Toilet Leaking Between Tank and Bowl [6 Easy Steps To Solve It]

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Annoyed at having to look down at your feet and find a puddle? Well, it’s probably because there is a leak in your toilet between the tank and bowl.

Why is your toilet leaking between the tank and bowl?

There are several reasons as to why there is a leak. Mainly this has to do with your gasket screws or seal malfunctioning. Before you get into the solution, it’s ideal to identify the location of the leak first. This will help you solve the issue better.

We know this isn’t enough for you. We’ve gone deeper into this problem, so keep on reading. 

Identifying The Leak’s Location

Intense pressure from the water supply and inlets may cause leaks. Improper rough-in measurements of the toilet may lead to stress-buildup in pipes and cause leaks as well.

The initial step to identifying the problems is the same. You have to use dyed water to trace the leaks for you. We recommend using a bright-colored dye, such as red or blue.

Start by lifting the tank lid and add some colored tablets. You could also use organic dyes such as food coloring. After adding the dye, wait for 10-15 minutes for the color to settle. Do not flush the tank yet. 

From then on, the dyed water will indicate where the leak is coming from.

Cause Of The Leak

Once you’ve identified the location, it’s important to know the cause of the leak. Leaks can occur for many reasons. Look for the following problems and identify your cause to fix them.

Tank Sweat

This is the least serious issue when it comes to leaking. This does not require a dye test.

This occurs due to a temperature difference. The water on the inside is cooler than the surrounding air outside. As a result, water condenses on the outside and drips down.

Tank-To-Bowl Washers & Bolts

The tank-to-bowl washers are the rubber seals on the tank-to-bowl screws and bolts. Rusty bolts are responsible for leaks outside the tank. 

Tank-To-Bowl Sponge Gasket

If the dyed water drips from the center, it could be due to the faulty gaskets. This is the circular rubber seal outside the main pipe feeding the tank. It’s on the outside of the tank. 

Leaks due to this tend to occur after flushing the toilet.

Shank Gasket Malfunction

Shank Gasket malfunctions due to cracking may lead to improper flushing causing clogs. In this case, you’ll need to unclog your lavatories.

The shank gasket or the ballcock gasket, and the fill valve are linked on the inside of the tank. The colored-water test should also determine the leak for this.

Cracks In the Ceramic

This is the easiest to detect from the bunch. If there is a crack in the ceramic tank, water should spill from there.

Refill Tube Issues

This is when the leak comes from the back of the toilet bowl. More precisely the lower back portion of the tank.

This could be due to a loose refill tube connection or a faulty refill-tube ring. Faulty refill tubes result in your toilet not filling up with water.

Fixing The Leak In 6 Steps

All these problems have the same solution except Tank sweats and cracked porcelain bowls. We’ve provided the solution to these 2 problems. We’ve also curated a 6 step process for the rest of the problems. 

For Tank Sweats 

Tank sweats can be easily tackled by Anti-Sweat tank valves/toilet tank liners. Toilet tank liners insulate the cold water from the outside. Anti-sweat toilet tank valves mix the cold and warm water in the tank. This stops the water from leaking.

For Ceramic Cracks

Ceramic cracks are a terminal diagnosis. If you have cracks in your ceramic bowl, replace your toilet.

The steps needed for the rest of the problems are mentioned below-

Since you’re working around slippery surfaces, use slip-resistant work shoes.

If you can’t choose between shoes, we recommend these two-

Shoes-1
Shoes-2

Step 1: Turn Off Supply

First, turn off the water supply from the inlet valve. Then drain the tank by flushing out the water.

Step 2: Empty Out The Tank

Now, place a bucket under the tank for the leaks. There will be some water left at the very bottom. Use a rag to mop it up or a siphoning pump to get the water out.

Step 3: Unscrew The Tank

Next, disconnect the water supply valve and unscrew the joining bolts. This will free your tank and it should wobble at this point.

Step 4: Lift The Tank

After separating the tank from the bowl, lift the tank carefully. Remove the Sponge gasket at the bottom and inspect for any faults.

Step 5: Replace The Faulty Parts

This is the step where you have to pay attention. Your toilet could have all of the problems above or one of them.

After identifying the problem or cause, follow the solutions mentioned below.

Washers and Bolts

Carefully inspect whether or not there are any rusty bolts. If there are, replace them with new ones.

Next, check the outside and inside seals on the washers. If the rubber fittings are cracked or faulty, replace those too.

Sponge Gasket

The Sponge Gasket is the rubber cap on the outside that you removed. If this is the faulty part, remove and replace this.

Carefully inspect the bolts surrounding it to see if they are faulty as well.

Shank Gasket

This is the rubber cap on the inside of the tank near the valve. If this seal is cracked, remove and replace it.

Refill Tube

There is a rubber seal on the bottom of the refill tube. If this ring is faulty, remove and replace it.

Step 6: Set The Tank and Finish Up

Carefully place the tank in the basin. Attach the tank to the bowl using the bolts, rubber washers, and hex nuts. Use an adjustable wrench to fix it in place.

Apply downward pressure to maintain the tank level. Meanwhile, tighten the nuts until the tank is stable.

Don’t over tighten the nuts or the porcelain will crack. Next, run the water supply and you’re done!

This is how you fix a leak between a toilet’s tank and bowl. 

FAQs

Question: What is the reason behind my toilet being on top of a platform?

Answer: The platform acts as an elevation for the sewer pipe to run down to the sewer line and up the black tank.

Question: Is my toilet supposed to be level or wobbly?

Answer: Your toilet is supposed to be level at all times or there might be leaks too.

Question: What is the average lifespan of a wax ring?

Answer: Wax ring seals typically have a lifespan of about 30 years or more.

Conclusion

Hopefully, now you can sort your problem regarding toilet leaking between tank and bowl. We sincerely hope our tips came to the rescue for you.

Stay safe and good luck fixing your toilet!

Melissa Hawkins
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