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Solution for a Toilet That Keeps Running

In my case it more than quadrupled in ONE MONTH!!!!

I blinked a few times, called the water company and then took my lumps.

Turns out the toilet was running due to a bad flapper valve.

Let’s just say I learned a valuable lesson: if you see water running in the bowl or have to jiggle the toilet handle then chances are good you need to replace the flapper.

Sounds easy, right? It is, but there are a few things you need to know before getting started.

So I’ll show you everything you should know about this easy project.

Here’s your supply list

  • Replacement Flapper (specific to your toilet, don’t worry I’ll show you how to pick one)
  • Wire Cutters
  • Sponge

Here’s what you’ll learn

  • How to choose a replacement flapper for your toilet and install it

I know what you’re thinking, “Jeff, I’ve done this before and this is way easy.”

And you’re correct.

But it’s my duty to show you all the cool stuff that’s out there, including toilet flappers. And I’m betting you’ll learn at least one good trick today.

Pick the right flapper valve, otherwise you’ll kick yourself

Picking the right flapper is like choosing a pair of shoes: you want a good fit.

If shoes don’t fit right you’ll get blisters. If your toilet flapper doesn’t fit your toilet will run or won’t flush properly.

good fit = good results.

One of the reasons flapper valves breakdown and get worn out is bacteria. Pick a flapper that has Microban in it.

In other posts I’ve recommended using bathroom caulk that has Microban. This is because Microban will prevent bacteria from growing on the surface.

Pick a Flapper Valve with Microban

Fluidmaster makes a ton of different kinds of flapper valves. The one above is a universal option that will fit any kind of toilet.

The 501 flapper below is especially made for older toilets (think powder blue or pink, haha) that have 3.5 gallons per flush, aka GPF.

Choose the correct flapper size
3.5 GPF Toilet Flappers

If you have a newer toilet that’s 1.6 or 1.28 GPF then you’ll want to choose Fluidmaster’s 502 flapper.

Fluidmaster Flapper for New Toilets

Each of the flappers I just described have Microban in them. Which is awesome.

Now that you know how to pick a flapper it’s time to install it. I’ve got several tips that’ll help you out 🙂

How to install a flapper valve in 8 minutes and do it the right way 

This tutorial couldn’t be more step-by-step.

I’m convinced that my 11 year old could possibly do it without me. But, then again she still complains about having to tie her shoes.

I could explain everything in pictures but frankly video is way better. So here’s my video and make sure your watch the last 5 seconds – my daughter cracks me up!!

Here’s the summary of all the steps for replacing your flapper valve

  • Hold down the toilet handle to remove most of the water from the toilet tank.
  • Remove the old flapper from the tabs on the overflow pipe and disconnect it from the toilet handle.
  • Clean the flush valve seat with a sponge.
  • Place the new flapper onto the taps of the overflow pipe. Snap the flapper into place and have sit flush on the flush valve.
  • Connect the chain clip to the hole in the toilet handle lever that’s directly above the flapper. You want about 1/2 inch of slack in the chain.
  • Turn the water back on at the shutoff valve and allow your toilet tank to fill. The water in the tank should stop so that it’s 1 inch below the overflow tube.

Once the toilet tank is full of water go ahead and flush it. Check that  the flapper smoothly flips open and closes with no problems.

Your tank should begin to fill with water. Once the water level reaches that 1 inch space below the overflow tube it should shut off and that’s when you know you’ve installed the flapper the right way.

Flush your toilet a few more times to make sure the water completely exits the bowl and you have a strong flush. If you don’t have a strong flush you can add more water to the tank by adjusting the float or if you used the Fluidmaster 502 flapper like me you can adjust it to give you a maximum flush.

What’s Next

Our other tutorial showing how to fix a running toilet has other awesome tips – and might save that call to the plumber!

If you’re doing a bathroom remodel and need help, join one of our online courses – they’ll make your bathroom renovation much easier!

Let me know if you have any questions and I’ll do my best to help.

Thanks as always for reading, watching, and being part of our awesome community.



