I just replaced all the parts inside my toilet. It flushed fine before I did this; the gaskets were worn out and needed replacing so I went ahead and replaced everything.
I need to increase the flush time. The flapper closes before the toilet is finished flushing. If I hold the handle down when I flush a few extra seconds it flushes fine.
Where should I start making adjustments?
You may have used the wrong flapper. Many toilets today use the flapper design to achieve the proper GPF. The so-called "universal" flappers often either flush too much or too little.
If you are unable to find an OEM flapper, then Fluidmaster and Korky make an adjustable flapper, where you can adjust the timing of the flush. You should find these at any box or hardware or plumbing store.
Originally Posted by Terry
I agree. My toilet flapper stopped sealing so I bought a universal one at the local hardware store, and was getting real upset that it was closing right after flushing. I eventually looked at the directions and figured out I needed to cut out a certain piece if I wasn't using it. Once I did that, my problem was gone.