On Kohler toilets and some American Standard toilets, you will see a tower style flush valve. Tower style flush valves have a round rubber gasket to keep water in the tank instead of a flapper. The tower flush valve seal can and will go bad eventually just like any other toilet flapper. A flush valve seal will usually go bad and begin to leak due to age, hard water, tank chemicals, being allowed to dry out (no water usage), or a combination of any of these.
Other times a seal will bend in at the bottom preventing a good seal and resulting in a running toilet.
The good thing is that a tower flush valve seal is at least as easy to change as a normal flapper. It is just a little different. Here is an example of what you might see with this type of valve and how to change the flush valve seal on tower type toilets.
- Shut off the water to the toilet. Who wants to work with running water spraying all over the place especially after you disconnect the fill tube. Turn the shut-off valve under the toilet to the off position. Flush the toilet and check that it doesn’t refill. Then hold down the handle to empty as much water from the tank as possible.
- Remove the fill tube that goes into the overflow. Some tower toilets do not have this but the Kohler toilets do. The fill tube needs to be removed before you can get the seal off of the tower. To do so just pull the fill tube out of its housing or remove the clip if it has one and then pull the tube out.
- Remove the old flush valve seal. Take hold of the sides of the rubber seal and pull it out of the groove that it sits in. Work the valve seal up and out of the groove all the way around the tower. Keep the seal moving up the tower a little at a time until it is all the way off.
- Install the new flush valve seal. Position the new valve seal onto the top of the tower and slowly slide it down toward the seal groove at the bottom. Pull one side of the seal into the groove and hold it in place with one hand while working the rest of the sides into place until it fits evenly on the tower all the way around. Check that the seal is completely in the groove.
- Reinstall the fill tube. Connect the fill tube back into the tower the same as it was before. If you didn’t need to remove a clip the fill tube just pushes back snugly into its hole. Otherwise, position the clip the same as it was before.
- Turn the water supply back on. Wait for the toilet tank to fill completely then check that the toilet flushes correctly. Make sure that the new flush valve seal sits snugly on the tank opening. You can often hear if the seal is leaking which occurs if the flush valve seal is not positioned evenly in the groove all the way around the tower. Flush the toilet several times and watch for any problems before putting the tank top back on.
Note: Another reason to change the seal is when it becomes hard to flush the toilet. An old stiff flush valve seal can put extra stress on the handle or chain. If you notice that the toilet is getting harder to flush it may be beneficial to change the flush valve seal before something breaks.