Running Toilet Quick Fix

  1. Derek Edwards says:

    Hi Jeff, I’ve recently had more time consuming trouble with flappers..starts off with that little whoosh every so often that means waters leaking from the tank,I replaced the flapper and put a few drops of food colouring in the tank to see if the bowl was red the next morning,it was….as you said its SO important to get the right one…..I ordered one from Kohler and they sent the wrong one after three weeks of waiting with no toilet ( they had changed the flapper system) so I ended up taking the entire over flow and the part where the flapper clips on to Lowes and try about ten before I found the right one….a little tip, the universal ones don’t work and it’s so important to get one with the exact same length arms or you will have the same problem that I did….it can be a nightmare,anyway thanks for this great website,I love it Derek

    1. Great tips Derek. It stinks that Kohler sent the wrong flapper, what the heehaw!!!

      I like the food coloring in the tank, that’s a sure way to see if the flapper is leaking.

      And thanks for your advice on getting the right sized arm 🙂

  2. Jim Chapman says:

    How do I know for sure how many gpf the toilet has. Thanx

    1. Hey Jim, it’s usually written on the bowl just behind the toilet seat. If not there it might be on the inside of the tank. If you toilet is super old you most likely have a 3.5 gpf. When I say super old I mean anything pre 1990. Which is weird because that doesn’t seem like it was that long ago. Getting old kinda stinks!!!

  3. Linda S. in NE says:

    Hi Jeff,
    Before I forget, I just realized I have not been receiving your posts even though I have been subscribed for quite some time. I know from other blogs I subscribe to, there is a problem with some blogs with their subscribers not getting current posts. I will wait for your advice, but hopefully it will be something as easy as subscribing again.
    My real reason for writing is that one of the toilets in my house is periodically making a “whooshing” noise, then the distinct sound of water being turned on, water running, and then water being turned off. After investigating, I traced the noises down to a toilet where I can actually see water moving in the bowl at the conclusion of these noises. I immediately though of your site for assistance with this problem, and to keep $$$ in my bank account. I did read your post, and watched the video, and you did make it look easy. I tracked down my brand name of toilet, and found the # for gpf, (1.6) However, I do not see the normal looking flapper w/chain that you show and describe. Instead I have a plastic arm connected to the flush handle, and the other end of that arm slips into a “bracket” on the side of what I can only describe as an “upside-down plastic telescope looking tube” that I am pretty sure is acting as the flapper. (I know, I know,…useless girl help!!). This toilet does not even have the normal float arm in it. To tell you the truth, the back of this toilet is so disgusting looking with the bacteria growth you showed, plus a deposit of something that looks like a pile of black sandy granules, that I am about ready to call in the Haz-Mat team!! I have made no attempt to scout out my local Home Depot, nor Menard’s to see what might be available to help me remedy this problem. I’d much rather hear from you, (someone I can trust) first, and then proceed from there. Looking forward to your reply. Thank You.

    1. Thanks Linda for your question and for subscribing.

      I’ll have to see if your email address is registered and if it isn’t I can add it with your permission.

      With regard to your toilet, maybe you could send me some pics. That way I can give you better assistance. Sometimes it’s the fill valve that needs to be replaced. And I know you can do this.

      I’ll send you an email and you can respond back to it with the pics 🙂

      1. Yvonne says:

        Thanks for your info about flappers bc I just replaced my leaky pump which has cost me an extra $40 on my water bill that I’m choking on to pay!! But I was so confused bc I know my flapper is also bad as my toilet will still not flush good (and yes, all the troubleshooting issues have been checked out & are fine) but the flapper that came w/the one I purchased w/my pump looks nothing like mine. I just didn’t pay attention! In these videos, these all seem to be made of flexible rubber now but mine is hard plastic w/a rubber seal which makes the hole too big for the replacement flapper. Do they sell mine still are larger rubber ones? Thanks for your help!

  4. Terri says:

    Help! I read & watched your videos but we still need some help, please. We have a low boy toilet & the parts inside the tank are different than what we saw on your videos. We need to lower the water level by about an inch as it is too high & keeps on running & leaking. Is it something we can adjust or do we have to buy some new parts? And if so, I haven’t seen similar parts in the store.

