Kohler canister flush valve drops too quickly

Discussion in 'Toilet Forum discussions' started by nostickers, Jan 29, 2012.

  1. nostickers

    nostickers New Member

    Messages:
    2
    Location:
    California
    I've had my K-3819 (1.6gpf with "Class Five" canister flush) for ~4 years.

    The tank is filling to the proper level and everything appears to work as intended. My only problem is that I have to hold the handle down for an extra second or so to make sure the toilet flushes fully, otherwise 75% of the time toilet paper reappears when the bowl fills. Is there any way to adjust how long the canister stays afloat before dropping? (other than the obvious... which is to hold the lever down a bit longer)

    [​IMG]
    Last edited by a moderator: Jun 8, 2012
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,313
    Location:
    New England
    One of several possibilities: there's a partial clog slowing the flow down the drain, the siphon jet is partially clogged, the rim jets are clogged (mineral deposits?), the tank to bowl path has something in it, slowing the flow; the bowl isn't getting refilled properly and part of the flush is filling the bowl - it must be full at the start of the flush (where is the refill tube?).

    All modern low flow toilets do not empty their tank when you flush but use that extra water to provide more pressure for the water that does go.
  3. SpaceFuzz

    SpaceFuzz New Member

    Messages:
    1
    Location:
    Seattle
    Same exact problem - incomplete flush on Kohler canister flush valve

    My Kohler K4632AA toilet has the same canister flush valve exhibiting the exact same symptoms as described by the OP.

    Essentially, if I push the lever and let go immediately, I only get a partial flush, since the canister raises and drops immediately. I have to hold the lever for a second or two (not very long) before the 3" tank opening (larger than the standard 2") allows the tank to completely empty (or nearly so). Only when I hold it does the bowl completely flush and make the "sucking air" sound that indicates a complete flush.

    There is nothing clogged or slow ANYWHERE, and the chain is not tangling as described elsewhere on this forum. It's just like what would happen if a standard flapper valve didn't have the captured air float and dropped immediately after tension was released on the pull chain. I'm baffled that Kohler thinks this is a good design, and have SCOURED the internet looking for adjustments, tweaks, or other fixes or workarounds. I'm about to resort to buying a replacement flapper valve that retrofits the 3" tank opening to a standard 2" flapper float valve as shown here (Keeney K835-10):


    Would love to find a fix for the canister as is, however. I just can't believe Kohler would endorse a faulty design. I keep telling myself, I MUST be doing something wrong...
    Last edited by a moderator: Dec 19, 2013
  4. Terry

    Terry Administrator Staff Member

    Messages:
    15,416
    Location:
    Bothell, Washington
    New toilets use 1.6 gallons or less. They are designed to only use a portion of the tank water.
    If you need or want more, you will have to hold the handle down longer. Even if you order a new flapper flush valve, that will be timed out to just drop 1.6 gallons. It's been that way since 1992, twenty years now.
  5. One time reply

    One time reply New Member

    Messages:
    1
    Location:
    Florida
    My experience is EXACTLY the same and I have seven of those toilets to deal with. One problem I found was that the holes under the rim are very small and can easily clog up. Another desperate compromise to get 1.6 gallons to do the job. Fuzzy pipe cleaners, some Lime Away, and a scrubby pad opened them up BUT, the problem went back to the canister itself.

    What actually WORKED was to zip-tie a tennis ball sized chunk of styrofoam to the canister. That adds buoyancy and now all toilets flush reliably. I wouldn't say it "cured" the problem but, the toilets are reliable now.
    Last edited by a moderator: Dec 19, 2013
  6. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,395
    Location:
    Yakima WA
    Here's a thought. Maybe this is one of the reasons many plumber stay away from Kohler toilets. My Totos don't require a hunk of styrofoam to work properly 100% of the time. I don't know, I just saying.
  7. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    If the water police catch you holding the handle down, there will be hell to pay!!!!!!!
  8. wjcandee

    wjcandee Wise One

    Messages:
    1,973
    Location:
    New York, NY
    Just because it doesn't empty the tank doesn't make it a "partial flush". Your issue is not that the thing opens and closes quickly: that's how it is supposed to work. As Terry explained, it's using the weight of the full tank of water to create water pressure to make the stuff go down with just a little bit of the water in the tank. You shouldn't need to hold the lever down longer except if you have extra material that needs extra water.

