I just replaced the insides of a toilet with a fluidmaster 404 complete set and now it will not flush correctly. The flapper closes before the tank is half empty. I've double checked the instructions and have done everything listed. There is an adjustment on the flapper that controls the amount of water entering the bowl. I'm assuming that when it is set at maximum the flapper is supposed to stay open longer. If it does adjust the time the flapper is open it is very slight and I can't see any difference. Any ideas what I can do other than pulling this all out again? I've spent the whole afternoon messing with this and nothing works. And I'm really not looking foreword to pulling this apart again.
Thanks for any help, Linda

The flapper has numbers that that indicate a longer or shorter flush. If you have a modern toilet try setting the flapper to number 4, for stronger flushing or an older toilet try a higher setting.
For more information you can call Fluidmaster Tech Support at 800-631-2011 ask for Mike at ext. 2232