www.korky.com That kit uses a nice Korky 3" flapper and a twist-to-adjust-the-height flush valve and overflow riser. But that item clearly states that it does not fit ANY Kohler toilets...
Last edited by wjcandee; 12-17-2013 at 12:00 PM.
I will just make my usual comment to the effect that if you want a workhorse toilet that does the job every time but is not outrageously expensive, check out the Toto Drake (it's the original model of Drake) CST744S (1.6gpf) or CST744E (1.28gpf). It should be available for about $200+ ish, not including a seat. Great toilet. Have two of them. Flushes very well. Decent if not exceptional bowl rinse. Well made. Uses standard, easily-replaceable parts, most of which are made in the USA by Korky and for which there are Korky replacement parts. There is also a CST744EN, which has a different (N for "new") tank which looks more traditional and less-modern.
The Toto Drake II, CST454CEFG, is an upgrade, with better bowl rinse, a Sanagloss stain-resistant finish, and Universal Height all standard. But we love our original Drakes, and think they are a best buy.
I know this post is old...but I wanted to reply with how I solved this problem in case it can help anyone else. After having the Fluidmaster valve replaced, I had the same problem. The canister would fall too fast and not enough water would go into the bowl to flush it. A plumber couldn't even figure out how to fix it and said I'd just have to hold the handle down for several seconds each time. Well with several young children in my house, they were never going to be able to get it to flush each time. I finally realized the Fluidmaster float needed to go up much higher to keep the water level higher in the tank. This keeps the canister "flapper" thing buoyant long enough for the proper amount of water to get into the bowl and flush it. I did have to remove the fine adjustment rod on the side of the Fluidmaster unit in order to be able to turn the unit 360 while pulling up to get it to rise (the adjustment rod would hit the back of the tank keeping me from turning the unit). It only went up an inch at first...which wasn't high enough to keep the canister buoyant long enough. After messing with it longer and pulling harder, it went up to the top of the tank. The water now fills to the very top of the canister (when it's seated all the way down), and this is high enough to keep it from dropping down too fast. I hope this helps someone who is as frustrated as I was!!!!
Of course, cranking up the water level to a point higher than it used to be is going to destroy part of the water-saving nature of the toilet.