    I actually wanted to help address a different statement you made, to the effect that you can't believe Kohler would endorse a defective design. I would say, "Bwaahahahahahaha", but that might come across as rude, which I don't mean to be. That reaction comes from my own painful experience. I thought the same thing when we installed a very pretty Kohler toilet with the Ingenium flush, which Kohler is very proud of. The toilet was such a nightmare, requiring constant plunging, that I finally ripped it out and replaced it with a Toto Drake that I bought for a fraction of the price of the Kohler, and which works fabulously on just a sip of water. It, too, shuts the flush valve (a simple flapper design) almost as soon as it opens. The effect is jarring at first -- you can't believe it's supposed to work like that if you are used to old toilets -- but the stuff really does go right down. There's no mistaking that that's the proper function of that toilet. Not so with the Kohler. It just plain didn't properly flush solid matter, no matter how much additional water you gave it on the flush. The bowl started with the right amount of water and the toilet was level, two other potential issues that you should check, but the bottom line was that the functional design of this very attractive toilet sucked, and Kohler has to have known that it did. They plainly just didn't care -- and they still sell this piece of junk.

    I have to say that I was so happy with the decision to replace the toilet now having done it. It seemed like such a waste when I was contemplating it, which is why I took so long to do it. Now that it's done, I am so sorry I didn't do it sooner. Really, for the price of the professional help you will need to tweak one of your Kohlers to make it work as well as it can (which may not be so great in the end), you could buy and install a Drake yourself. And when you do and the thing works so amazingly-well, you will say, as I did, "Ahhhh. That's how the Kohler was supposed to function, but didn't." You will get, every time, that nice gurgle noise that you describe, and you will see that it can be done on 1.6 gallons and even on the 1.28 gallon EcoDrake, which often sells for basically the same price.

    PS I worry about that Keeney valve. It says it "fits" 3" toilets and even says it "is" a 3" valve, but you correctly point out that it looks in the photo like it's got a much-smaller hole under the flapper, quite possibly 2". I wonder if an expert could comment on this but it would seem to me that that would degrade the power of the flush, based on the simplest fluid dynamics. If you're trying to tweak your toilet, wouldn't you want something like a 3" toto flush valve, assuming that the refill tube can be had in the right height? Or maybe the Fluidmaster universal 3" flush valve (2.8" throat diameter). Don't know why they wouldn't fit if the Keeney does, but, again, I would want to hear what one of the experts says about the concept and those products. Of course, because we are not convinced that the valve itself is the problem here, you might just be spending money to end up with the same poor level of functionality.
    Last edited: Jun 9, 2012
  9. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,395
    Location:
    Yakima WA
    Kohler's poorly designed toilets have been cussed and discussed frequently on this forum. Many of us "mature individuals" grew up with Kohler toilets which were excellent products. Of course they used 5 to 7 gallons of water per flush, but they earned a reputation for quality. Sadly, with the advent of the low flow toilets some 20 years ago, they have done next to nothing about redesigning the trap way, but have spent gobs of money trying to make the old designs work with numerous changes in the flushing mechanisms. They are still relying on their previous good reputation to sell their toilets. Not all Kohler products are bad, but they cling to the old toilet designs.
  10. lchaverri

    lchaverri New Member

    Messages:
    1
    Location:
    California
    Same problem!

    I have the exact same problem and this is new. The toilet still uses the same amount of water if the handle is held up and it has nothing to do with the water fill line. It just seems like the canister does not stay up long enough to allow the one gallon of water to come through. The toilet is only a couple of years old, I really don't want to replace it. You would have thought with a brand like Kohler they would have come up with a better, long lasting design!



    Last edited by a moderator: Dec 19, 2013
  11. Gary Swart

    Gary Swart In the Trades

    Messages:
    7,395
    Location:
    Yakima WA
    The old "famous name brands" have been living on their past reputation since the low flow mandate came in to being. Yeah, you'd think they would be on the cutting edge, but rather than designing a better toilet, they have tried to tweak their old designs to make the grade. There have been some improvements to be sure, but there are still poor performing toilets among the famous brands. This is why Toto has become the world's largest manufacturer of toilets without resorting to dumping blems and seconds into discount stores and without extensive and expensive advertising.
  12. shortimer

    shortimer New Member

    Messages:
    1
    Location:
    Reno, NV, USA
    Kohler Flush Valve Drops too Quickly

