When replacing a toilet flapper, begin by shutting off the flow of water to the toilet tank. Then, flush the tank to empty it. Once the toilet tank is empty, remove the toilet tank lid and find the flapper—it is usually a colored rubber or plastic object at the bottom of the toilet tank. Remove the old flapper by unhooking it from the posts on the toilet fill tube. Purchase a new flapper, making sure it matches the style of the old flapper. Install the new flapper by hooking it onto the fill tube posts. Now, you can resume the flow of water to your toilet tank and use your toilet as usual.
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How Do You Know if Your Toilet Flapper is Leaking?
If you have a leaking toilet flapper, your toilet will usually fill periodically between flushes. This may be evident from the sound of the toilet running even when it has not been flushed recently. Other times, toilets will be silent as they fill due to a leaking flapper. In these cases, look for a telltale ripple on the water in your toilet bowl—this occurs when water trickles down from the tank due to a leaky flapper. A leaking flapper may also cause increased corrosion, buildup, and stains in your toilet bowl.
- Your toilet tank refills between flushes.
- You hear your toilet running when it has not been recently flushed.
- The water in the toilet bowl ripples periodically, as water leaks past the flapper into the bowl.
- Perform a food-coloring test to see if your flapper is leaking.
If you suspect your toilet flapper is leaking, take the top off your toilet tank and put 5–10 drops of food coloring into the water in your toilet tank. Do not flush the toilet. Wait 1–2 hours. If the water in your toilet tank begins to turn the color of the food coloring, your flapper is leaking. A leaking flapper needs to be replaced to solve the problem.
7 Steps to Change Your Toilet Flapper
Replacing a leaky toilet flapper is a quick job that can be tackled yourself, even if you don’t have any experience with plumbing. Just follow these steps.
Close the Water Line to the Toilet
Begin by locating the water line that feeds your toilet tank. This line usually starts from the floor behind your toilet, but it may come from the wall in some cases. Look for an oval-shaped valve handle on this line. Twist the valve to the right (clockwise) to close it. You do not need a wrench to tighten this valve. Turning it by hand is enough.
Flush Your Toilet
Remove the tank lid from the top of your toilet and set it down on a towel, in an out-of-the-way location. Then, flush the toilet. Watch the water level in the tank. It should drop and not refill. If the tank starts to refill with water, tighten the valve on the water line flowing into the toilet until the water stops. Then, flush your tank 2–3 times until it is empty.
Locate the Flapper
To find your toilet flapper, press the flush handle of your toilet. When you do, the flapper should lift up. Look for a semicircular rubber or plastic flap on the “floor” of the toilet tank. In many cases, toilet flappers are red, but they can be blue, black, or gray as well. If you cannot locate the flapper, your toilet may have a flush valve instead. This requires a different repair for a leaking toilet. If your toilet does have a flapper, move to the next step.
Remove the Flapper
Toilet flappers come in a few different styles. In almost all cases, loops or hooks on the flapper attach to two posts on the bottom of the fill tube. By following these steps you can remove any toilet flapper you encounter:
- Detach the flapper chain from the top of the flapper.
- Locate the ears on either side of the flapper, which attach to posts on the fill tube.
- When removing a rubber flapper, pull one of the “ears” on the side of the flapper outward until it slips off the post, then repeat for the other side.
- Use special steps to remove a hard plastic toilet flapper.
- If your flapper has a loop that passes around the fill tube, slide the flapper up until it is fully removed.
- Do not throw out the flapper—you’ll need it when buying a new one.
Always work as gently as possible when removing a toilet flapper. Although you may need to use pliers to open a chain loop and unhook it from the top of the flapper, avoid using tools to pry the flapper loose from the fill tube. Doing so risks cracking the fill tube or breaking the posts.
Purchase a Replacement
Take your old flapper with you when you go to buy a new one. Most hardware stores have a selection of flappers in different styles. Choose one that is similar in style to your old flapper. If you can’t find a match, this universal toilet flapper works on almost all toilet models. If you’re in doubt, ask a store employee for assistance. If you have your old toilet flapper with you, they can use it to help choose a new one that fits.
Install Your New Flapper
Installing a new toilet flapper is often easier than removing the old one. That said, there are still ways to ensure the job goes smoothly. Follow these steps:
- Review any instructions that come with your new toilet flapper and follow them.
- If your new flapper has a ring that is meant to go around the fill tube, fit the ring over the top of the tube and slide it downward.
- For soft rubber flappers, bend one ear outward to fit the post into the hole in the flapper ear. Repeat for the second ear.
- For hard plastic flappers, place the hooked ears over the posts on the fill tube and press down gently until the flapper ears click into place on both sides.
- Attach the flush chain to the loop on the top of the new flapper.
- If necessary, use pliers to bend the hooked end of the chain so it does not come loose from the flapper.
Similar to removing a flapper, installing a new one does not require a lot of force. Exert gentle, even pressure whenever you are bending a flapper ear or snapping a hooked flapper into place. This will make for a disaster-free installation.
Open the Water Line to Your Toilet
Now that your new flapper is installed, turn the valve handle on the water line to the left (counterclockwise) to open it. Then, look inside the toilet tank to ensure it is filling. Test the flapper by flushing the toilet. If the flapper is not opening and closing properly, adjust the length of the flapper chain until it is working correctly. Then, you can put the lid back into place on top of your toilet tank and resume using the toilet.
Why Does Your Toilet Flapper Keep Leaking?
Your toilet flapper is most likely leaking due to age. Many flappers are made of rubber or plastic. These materials crack, shrink, or become brittle with age. A toilet flapper that is leaking due to age must be replaced.
- Toilet flappers are made of materials that break down as they age.
- Once your toilet flapper shrinks or cracks, it will begin leaking.
- Age-damaged toilet flappers must be replaced.
- Toilet flappers may leak due to buildup on the flapper.
- Clean off mineral or algal buildup to see if it stops your flapper from leaking.
Sometimes, mineral buildup or algae growth can cause a toilet flapper to close improperly. If you see buildup on the flapper, clean it off with a sponge and cleaning solution. Then, recheck the operation of the flapper. If it is no longer leaking after you clean it, you do not need to replace the flapper.
How Do You Replace a Leaking Toilet Flapper?
To easily replace a leaky toilet flapper, just follow these steps:
- Close the valve handle on the water line feeding your toilet tank.
- Remove the toilet tank lid and flush until the tank is empty.
- Find your toilet flapper by pressing the flush handle down—the flapper will lift up.
- Remove the flapper by gently pulling it off the posts connecting it to the base of the fill tube.
- Purchase a new toilet flapper that matches your old flapper.
- Install your new flapper to the fill tube posts and the flapper chain.
- Open the water line valve to fill your toilet tank.
This simple process will transform a leaking toilet into a leak-free, functional toilet. You won’t be bothered by a toilet that runs periodically and you will eliminate wasted water.