American Standard Champion 4 Replacement Flush Valve for Two Piece Toilets by NuFlush

The issue we had with the OEM Champion 4 flush valve was that it leaked CONTINUOUSLY. Over a 5 year period we changed the flapper seal 3 or 4 times. It never sealed for any length of time. The first time, yes, the seal had "bubbles" in it, so we thought problem was solved. It wasn't. Other seals had no apparent defects, and still leaked from day 1. I suspect the flapper, which moves "straight up-and-down" (not on a hinge) did not come down straight, to cover the whole sealing surface. Just take the tank lid off and move the flapper with your finger, and the leak stops. Don't want to take the tank lid off and move the flapper with a finger every time we flush. Installed the NuFlush, which has a 3 ½ inch flapper on a hinge. Problem SOLVED. Yes, it does flush noticeably stronger than the Champion 4 did (NuFlush emphasize this feature), but lack of flush strength was not the issue we were addressing. No surprises nor difficulties with the install. TIPS : (a) To remove and replace the 4" plastic flush valve nut - use one of those motor car oil filter wrenches with 3 fingers (thank you to someone elses' review I read prior to purchase). (b). Order the kit that comes with 2 spare flapper seals. I did not, realize the option existed, and have ordered extra seals separately in hindsight