Toto Drake leaking into bowl

Discussion in 'Toilet Forum discussions' started by mike7, Dec 10, 2009.

  1. mike7

    mike7 New Member

    Messages:
    4
    Location:
    Seattle
    I have a 2-year old Toto Drake (C744S) that's had a persistent problem with leaking into the bowl. I've noticed there are several threads here on similar problems, but after reading all of them I'm still at a loss on how to fix it.

    The problem is a very slow leak, I *think* through the flapper. It's intermittent. My guess is that the flapper makes an incomplete seal after some flushes and seals properly after others, because the leaking happens maybe 1 flush out of 4. That is, if I flush and come back to the toilet, say, 20 minutes later, 3 times out of 4 the water level will be exactly at the fill line. The other 1/4 of the time it'll have leaked down about 1" below the fill line over 20-30 minutes. It's such a slow leak that it never even quite trips the fill valve; it'll just sit there at the 1"-down level with the fill valve open just enough to keep the water level constant at that point.

    I thought I had this problem fixed about a year ago. After the plumber who installed it gave up on fixing it, I read everything I could find on it and tried a bunch of solutions. I replaced the flapper with a new one, sanded the nylon ring that the flapper falls onto to form its seal because there was a little roughness, cleaned everything thoroughly... nothing helped. What finally seemed to fix it was adjusting the chain length between the flapper and trip lever. The plumber had installed it really tight, with a bunch of slack links hanging over. I loosened it up by a couple of links and removed the extra links. That seemed to improve matters, and with a little experimentation I found a length that seemed to make it work reliably.

    It had been working fine for a year, but over the past couple of months it's back to its old tricks. 1/4 flushes it'll leak slowly. I've gone back and cleaned everything and checked the chain length, but I can't seem to get it working again.

    Any ideas? I've seen "silicone spray" mentioned here several times for this kind of problem, to spray on the flapper, but I don't know quite what that's referring to - is that just WD40, or something else?

    Also, is there anything other than the flapper that could be leaking? It seems pretty clear that it is the flapper because of the way it leaks after some flushes but not others (the obvious thing that changes between flushes is the way the flapper is seated), but is there something else I'm missing that I should be checking?
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,817
    Location:
    New England
    Is the overflow hose attached with the provided clip, or stuck down the overflow tube? If it is stuck down the tube, attach it to the clip! or fabricate something to position it above the overflow and see if that makes any difference.
  3. mike7

    mike7 New Member

    Messages:
    4
    Location:
    Seattle
    Yes, the hose is properly clipped to the tube.

    I'm pretty sure it's not a siphoning issue, if that's what you're getting at. The toilet fills after each flush exactly to the fill line marked on the overflow tube (about half an inch below the top of the tube) - there's no water running over the top of the tube or anything like that, and I don't see any water coming out of the hose after the tank has refilled after a flush. The level of water in the tank just s-l-o-w-l-y drops over time.
  4. krow

    krow Plumber

    Messages:
    906
    Location:
    Ontario, Canada
    Don't waste your time with sprays and greases .99% of the time, the symptoms that you are describing is your flapper. Replace your flapper and it should be as good as new
  5. mike7

    mike7 New Member

    Messages:
    4
    Location:
    Seattle
    Replacing the flapper was my first thought, too, and I've tried that - more than once.

    Here's the bizarre thing: I actually have 3 other of basically the same Toto toilet that all work fine. I've swapped flappers between them, and the others keep working and this one keeps leaking.

    So I'm pretty convinced it's not the flapper itself.
  6. Terry

    Terry Administrator Staff Member

    Messages:
    14,783
    Location:
    Bothell, Washington
    In fact, it will be new.
  7. Runs with bison

    Runs with bison New Member

    Messages:
    891
    Location:
    Midwest
    Have you tried calling Toto? I would ask for a new flush valve.

    Have you ever pulled the tank, checked the flush valve nut to make sure it is tight and even, that it doesn't have a damaged gasket, and that there are no surface irregulaties on the tank interfering with its tank to valve seal?

    You've already been able to rule out the flapper, the fill tube, and the chain. That leaves only the flush valve itself. Someone once mentioned an alignment issue with the overflow tube that was causing trouble.
    Last edited: Dec 14, 2009
  8. mike7

    mike7 New Member

    Messages:
    4
    Location:
    Seattle
    Thanks for the ideas. The flush valve sounds like the best bet for the next thing to try changing. Given that the problem is intermittent, it seems like it's got to be something that's perturbed on each flush, and the flush valve seems like the most likely thing after the flapper that fits that description.
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