  5. Colleen says:

    Hi Jeff- I am a new home owner. I noticed/been hearing my toilet “running” so I had a plumber friend come over to check it out. He said I need a new flapper- gave the type of flapper to get for my type of toilet. This was purchased- the man at the store gave me some tips on how to and also to follow the instructions in the package. I attempted too-however, I did not turn the water off prior. I measure the chain out correctly etc. Once I installed- I doesn’t flush when prompted too? Also, when it does flush- afterwards the water seems to be tidaling/running in the bowl and along the sides and actually sounds so. It did stop running after a while-but I wasn’t able to flush as needed. How did I mess this up??

    1. Hmmm, what kind of flapper did you get Colleen?

      You want a bit of slack in the chain so that the flapper can easily go up and down. If the chain is too tight the flapper will go and down too quick. Plus the fit may not be right on the flush valve which leads to water leaking down into the bowl.

  6. Carolyn McCormack says:

    I am interested in response to Linda S in NE, dated May 18, 2014. I also have the same type of flapper (the plastic arm) Replaced but still getting whooshing noise, just not as often or as loud?

  7. Genevieve says:

    There is a sound of running water similar to when you hear a shower running from the other side of a wall. But when I look in the toilet tank, the water is completely still and nothing seems to be flowing there. The sound definitely sounds like it comes from behind the toilet area. This happened a few months ago and I turned the shut off valve as far as I could to the right and it stopped the sound. The toilet still appears to flush normally. Now I am hearing the sound again; I’ve turned the valve as far as I can but am afraid to push it too far in case it’s ready to break. Do you think the problem could be that the valve is going or can there still be a problem in the tank even though it doesn’t seem like it? This is a bathroom on an upper floor and I don’t see any evidence of water running inside of walls which I hope is definitely not a possibility. Thank you for your expertise!

  8. Judith says:

    I have a one piece toilet bowl. Is the fix for the flapper different? Or would this apply?

    Thanks so much. Happy New Year!!

  9. Kendra says:

    I just installed a new flapper and I still see water running into the bowl. Any suggestions?

  10. Pat says:

    Your videos are most helpful, Thanks.

    I have replaced my flapper and it continues to close too early to complete the flush. Several adjustments to the chain have not solved the problem. The handle is mounted on the left side of the toilet ( facing the toilet ). The handle appears to be too short as it is not directly over the flapper, it has worked previously for years. Any suggestions?

    Thanks, Pat.

  11. dannybrooks says:

    water runs in in the night just a little put a new flapper on

  12. Scott eustice says:

    I toilet was running off and on… I inspected the flapper and found that the white seal ring just under the flapper had developed raised water blisters. I used a pin and popped them…Squished the water out of them and put it back on. No more leaking!

    1. Thanks Scott for adding that tip. It sounds like that flapper will need to be replaced though. It’s not a bad idea to get a replacement. I like the Korky line but try to find a flapper that matches your existing one.

  13. Sharon McBride says:

    I have a very old kidney bean toilet. Very old but VERY cool! I replaced the flapper with a genuine replacement for that type toilet. Was great for a year or so. But now it leaks a little and periodically runs enough to fill back up. I can fiddle with it after flushing and sometimes it is fine. Very annoying and uses water I unnecessarily. What can I do?

    1. Thanks Sharon for sharing. Did you get a flapper for that specific brand of toilet, e.g. American Standard or Toto?

  14. Kitty says:

    Hi Jeff,
    So what could the problem be if i changed the flapper to the same one you did and all worked great for about a week but now my toilet is running again and i can’t seem to find the issue. Could it be the flush valve? The water just never stops filling and runs into the overflow pipe and bowl. I have to keep it off when i’m not using it. I am trying to not call a plumber and fix it myself if i can. What do you think could cause it to stop working after just a week?

  15. Jeanette says:

    Hi, your videos are great. Simply and easy. My issue is my flapper keeps getting stuck on that ball that sits on top of the water.

  16. Francesca Dixon says:

    Has anyone invented a toilet that will never run? This seems like stone-age technology.

    1. Hey Francesca, you’re totally right. Not sure why toilets haven’t been upgraded, still the same old system for most affordable toilets.

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