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?
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?