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How to Replace Cracked Toilet Tanks

Cracked toilet tanks can be a real hassle for homeowners. Not only are they unsightly, but they can also lead to leaks and water damage. This article will provide a step-by-step guide on how to replace a cracked toilet tank.

We will cover everything from assessing the damage to gathering the necessary tools and materials, replacing the tank, and maintaining it.

By the end of this guide, you will be equipped with all the knowledge you need to replace your cracked toilet tank successfully.

Assessing the Damage

Types of Cracks that Can Occur in Toilet Tanks

When assessing the damage to a toilet tank, it’s essential to identify the type of crack that has occurred. Several types of cracks can occur in toilet tanks, including hairline cracks, complete breaks, and cracks around the mounting bolts.

Hairline cracks are small and not always visible to the naked eye. Full breaks, however, are significant and often result in leaks. Cracks around the mounting bolts can occur if the bolts have been over-tightened, causing the porcelain to crack.

How to Identify if a Toilet Tank is Cracked

To identify if a toilet tank is cracked, you can run your hand over the surface of the tank, or you can use a flashlight to examine it more closely. If you cannot see the crack with the naked eye, you can also check for leaks or water damage around the toilet’s base.

Determining the Severity of the Crack

Once you’ve identified that a crack is present, it’s essential to determine the severity of the crack. A small hairline crack may not require immediate replacement, whereas a large full break will. It’s necessary to address any cracks as soon as possible to prevent further damage and potential leaks.

Safety Precautions

When working with plumbing, taking the necessary safety precautions is essential. Always shut off the water supply before assessing or replacing a toilet tank. It will prevent water from flowing into the tank while you’re working on it.

Also, make sure to wear gloves to protect your hands from any sharp edges or debris. And always be sure to proceed with caution when assessing the damage or replacing a toilet tank to avoid accidents.

Preparing for the Replacement

Gathering Necessary Tools and Materials:

Before replacing your cracked toilet tank, gathering all the necessary tools and materials is essential. You will need a new toilet tank, a new jamb nut, an adjustable wrench, and possibly a new supply line. It’s also a good idea to purchase a new wax ring and mounting bolts. Make sure to have all these materials ready before starting the replacement process.

Cost and Materials

It’s essential to have an estimate of the cost of the replacement and the materials. It will help you budget for the replacement and avoid any unexpected expenses. Check for any warranties or guarantees on the materials you purchase. You need to return or exchange them.

Shutting off the Water Supply

Before beginning the replacement process, shutting off the water supply is crucial. It will prevent water from flowing into the tank while you’re working on it. This step is vital for safety and to avoid any water damage.

Emptying the Tank

The next step is to empty the tank. It can be done by flushing the toilet several times until emptying the tank. It will make it easier to remove the old tank and install the new one.


Before starting the replacement process, it’s important to troubleshoot any potential issues that may arise. It could include checking for leaks or loose connections in the current tank or identifying potential problems with the new tank or materials. Troubleshooting beforehand can save time and resources in the long run.

Replacing the Tank

Step-by-Step Instructions:

  1. Test whether the jamb nut holding the tank’s supply line is loose.
  2. If it is, use an adjustable wrench to tighten the nut.
  3. Proceed carefully, as the nut and fitting are likely made of nylon and can strip when over-tightened.
  4. The porcelain tank is also susceptible to cracking from the pressure of over-tightened nuts.
  5. The nuts should be snug, only a quarter turn past hand tightening.

Removing the Old Tank

  1. Once the jamb nut is tightened, remove the mounting bolts that hold the tank to the bowl.
  2. Be sure to carefully remove the nuts and bolts, as they may be rusted or corroded.
  3. Once the nuts and bolts are removed, lift the old tank off the bowl.

Installing the New Tank:

  1. Before installing the new tank, place the new wax ring on the bowl’s rim.
  2. It will help to create a watertight seal between the tank and the bowl.
  3. Once the wax ring is in place, set the new tank and secure it with the mounting bolts.

Reconnecting the Water supply

  1. Once the new tank is securely in place, reconnect the water supply.
  2. This can be done by attaching the new supply line to the tank and securing it with the jamb nut.
  3. Be sure to tighten the nut just enough to create a watertight seal.

