Best Epoxy For Toilet Tank Repair

Best Epoxy For Toilet Tank Repair

Anthony Barnes

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Are you looking for the best way to repair your toilet tank? Well, I’ve got some great news for you.

Most toilet problems are very easily fixed and don’t require a professional plumber to perform the repair!

The majority of your toilet problems can be solved using a strong epoxy. Read on to find out how to fix the cracks in your toilet, and which epoxy will be most effective for your individual problem!

What Is An Epoxy?

Epoxy is a class of adhesives. It is used in a wide range of settings, including for metal coatings, structural repairs and in electrical insulators. It can be used to seal cracks and repair leaks. 

Problems With Your Toilet 

Toilets are simple mechanisms that usually don’t take much in terms of repair work. The bowl is made of solid porcelain and rarely needs to be repaired. 

However, you will sometimes run into some problems with the toilet tank as it is prone to malfunctioning and includes more parts than the toilet bowl.

The tank contains two valves, and a flush handle. These are the parts which often have the most problems.

Malfunctions or cracks in the toilet tank can cause leaks on the bathroom floor (see also ‘Finding And Fixing A Leak Under The Bathroom Floor‘) if they are not fixed. 

However, most toilet problems are easily fixed and parts are easily replaced so there’s not much to worry about when it comes to your toilet’s health!

You can replace broken parts easily and repair and seal cracks with epoxy.

Usually, you will be able to fix these things yourself, without enlisting the help of a plumber!

Diagnosing Your Toilet Tank Problem

There are a few different issues you could be having with your toilet. These include:

  • A malfunction with the flush valve
  • A toilet (see also ‘How Does A Toilet Work?‘) that won’t stop running 
  • A loose flush handle that means the toilet won’t flush 
  • Cracks in the toilet tank that are affecting the movement of water

When To Use Epoxy 

When To Use Epoxy 

When your toilet tank has cracks in it, it is essential you repair the problem as soon as possible. There are two ways that you can do this:  

  1. Replace the toilet tank (see also ‘How To Fix A Slow Filling Toilet Tank’)
  2. Repair using epoxy

What Causes The Cracks In Your Toilet?

Cracks in your toilet tank are common and can occur at any time. These causes include: 

  • Natural wear and tear. This is difficult to avoid and occurs due to prolonged use over a long period of time. We use our toilets all day every day so it is natural that wear and tear will occur!
  • During the manufacturing process. Sometimes small cracks occur during manufacturing but they don’t develop into a problem until later on!
  • During the transportation process. Sometimes damage occurs because of wear and tear during the process of transporting the product from the manufacturer to the store, or from the store to your house. 
  • After you drop a heavy object onto the tank. Occasionally, when you drop something on the tank it can cause a crack. This can also occur when the tank lid is accidentally dropped.
  • Extreme temperature changes can also cause cracks.

Diagnosing A Crack In Your Toilet Tank 

The first sign of a toilet tank crack is a leak. When you notice a leak near your toilet, it is important to figure out where the crack is coming from as this will affect the action that you take next. 

If the crack is above the water level you should:

  • Monitor the crack to ensure it doesn’t get worse. It is a good idea to take a picture of the crack so that you can check if it is getting bigger or infringing on the water line. 

If the crack is under the water level:

  • This represents a problem as it can cause leaks and may get worse if it is left untreated. You should fix cracks under the water level as soon as possible. Make sure you’ve checked both the inside and the outside of the tank!

How To Fix A Small Crack 

If the crack in your toilet tank is small, epoxy can easily seal the crack and solve your problem. If you apply the epoxy, you will be able to continue using the tank as before.

Sometimes, if the crack is too large, it will not be repaired by epoxy and, eventually, you may have to replace the toilet tank.

If you notice a crack, you should deal with the problem as soon as possible, you don’t want the leak to cause your toilet to be out of service!

What Should I Use To Fix My Toilet? 

Two-Part Epoxy

Two-part epoxy is most commonly used to fix a crack in your toilet. Two-part epoxy is an adhesive resin mixed with a hardener.

This sealant is waterproof, which is obviously very important when sealing cracks below the waterline in a toilet.

