Flapper Flop

Discussion in 'Toilet Forum discussions' started by Kiko, Aug 14, 2013.

  1. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    I've got a Kohler K4620 two-piece toilet.

    When the flapper started leaking, I replaced it with a Korky red "universal" flapper. This flapper didn't seal properly, so I went to the plumbing supply store for the OEM flapper. They could not find my model number on their computer and finally sold me a GP85160, which seems to be Kohler's "universal" flapper. They said that the float was pre-adjusted for 1.6 gal toilets.

    Nope! The flapper closed in 1/2 a second at that setting, so the flush was useless. I moved the float all the way down on the chain, and it is better, but still closes too soon. I'm wondering if I should have gotten a GP87449 (same flapper w/o float). It sure seems like it would be a lot easier to install and give me a better flush.
  2. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
  3. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,835
    Location:
    Cave Creek, Arizona
    I usually install the conventional flapper in the Wellworth toilet then adjust the water level to give the desired flush time.
  4. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    Terry, now I know why that (K4620) number wasn't in their computer. It was for the tank, which is discontinued. They still should have been able to cross-reference it though you would think, instead of having me look through a hundred toilet diagrams to try to pick out my toilet.

    I like HJ's idea of using the floatless flapper and adjusting the water level.
  5. Terry

    Terry Administrator Staff Member

    Messages:
    15,130
    Location:
    Bothell, Washington
    A nother solution would be to pick up a Fluidmater flapper that lets you dial it down to 1.6 gallons, or a standard 1.6 gallon flapper that drops quicker.
    The higher the water in the tank, the better the flush.
    That's why the old lo-boy one piece toilets had such a hard time flushing.
  6. wjcandee

    wjcandee Wise One

    Messages:
    1,898
    Location:
    New York, NY
    Okay...

    The part should have been in their computer because the part (flapper) is for the tank.

    In fact, if you look at Terry's link, there's a link to "service parts". The specific flapper that came in your toilet is long discontinued/supplanted. The correct part, according to Kohler, for you to use in your toilet is the very part that your supplier sold you, the GP85160. (Links below.)

    http://www.us.kohler.com/us/catalog/partProductDetails.jsp?partNumber=1006958

    http://www.us.kohler.com/us/catalog/partProductDetails.jsp?productId=637980&substituteskuId=613426

    HJ's "solution" is creative, but of course this means putting in a flapper that drains the tank and adjusting the water level downwards, which results in a less-powerful rush of water out of the tank. What I see everywhere, of course, is that plumbers install the "drain the tank" flapper, then allow the tank to be filled to 1/2" below the top of the overflow riser, which turns the thing back into a 3.5 gallon-per-flush toilet. This illustrates how easy it is to defeat the water-saving features of low-flow toilets. The sad part is that the 3.5 gallons running through that toilet doesn't produce anywhere near as effective a flush as a modern 1.28gpf Toto.

    If you aren't satisfied with the flush on that early low-flow, at some point you might invest in a more modern toilet with a 3" flush valve that actually accomplishes something with 1.6 or even 1.28 gallons per flush. Even a basic Toto Drake at around $200-ish would probably surprise you. If that's out of your price range, even something like a Delta toilet would give you a decent flush.

    PS Korky also makes a number of "dialable" 2-inch flappers. This one is the newest: http://korky.com/Flapper100BP.html This one is one I have used and gives decent if not pinpoint control: http://korky.com/PDF/16BP.pdf This one is probably closest to your Kohler flapper -- no dial but it adjusts with the float thingy: http://korky.com/Flapper2004BP.html

    Also, if the flapper is closing too fast, make sure the "wings" are positioned correctly on your flush valve hooks. It doesn't always solve the problem, but sometimes helps.

    Good luck!!
    Last edited: Aug 15, 2013
  7. Kiko

    Kiko New Member

    Messages:
    175
    Location:
    Royal Oak, Michigan
    My chief concern is that the flapper seats properly, which the GP85160 does so far.
    I've moved the float down a bit further and the flapper stays open enough now.

    BTW, my brother has three Toto Drakes and is always complaining about the quick flush.
    He was asking me how I could get those 3" flappers to stay open longer.
  8. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,360
    Location:
    Yakima WA
    Complaining about a Toto Drake's quick flush is like complaining about a Porche's quick acceleration. That quick flush is what make the excellent performance possible with a minimum amount of water.
  9. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,835
    Location:
    Cave Creek, Arizona
    quote; which results in a less-powerful rush of water out of the tank

    The difference in the water level is usually about 3-4 inches which translates to about 2 to 3 ounces psi, which is usually not enough to cause any difference in the flush. The low boy toilets used the tank water for the siphonic action and the "bypass" valve to wash the rim.
  10. wjcandee

    wjcandee Wise One

    Messages:
    1,898
    Location:
    New York, NY
    Huh. As an experiment, I filled my GMax Toto about half way up, then flushed it by holding the flapper open and evacuating all the water from the tank.

    Noticeable difference in flush power. Is that odd?

    Frankly, if it doesn't make any difference, the why did manufacturers bother setting them up this way?
  11. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,153
    Location:
    New England
    A little extra height never hurt, plus, by not evacuating the tank, you have some (likely) room-temp water to temper the incoming cold from the supply which can minimize tank sweating.

    FWIW, one of the big deals about flushing fast is that, to do it, you must push most of the water out in a very fast manner - this clears the bowl better. It also means it refills faster, since it didn't use much water.

    As long as the toilet does its job, what's the deal about it being quick about it?! It would be another thing if it left stuff behind, but that's rarely the case with a Toto and an open drain (i.e., no clogs).
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