigation revealed that an O-ring on the shaft appeared to be slightly abraded. I matched the O-ring at an Ace Hardware, put some silicon plumbers grease on it, and reassembled it. Pressure testing it indicated that it doesn’t leak. While I would still recommend having a spare flush valve, if the original does start to leak, it can most likely be “rebuilt” with a 33 cent O-ring rather than paying $25 to $30 for another backup.