Toilet tank fills but slowly drains w/o refilling

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Zanne

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After replacing the broken rubber washers on my toilet tank, it wouldn't fill up (water would run but it was leaking out of various spots in the old fill valve) so we replaced the fill valve with some old Fluidmaster kit (Fluidmaster 404LG). It filled up just fine without leaking. No leaks anywhere, water in toilet bowl doesn't visibly move. I flushed the toilet once and it refilled. Later went back and went to flush again but the water had drained out. I checked the flapper and it seemed to be fine. If I tap the flush lever it triggers the fill valve to start filling the tank, but then over time the water drains out somewhere and it has to be refilled every time someone wants to flush. Not sure if it is a crappy fill valve or what. The center gasket between the toilet and tank looked in rough shape but we were waiting on the replacement to arrive. It has arrived now, but we haven't installed it yet. I don't know if that would make a difference. If it was a problem with the flapper, then the fill valve should just keep refilling when it loses water, but it doesn't.

Any idea what the problem is? Bad fill valve? Or maybe it needs adjustment?

Someone recommended Fluidmaster Performax for the Toto Drake toilet (which is what I have) but I'd like to hear some ideas on possible fixes before replacing the valve again.
 
It's either leaking from the bottom of the flapper (stick your finger and make sure there is no crud under the flapper or matching seat, or the little hose is sticking inside the flush tube, siphoning water out.
 
Hmm.. I'll check again to see if there's any obstruction to the flapper. The hose is hovering above the overflow tube on a clip thingy. Any thoughts on why the tank isn't refilling when it drains?

Thanks!

As a complete aside, do you still admin on the houserepairtalk forum?
 
Does it have a Fluidmaster Leak Sentry fill valve? That will prevent the tank from refilling if you have a leaky flapper.

 
Rickyman, I think so. It has that thing on the bottom with the chain going to the arm. I noticed that when I was holding the lever up to check for any crud under the flapper, the water stopped filling. I'm going to see if changing the flapper fixes the problem. I'm tempted to get the THU440-A flush tower instead of the flapper, but I'm not sure if it would fit properly with the current flush lever & fill valve. It looks like the metal arm from the flush lever might be too long, but I'd have to see. I think I might have a spare 3" flapper in the bathroom somewhere. I tend to hoard parts & tools.
I found a video of how to install the tower system and am waiting for it to load (internet is too slow right now).

Edit: Correction, I'd need to get the THU440.15H-A as the replacement.
 
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Zanne, I would just get a regular Fluidmaster 400 and you might have to replace your flapper if it won't hold
 
Buy a fluidmaster #242 disc that will fix the intermitant flushing
when yoh flush it wait till it fills shine a flashlite down the over flow tube it may be cracked and leaking
With the flush valve fixed it will keep refilling
 
I replaced the flapper with a spare one I had lying around. I have been able to flush without refilling the tank every time I've gone in there but I'm not sure if it is still leaking or not. If the current fill valve is stopping it from wasting water if there are leaks, then I'm fine with keeping it. I'll have to check out the overflow tube as suggested though. I'm also wondering if the gasket could be a source of the leak but I would think that would only be the case if the flapper wasn't working.

I still want to switch to the tower flushing mechanism eventually, but I'm waiting to hear back from Toto on how to order the THU440 .15H-A. I've only seen the faulty flush valve that it replaces for sale.

Thank you for all of the replies.
 
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I replaced the flapper with a spare one I had lying around. I have been able to flush without refilling the tank every time I've gone in there but I'm not sure if it is still leaking or not. If the current fill valve is stopping it from wasting water if there are leaks, then I'm fine with keeping it. I'll have to check out the overflow tube as suggested though. I'm also wondering if the gasket could be a source of the leak but I would think that would only be the case if the flapper wasn't working.

I still want to switch to the tower flushing mechanism eventually, but I'm waiting to hear back from Toto on how to order the THU440 .15H-A. I've only seen the faulty flush valve that it replaces for sale.
One last thought if it wasnt mentioned....have you dyed the tank??????????

Thank you for all of the replies.
 
Geofd, no. I haven't tried dying the tank. I'm afraid it will permanently stain the toilet knowing our luck. Even with the flapper changed out there still seems to be a slow leak. I adjusted the flapper on the chain so it would flush better and that helped a little, but not much when the tank is not full. I still need to find my flashlight and look down the overflow tube. Not sure if I'll be able to see anything as everything inside the tank has a black coating from all of the sediment in the tank.
 
That toilet sounds like a total POS, just change it out.

Every single thing on it is failing, stop throwing parts at it.

You can get a decent cheap toilet for $125.00.
 
Geofd, no. I haven't tried dying the tank. I'm afraid it will permanently stain the toilet knowing our luck. Even with the flapper changed out there still seems to be a slow leak. I adjusted the flapper on the chain so it would flush better and that helped a little, but not much when the tank is not full. I still need to find my flashlight and look down the overflow tube. Not sure if I'll be able to see anything as everything inside the tank has a black coating from all of the sediment in the tank.
home depot makes a dye just for this reason......
 
Jeff, it's actually a very good toilet, but my plumbing isn't ideal. The flange underneath the toilet is broken & we need to replace the flange. Still waiting for the plumber to call me back to schedule a day to come out-- there's only one that will come out here & he keeps busy so I keep getting his answering machine. The internal parts of the toilet are no longer used & Toto has brand new flush valves. I've been in contact with them to order the newest flush mechanism that comes with a new overflow tube. It might be covered under their warranty, but we'll see. The part costs about $20 which is cheaper than buying a new toilet. I looked for cracks in the overflow tube but couldn't see any. I adjusted the flapper so it is flushing much better now.
The flapper and fill valve I already had lying around so I didn't have to go out and buy them. It has cost me less than $10 in repairs so far.

Geof, I'll have to look for the dye next time I'm at the store. I'm honestly not sure how to adjust water level on the Fluidmaster thing. My friend set the height of the valve itself to match the height of the previous fill valve and it fills to just under the top of the overflow tube & does not go over. Next time the tank is empty I'm going to run my hand along the outside of the overflow tube to see if I can feel any cracks since I can't see any. I'm also hoping Toto can send me the replacement flush tower assembly to see if that will fix it & we can replace the gasket at the same time.

Eventually, we are going to get a new taller toilet (an eco Drake) to replace this one and put this one in the guest bathroom once we finish renovating. But that will take awhile.
 
That adjustment is correct.if you needed to adjust there is a plastic rod that rides up and down with the black cylinder by hand you can adjust by turning thd top of the rod clockwise/counter clockwise
 
Thanks, Geof.
Toto referred me to supply.com to get the tower flush mechanism. It's not expensive. However, I found that the Eco Drake ADA height toilet was about half the price that we paid for the current toilet and since my mother has difficulty getting up, we ordered it to replace the current toilet. I may have to figure out how to replace the flange myself if the plumber doesn't call back. I'm not sure if we have 4" lines or 3" lines and if the current flange sits inside or outside of the pipe. I will have to see if I can find the right cutting attachment that will fit my B&D Matrix.

The new toilet has a 16.5" bowl height while the old one had 14.5". We're putting the old one in the new bathroom when we renovate. I'm seriously thinking of pulling the old crappy 40-yr-old toilet that is in the 23" alcove, tossing it outside, and putting the Drake in it's place just to take up less space & have a toilet there. I will also replace the flush mechanism with the tower just to have it upgraded.

Question: If the spud gasket thing between the tank and bowl in the center is messed up, would it allow water to leak out even if the flapper is not leaking?
 
You can just add food coloring to the tank water, to see if water is leaking after the tank is filled.
 

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