I have an American Standard toilet that will not completely flush on the first flushing attempt but will then flush fine on the second flush. I’ve replaced all the tank fittings and the wax seal under the bowl. It is not a water-saver model. It has this problem since it was new. What can be the problem?
Is there a styrofoam float on the chain that connects the flapper? If so adjust the styrofoam so that it is closer to the flapper. If not try replacing the flapper. Good Luck, Bill The Local Plumber Tustin, California http://www.TheLocalPlumber.com