How to Test a Toilet for Leaks – Home 101

This is a quick, fun video that gives you some advice on checking to see if your toilet needs the entire valve replaced or just the flapper. You may want to look into this if you have a toilet that seems to run on and on. Food coloring is the only thing you need here. You simply put some in the top of the toilet and let it sit for 25 minutes. When you come back and there is colored water in the bowl, then it is the flapper and that is a good thing. That means that you only need to replace that rather than the whole valve. It also gives you a tutorial on what the mechanisms are in the top of the toilet. Rather than saying to the hardware store you need a new “thingy”, you’ll actually know what part you need.


Hey everyone! It’s a special day here. This episode is just one in the series about the magical bathroom toilet. I’m not even gonna touch that one. All jokes aside Joel, the toilet is something that sees a lot of use in a house and problems can arise from time to time. One of the biggest bathroom issues is a toilet that runs on after flushing or starts running or flushing by itself. Like a possessed porcelain poltergeist. If left untreated, this can really run up your water bill. We’re going to show you fixes, but if it doesn’t work, you may be in need of a new toilet altogether.
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Typically, problems like these are rooted in the tank and have to do with water level in here. If the water level is above this overflow pipe, then the fill valve or ball cock right here isn’t working properly or it’s set to the wrong height. If you’ve just installed a new one of these buggers, it’s going to look like this.
Make sure that the water level has been adjusted to the manufacturers recommended level which is usually stamped inside the tank. If the internal diaphragm seal is worn or damaged, you’ll need to replace it. It looks like this. If the seal isn’t available for your type of valve, you’ll need to replace the whole fill valve. If you see in the tank the water level remains below the overflow pipe when filled, you probably have a worn out flapper which is here.
If the flapper is leaking, it will keep triggering the fill valve to refill the tank. So here’s an easy test to see if your flapper is faltering. Put a few drops of food coloring into the tank and give it 25 minutes.
Ok, let’s check the bowl to see if any of the color made it through. Hmm, the food color has seeped into the bowl telling us that this here flapper is indeed forlorn. Before you replace it, check the valve seat under the flapper for a sediment or debris that might be keeping it from sealing tight, but the good news is, if you need to, you can replace the flapper which is a lot cheaper than replacing the whole valve.

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