What Not to Do When 20+ Year Old Thetford Toilet Starts Having Issues
Posted: Mon Dec 16, 2019 8:25 pm
The toilet in my 1992 Bounder 31K encountered a couple of issues over the last two years. The first issue popped up May of 2017 years ago when the water valve started leaking. Ordered a new valve online for about $20, removed the toilet (really easy to do once you know the secret handshake, so to speak), and installed it.
Whoops, forget to order the neoprene gasket to remount the toilet. Ordered the gasket for another $10 (including shipping). I could have ordered a water valve with the gasket for $22.
Fast forward 6 months later. The water in the bowl started leaking past the flush “swiper” blade. I squirted some silicone spray on it and seemed to have fixed the problem for about 6 more months but started leaking past the swiper blade again. I was going to buy the rebuild kit for the flush valve for $30, which seemed like a much better deal than buying a whole new mechanism for $101. However after reading the reviews on the rebuild kit, there were a lot of comments that the kit did not fix the leak. The issue was the state of the swiper blade itself. They tend to build up mineral deposits and scratches over the years. I decided to spend the extra $70 to get a whole new mechanism, which also was going to save me at least 2 additional hours of installation work versus the rebuild kit.
That was one of my better decisions in life
. After installing the new mechanism, which was absolutely effortless (well, maybe small amount of effort), I inspected the old mechanism. I don’t think the old one would have held water with just a seal kit, based on the condition of the swiper blade.
The key takeaway from this is that if you’ve got a 20+ year old Thetford RV toilet with even just a leaky water valve, you’re probably best off replacing the whole mechanism. If one seal is failing, the others are probably going to start failing in the near future as well.
Whoops, forget to order the neoprene gasket to remount the toilet. Ordered the gasket for another $10 (including shipping). I could have ordered a water valve with the gasket for $22.
Fast forward 6 months later. The water in the bowl started leaking past the flush “swiper” blade. I squirted some silicone spray on it and seemed to have fixed the problem for about 6 more months but started leaking past the swiper blade again. I was going to buy the rebuild kit for the flush valve for $30, which seemed like a much better deal than buying a whole new mechanism for $101. However after reading the reviews on the rebuild kit, there were a lot of comments that the kit did not fix the leak. The issue was the state of the swiper blade itself. They tend to build up mineral deposits and scratches over the years. I decided to spend the extra $70 to get a whole new mechanism, which also was going to save me at least 2 additional hours of installation work versus the rebuild kit.
That was one of my better decisions in life

The key takeaway from this is that if you’ve got a 20+ year old Thetford RV toilet with even just a leaky water valve, you’re probably best off replacing the whole mechanism. If one seal is failing, the others are probably going to start failing in the near future as well.