This is a tough adhesive which keeps the crack sealed for a long time. There are a few different types of two-part epoxy. Read on to find out the pros and cons of each.

Epoxy Putty Stick 

This is commonly used for sealing pipes and fixing leaks in tanks or drains. It can be used on lots of different materials and is very easy to use. Use it on wood, glass, ceramic, plastic or metal.

Usually, this product has a 24 hour curing time so your toilet will be out of use for this time. 

Pros: This product is great because it is easy to use, is very strong and is often used by professionals and can be applied to uneven surfaces.

Cons: However, this product is mixed in your hands and applied by hand which can be messy. Like lots of epoxy products, this product has an unpleasant smell and it dries quite quickly.

PC-11 Epoxy Adhesive Paste

Pros: This product is fantastic when working with materials such as ceramic, rubber, concrete and glass. It also has a large temperature range and can withstand both very high and very low temperatures.

It is also a drip-free epoxy, meaning you can apply it to inaccessible areas where other epoxy’s wouldn’t be suitable.

This epoxy is also very strong and resists products that may corrode other epoxy such as fuel, detergents and gasoline. It is very cheap and is reviewed as a great product by users.

Cons: However, this great product can be hard to mix because it is very thick.

If it is not mixed correctly, it won’t work effectively. It sets in a pale green colour and it needs around 24 hours to set hard.

Loctite Marine Epoxy

Loctite is a commonly used brand, and the marine epoxy fluid is commonly used for repairing cracks in the toilet tank.

Pros: Loctite Marine Epoxy is very strong and will not crack when a drill is used on it, it is very durable. This product is waterproof.

It is very easy to mix correctly because the two parts are released from syringes which helps with precision.

This product does not need to be left to dry, you can refill the tank and it will continue to cure under water. The epoxy can also be sanded to leave a smooth finish. 

Cons: However, it takes a while to cure under the water. It is also a visible fix so you may need to apply paint to cover it if the crack was in a visible position.

Applying The Epoxy

Whichever epoxy you have chosen, they are all applied in very similar ways. When applying your epoxy sealant to your toilet, follow these steps:

  • Empty the toilet tank. This is done by first ensuring the supply valve is turned off. To drain the water that sits in the tank, flush the toilet and let it dry. This can take a while.
  • Ensure that you completely dry the toilet with a clean and dry rag. If it is not dry, the adhesive won’t stick to the crack. 
  • Make sure you’re applying the epoxy to a clean surface, ensuring it will stick. Wipe off any debris from the crack and the surrounding area. The area should be perfectly clean.
  • Mix the epoxy depending on the specific instructions that come with the product. Use a spreader or a knife to apply the epoxy. Make sure you apply this as soon as you’ve mixed it as it must be used quickly before it hardens.
  • Apply the epoxy to both sides of the crack, apply plenty because the more adhesive applied, the stronger the hold will be. 
  • Stick duct tape across the two sides of the crack to hold them together until the glue epoxy has set. 
  • Remove any epoxy from the knife before it hardens. 
  • If you think the crack might need more reinforcement, secure the repair with mesh tape, stick it to the tank somewhere that it can’t be seen. 
  • If the crack can be seen on the outside of the toilet, you can apply a ceramic paint so the crack is no longer visible.
  • Finally, wait for as long as the product says it takes to set before refilling the toilet tank with water. Do this by turning the valve back on. Then flush the toilet to check for leaks.

Final Thoughts

When you notice a leak in your bathroom, a very usual response would be to enter panic mode. It is worrying to consider how much money and inconvenience a plumbing problem can cause.

However, sometimes there is a very simple explanation for a leak. This article should help you to identify a crack in your toilet tank and lead you through the process of fixing it yourself. 

Remember, if this doesn’t work or you’re struggling at any time, call in a plumber. You don’t want to cause more problems down the line!

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By Anthony Barnes

Anthony Barnes is the founder of Water Heater Hub and a second-generation plumber by profession. Before developing Water Heater Hub, Anthony Barnes was a full-time plumber, and he has undertaken a wide variety of projects over the decades. As a second-generation plumber, it was easy for Anthony to get used to the technicalities of all from a tender age