Originally Posted by
letmetellu
It is possible thaat the problem is not the flapper at all.
I will explain another possibility if your commode is like I suspect:
You have an overflow that has a small plastic tube sticking down inside of it, this is to replace the water in the bowl to a propper level. This small tube should only be sticking down into the larger tube about 3/4 of an inch, this should be above the water level of the water in the tank when it is full. If the small tube sticks further into the bigger tube than the water level, it will set up a syphoning action each time it is flushed, the water level in the tank will fall, the float then will call for more water to refill the tank. If this is the problem it will occur over and over. Also if this is the problem I would like it if you told me about it.