Testing for Leaks

  1. After reconnecting the water supply, turn it on and check for any leaks.
  2. If there are no leaks, proceed to the next step.
  3. If there are leaks, check the connections and tighten the nuts again.


Replacing a cracked toilet tank can take anywhere from a few hours to a full day, depending on the crack’s severity and the task’s complexity. It is essential to have all the necessary tools and materials on hand before beginning the replacement process, as this can help to streamline the process and minimize the time frame.

DIY vs. Professional

Many homeowners choose to tackle the task of replacing a cracked toilet tank on their own as a DIY project. However, for those who are not comfortable with plumbing or are unsure of their abilities, it may be best to hire a professional plumber to handle the task.

Hiring a professional plumber can ensure the job is done correctly and save time and money in the long run. Additionally, experienced plumbers are well-equipped with the right tools and knowledge to tackle any problem.

It is essential to remember that a cracked toilet tank is a serious issue and should be addressed as soon as possible. Not only can it lead to leaks and water damage, but it can also be a safety hazard. Whether you tackle the task on your own or hire a professional, follow all safety precautions and instructions carefully to ensure the job is done correctly.


Tips for Maintaining a Toilet Tank

  1. Regularly check the jamb nut that holds the supply line to the tank to ensure it is tight.
  2. Use a wrench to tighten any loose nuts or fittings.
  3. Never over-tighten the nuts and fittings, as this can lead to stripping or cracking of the porcelain tank.
  4. Clean the tank and bowl regularly to prevent the buildup of minerals and bacteria.
  5. Flush the toilet regularly to ensure the proper functioning of the flush mechanism.

How to Identify Potential Issues Before they Become Major Problems

  1. Look for signs of leaks around the base of the toilet or on the floor.
  2. Listen for any unusual noises coming from the tank or bowl.
  3. Check for cracks or chips in the porcelain tank.
  4. Pay attention to the water level in the tank. If it is low or fluctuating, this can be a sign of a problem.
  5. Be aware of any changes in the color or smell of the water in the tank or bowl.

Tips and Advice

  1. Regularly inspecting and maintaining your toilet tank can help to prevent significant problems and prolong the life of your toilet.
  2. If you notice any issues, address them as soon as possible to avoid costly repairs.
  3. Always use caution and proper safety precautions when working on your toilet.
  4. If you need help with your abilities or the problem is complex, consider hiring a professional plumber to handle the task.
  5. Proper maintenance can help to prevent the need for costly repairs and replacements in the future.

By following these tips and advice, you can help to ensure that your toilet tank stays in good working condition for years to come.

Remember to pay attention to any potential issues and address them as soon as possible to prevent costly repairs and replacements. And always use caution when working on your toilet, and hire a professional if you need clarification on your abilities.

Summary of the Steps for Replacing a Cracked Toilet Tank

  1. Test whether the jamb nut holding the tank’s supply line is loose.
  2. Use an adjustable wrench to tighten the nut.
  3. Remove the old tank and install the new tank.
  4. Reconnect the water supply and test for leaks.
  5. Maintained the toilet tank by regularly checking for leaks, listening for unusual noises, and cleaning the tank and bowl.

Reminder to Always use Caution and Proper Safety Precautions When Working with Plumbing

It is important to remember that working on a toilet tank or any other plumbing can be dangerous if proper safety precautions are not taken. Always use caution and follow appropriate instructions to ensure the job is done safely and correctly.

Additional Resources for Further Information:

  1. The American Society of Plumbing Engineers (ASPE) provides information and resources for plumbing professionals.
  2. The International Association of Plumbing and Mechanical Officials (IAPMO) offers training and certification programs for plumbing professionals.
  3. The National Association of Plumbing-Heating-Cooling Contractors (PHCC) provides resources and training for plumbing professionals.


In conclusion, this blog post has provided an overview of the steps involved in replacing a cracked toilet tank. We hope that this guide has been informative and helpful.

If you are unsure of your abilities or the task is complex, consider hiring a professional plumber to handle the job. And always use caution and proper safety precautions when working on your toilet.