Toilet Tank Leaking At Bolts: Tips for Repairing It

Many houses have a two-piece toilet, which is composed of two parts: the bowl (which is what people sit on) and the tank (which stores water that will flush the toilet). These two parts are connected to each other through a set of bolts, which pass through holes at the bottom of the tank and a matching set of holes in the ridge of the bowl. These bolts usually won’t cause problems but, if they’re improperly installed or are damaged, they can lead to serious leaking.

Leaking bolts are usually identified by the presence of water droplets on their ends. Slow leaks can also be noticed since there would be water on the floor under the tank. If you suspect that your toilet tank is leaking at the bolts, you can take the following steps:

Inspect The Bolts and Other Parts

The first thing you should do is to check if the bolts are properly installed. They should be properly and equally tightened; if they’re not, this can cause the leak. Tighten the bolts if you see that they’re too loose.

Don’t forget to check the rubber washers, too. These parts can degrade as time goes by, so they may already be damaged if it’s been years since you replaced them or if you haven’t replaced them at all.

Take a Close Look at the Tank

Sometimes, the problem lies not with the bolts themselves but with the toilet tank. One scenario is when there’s a crack or several cracks around the bolt hole. If this is the case, you will always have a leak even if you’d replace the bolts or rubber washers, and you’ll need to replace the tank. Take note that even a hairline crack around the bolt hole can already cause a significant leak due to water pressure.

You should also ensure that the tank sits on the ridge of the bowl. Proper placement of the tank is usually needed to create the right amount of water pressure that will compress the rubber washers and make a seal against leaks.

Replace the Bolts, Nuts, Washers

If you’ve checked the bolts, nuts, or rubber washers and found out that they are defective, you’ll need to replace them to stop the leaking. Even if only one of them was defective, it’s a good idea to replace all the parts at the same time so you can deal with the problem all at once instead of having to go through the process several times. You can start by taking these steps:

1. Purchase the correct parts from the hardware store. Check your toilet’s manual to know the exact model numbers of the parts you need to buy.

2. Turn off the water supply to the toilet.

3. Flush the toilet to remove the water that’s stored in the tank, and use a sponge to remove the remaining water in the tank.

4. Remove the tank lid and set it aside in a safe place.

5. Remove the slotted screws at the bottom of the tank. Depending on your toilet, you can either do this by hand or use an adjustable wrench to do so.

6. Take out the old bolts, nuts, and washers. Take note of their position so you can install the new ones the right way. You may need to use a hacksaw blade or even a drill if the bolts won’t easily unscrew, but be careful when using this equipment to avoid damaging the tank.

7. Install the new bolts, nuts, and washers. Return the slotted screws and put the toilet lid back on.

8. Turn on the water shutoff valve to let water into the tank. Check for any leaks and tighten the nuts as necessary.

Use these tips now to stop the leaking from the bolts of your toilet tank.

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