Rubber toilet parts degrade in water. No surprise there, but there are two ways for the rubber that is used in plumbing to be exposed to water.
I've been a plumber in the Portland area for many years, and I am a person who pays attention to details. Let me teach you somethings about rubber toilet parts that I've learned by observation.
Many of the rubber seals and gaskets in fixtures and drains are only exposed to water at their leading faces, because they're intended to hold water back at that face. We call these compression seals, or compression gaskets.
Rubber gaskets that are compressed into place and exposed to water only on one face can take decades to rot to the point of letting water pass them, especially if they are not moving parts.
Rubber parts that are submerged on all sides on the other hand can rot and distort to the point of uselessness in less than a year. Both ways of using rubber can be found in toilets.
The gaskets that seal the fill valve, and the flush valve where they are affixed to the china tank are compression gaskets. The inner rubber parts in fill valves are submerged. The rubber seals that are found in flush valves, whether they be flappers, flush balls, disks, or some kind of ring gasket are submerged.
The two factors that affect the rate at which submerged rubber degrades are-
Remember, just because it is rubbery doesn’t make it rubber. You are also going to find neoprene, and plasticized rubber in plumbing parts. We're talking about rubber.
Engineers use different materials to get various performance characteristics. Most flappers and flush balls however are rubber. Most of the seals in fill valves are rubber.
Here's where the (toilet tank) rubber meets the road. Those thin, supple rubber flappers and seals that work so well don’t last worth a darn when submerged.
You should use good high quality supple rubber toilet parts when you do it yourself. Why? Because they are inexpensive and easy to apply. Keep a spare on hand and change it once a year or as needed.
I tried some of the longer life flappers to give my clients a better product and this is what I found. If the parts were perfectly shaped and stored flat they were OK. If not, they leaked the first day. They're tough but not supple. I went right back to the thin supple rubber I've always used.Plumbing Supplies from Rubber Toilet Parts