How To Fix a Cracked Toilet Tank

A toilet tank is designed to withstand water pressure for as long as possible. But despite our best efforts to keep it from developing any cracks, the truth is that they do appear over time, particularly hairline cracks in the glazing. The key thing to remember is this: take action straight away when it happens. Don’t wait for water to penetrate the glazing because then, that would be too late; what once was a simple repair job is now a full-on replacement.

Then again, there are occasions when accidents happen and your toilet tank does get cracked. For instance, you dropped a heavy object on the tank or you dropped the lid when trying to put it back on. This is quite a normal situation and luckily, one that can be remedied without resorting to professional help.

While it’s always best to hire assistance from a plumber, you can save a lot of money and time by fixing up issues that can be solved on your own. This article will guide you on fixing your toilet tank when it gets cracked.

When Your Tank Cracks

Your tank may start leaking water when it cracks. Then again, it depends on how badly it was cracked. A minor crack may not lead to your tank leaking but a major one (like the one caused by a heavy object falling on the tank) might send your tank leaking.

Cracks that are bad enough to cause water to leak should be fixed immediately. The last thing you want is to have your toilet replaced as the solution – that would be much more costly than remedying a broken tank. It even gets worse when you live with many people because one broken toilet can spell disaster for the entire household.

What You Will Need

When working on your toilet, it’s best to have all the materials you need available and within reach. The last thing you need to be doing while performing a repair is running back and forth from the bathroom to get what you need. That said, here are the materials you will be needing for fixing your toilet tank:

  • Waterproof Silicone Plumbing Epoxy
  • Caulking Gun
  • Putty Knife
  • Chamois Cloths, Towels, Sponges
  • Electric Hair Dryer

Fixing a Cracked Toilet Tank

Here’s a guide on how to fix a cracked toilet tank:

1. Turn off the water.
Although you can opt to skip this step when you don’t find water leaking, it’s still advisable to turn the water off. This also applies to whatever fixes you might be doing on your toilet. Shutting off the water supply is a wise decision because the last thing you want is for water to be spraying everywhere and making a mess of things.

A cracked tank will leak water and this will spread to the floor. So if you don’t turn off the water before starting to work on your tank, you might end up with more issues than what you started with. Besides, it doesn’t take long to turn the water off. There is water shut off valve that is usually located behind the toilet and turning that off doesn’t take five minutes.

2. Dry the inside of the tank.
You will need to apply a sealer to your tank to fix the cracks and if the area is wet, the sealer won’t dry. This is why you should really take all the time to make sure the tank is really dry before you start working on it. The last thing you want is for everything you worked on to result to nothing because the sealer couldn’t dry.

Yes, the drying part may not be so fun but it’s a necessary step. You can use any kind of material that absorbs: chamois cloth, sponges or towels. To be more sure, wipe down the outside of the tank as well to avoid condensation. You can even be more ruthless by using an electric hair dryer to dry the tank out completely after you’ve wiped it with cloth or a sponge.

3. Apply silicone plumbing epoxy to cracked area.
You can easily find an epoxy sealer at a Home Depot. If that’s not available, you can always use any porcelain sealer. There are so many brands out there that you might end up getting confused. So for the best results, ask a plumbing expert for their suggestion on the right brand to use.

Keep in mind that you might need a caulking gun depending on what kind of sealer you got. If using a gun, fill it with the sealer then get started on fixing the cracks. The best way to go about it is to start an inch above the crack then work all the way down to fill the crack with the sealer.

4. Smooth the sealer out.
Use a paper knife, a putty knife or any other tool that can spread the sealer over the crack. Doing this helps the toilet look good even when you’ve applied something to the cracks. Also, spreading the sealer keeps other areas from cracking.

5. Allow the silicone epoxy to dry.
Let the application stay for at least 24 hours so that it really gets dry and seals up the cracks. But you can also observe the areas you sealed frequently to see how they are doing. Doing this also helps you see other glazing cracks. If you find that no other cracks have appeared since you’ve applied epoxy, you can start filling your tank with water.

6. Refill the tank with water.
Turn the water back on and restore water supply to the tank. Once the tank has filled with water, check again to see if leaks still occur. In case you still notice some leaks, you will need to drain water from the tank again and observe the repaired spots again. Or, check to see if you have missed any other spots.

Toilet tanks are built with durability and quality in mind but that doesn’t mean it will stay strong forever. Time will eventually prevail and we just need to take action to make sure the problem doesn’t escalate.

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