    I have also had the problem of the inadequate flushing with my Kohler 4632aa toilet. This toilet has been in service about 3 years but lime build up in our area is minimal based on my experience living here for 18 years so any plugging of the water rim holes is not a problem. With the normal flush procedure (push handle down and release immediately) the toilet bowl often leaves material behind. In addition, any toilet paper above the toilet bowl water level often stays in place. I have called Kohler customer service and essentially was told there is no fix for this issue and low flow toilets work that way. Of course that is not true since I also have a Pegasis Low Flow that never has this problem. Not being satisfied with Kohlers explanation, I decided to see if I was getting the full 1.28 gal per flush. I made a pencil mark at the high water line when the tank was full and then shut off the supply line. I used the standard flush procedure and then marked the level in the tank when the flush was done and flush valve was down and closed. I have a very accurate 1 gallon container which I filled to the 1 gal. mark and emptied it in to the Toilet tank. Before I emptied the entire gal. the water level in the tank was already at the upper fill level that I had marked. From that info I determined that the tank is only using about 120 oz of water. This is roughly 90% of a gal. I think that the tank valve is closing much too quickly and there is not enough water coming out of the tank to get a decent flush. Since I just completed this test, I am calling Kohler tomorrow to explain the problem and the test I did to see if they have a solution to this problem. I will report my results here after I have spoken to their customer service agent.
  13. Terry

    Terry Administrator Staff Member

    Messages:
    15,416
    Location:
    Bothell, Washington
    And did you measure the water from the tubing that was refilling the bowl during the refill process?
    That water bypasses the tank and goes right to the bowl.
    If you turned off the water at the wall, then you are only doing a portion of the refill.

    [​IMG]
  14. jd944

    jd944 New Member

    Messages:
    2
    Location:
    Palm Harbor, Florida
    Somewhere around three years ago I installed two Kohler K-4632-AA toilets in our villa. Both of them flushed completely with a single, quick push of the lever. Aside from doing a poor job of washing the bowl, they worked reasonably well. Now, some three years later, both of them require holding down the lever for a complete flush. I checked the chains and both were correct. I spent 25 plus years as a building engineer in NYC and my experience tells me that the single flush models are not supposed to work that way. They are supposed to flush completely and properly with a single push of the lever using 1.6 liters of water. We have a whole house filter/softening system. Calcium and scale is not a problem. In my opinion, Kohler totally dropped the ball on this and put a poorly designed product on the market. I'll be changing both of my toilets over to the old fashioned flapper flush valves. Do they use more water, maybe. Do they require more maintenance? Probably. Do they flat out work? Definitely.
    Last edited: Dec 17, 2013
  15. Reach4

    Reach4 Well-Known Member

    Messages:
    2,796
    Location:
    IL
    huge.jpg

    If your fill valve looks like this,

    says it is adjustable. I don't know if you turn a nut at the top of the vertical rod, do something at the bottom of the rod, or rotate+raise the whole assembly, or if you need to change the fill valve to an adjustable version.
    Last edited by a moderator: Dec 19, 2013
  16. wjcandee

    wjcandee Wise One

    Messages:
    1,973
    Location:
    New York, NY
    Good luck with that. The Kohler canister flush uses a unique size hole in the porcelain, and so isn't easily replaced with an aftermarket flush valve. If you had an American Standard toilet with a tower flush or funnel flush, or a Toto or any number of other brands with a 3" flush valve, you could swap it for the Korky Large 3" Adjustable Flush Valve Kit, model number 5030BP. 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: Dec 17, 2013
  17. jd944

    jd944 New Member

    Messages:
    2
    Location:
    Palm Harbor, Florida
    I'm very much aware of the unique design of these units. If they can't be retrofit, I'll replace the toilets. I bought them to save water and now they're wasting water. Before I give up I'll check with a few large suppliers like Sexauer or Grainger. Like I said before, when they were new, they flushed perfectly with one flip of the lever. Not so three years later. I'm sorry but I can't subscribe to the opinion that they are working like they are supposed to. I'm not trying to be argumentative but I believe in calling it as I see it. There are a lot of people complaining about the same issue on these toilets. I find it hard to believe they're all guilty of operator error.
  18. wjcandee

    wjcandee Wise One

    Messages:
    1,973
    Location:
    New York, NY
    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.
  19. TM8

    TM8 New Member

    Messages:
    2
    Location:
    NY
    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!!!!
  20. wjcandee

    wjcandee Wise One

    Messages:
    1,973
    Location:
    New York, NY
    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.
Similar Threads: Kohler canister
Forum Title Date
Toilet Forum discussions Replace Kohler canister type flush valve Aug 13, 2014
Toilet Forum discussions White filler tube keeps popping off Kohler canister valve Jan 30, 2014
Toilet Forum discussions Kohler canister flush valve question Sep 1, 2013
Toilet Forum discussions Kohler toilet canister valve not staying up Dec 22, 2010
Toilet Forum discussions Kohler Wellworth Canister Flush Valve chain tangling? Aug 7, 2009

Share This Page