Toilet Leaks When Flushed

Toilet Leaks When Flushed

Sometimes you’ll run into a situation where your toilet leaks when flushed. There are a few different potential causes of the water leaking.

Depending on the cause, you may be able to create a DIY solution. If you can’t find the source of the leaking toilet, you might need to call a plumber for help.

The first thing to do is to determine what is causing the leaky toilet. Where is the water escaping?

Is it coming from the bottom of the toilet tank, the base of the toilet, or somewhere else entirely?

Leaking Between The Bowl and Tank

Leaking Between The Bowl and Tank

If the leak occurs between the toilet bowl and the tank, these are some potential causes:

  • The gasket between the toilet tank and the bowl is worn out.
  • The tank bolts have become loose.

Leaking At The Base 

Leaking At The Base

If the leak occurs at the base, the cause is usually a faulty wax ring. You’ll need to install a new wax ring with a better watertight seal.

The toilet bowl may also be slightly cracked, leading to a leak. If the crack is big enough, it will keep water from staying in the bowl.

Your bathroom will begin to smell terrible from the contents on the bathroom floor. At this point, you may need to replace the toilet entirely.

Tools Needed for Homeowners Troubleshooting a Toilet Leak

These tools will help with most toilet repair projects involving a leak:

  • A new rubber seal
  • A new gasket to connect the tank to the bowl (including washers and bolts)
  • A flathead screwdriver
  • An adjustable wrench
  • A putty knife
  • A bucket
  • A sponge
  • Newspapers to protect the floor
  • An old towel
  • Rubber gloves to protect your hands

You won’t need all of these tools for certain fixes. But if you’re missing any necessary ones, you can generally pick them up at your local hardware store.

Fixing a Toilet Base Leak

Fixing a Toilet Base Leak

If your toilet flush causes water to leak out around the base, the issue is almost certainly the wax ring. In this case, you might not notice water on your bathroom floor.

But there will be water damage to the ceiling on the floor below the toilet.

The wax ring creates a seal that prevents the water from leaking. To replace it, you’ll need to move the entire toilet. Here’s the basic step-by-step process.

1. Turn off the water supply and empty the tank.

With any fix, your first step is to cut off the water supply line. This will prevent more water from leaking out of the pipes as you work.

The shut-off valve for the pipe should be on the left side of the toilet, on the back of the tank. Turn this clockwise with your fingers.

Next, you’ll need to drain your tank. You can do this with a basic toilet flush.

Take the tank lid off and hold down the flush lever to get rid of as much water as possible.

Some water will remain in the tank. You can soak it up with the sponge and then put the sponge in the bucket.

Disconnect the water supply line from the tank. If you can’t disconnect it using just your fingers, then you can use your adjustable wrench to loosen it.

2. Move the toilet.

Make sure you’ve drained the tank and soaked up any remaining water in the toilet bowl. Using your gloves, soak up the water with the sponge and wring it out in the bucket.

This will prevent a mess when you move the toilet.

Your toilet will be bolted in place. Remove the bolts with your wrench.

If there are caps over them, use the screwdriver to lift the caps first.

After the bolts have been removed, you can rock the toilet slightly so that the seal breaks. Then lift the toilet and put it down on the newspapers.

It’s possible for gases to escape from the sewer and into your home through the open drain. To prevent this, stuff your old towel into the drain to plug it.

The toilet’s wax ring is not reusable, so you’ll need to replace it. To get rid of the old ring, use your putty knife to scrape away all the remaining wax and caulk.

While you’re here, check the toilet flange. Flanges wear down and break over time.

If yours needs replacing, it’s easiest to do while the toilet is not installed.

3. Put the new wax ring on.

Putting the new wax ring in place is relatively simple. You’ll just move the wax into the place where the toilet sits.

It should create a watertight seal around the edges.

One tip to slide the ring more easily is to warm it up first. You can do this by leaving it in a patch of sunlight or dipping it in warm water.

This will make the wax more malleable.

Some people may choose to use a rubber seal instead. Rubber seals can typically be reused, and they may last longer.

A rubber seal should be installed atop the flange. There are holes for bolts to secure it.

4. Put the toilet back and connect the water.

Now you’ll take the towel out of the drain. Lift your toilet up and hold it above the flange.

Lowering it slowly, line the bolts up with the toilet holes. This process is often easier if you have someone around to help.

After you’ve aligned the toilet on the flange, rock the bowl slightly in place and push down. This will attach it to the wax seal.

You’ll then put a nut and washer on the bolts, tighten them with the wrench, and place any required caps over them.

With the toilet in place, you can connect the supply line to the tank. Then you can open the shut-off valve so the tank and bowl fill up.

Flush your toilet a few times and check for any leaks. If you don’t see any, your issue should be solved.

Fixing a Toilet Tank Leak

Fixing a Toilet Tank Leak

The other most common place to find a leak is between the toilet tank and the bowl. This happens as water is flowing from the tank into the bowl when the toilet flushes.

It is usually caused by a broken gasket. Poorly-sealing gaskets also cause wobbly tanks.

You’ll need to remove your tank and replace the gasket by following these steps:

1. Drain and empty your tank.

As with the fix above, you’ll need to turn off your water supply line and drain your tank fully. There are more detailed instructions for this in the solution above.

2. Remove the tank.

You will need to take the tank off the toilet bowl. This is fairly simple. The tank will be bolted to the bowl.

You’ll find the heads of the bolts inside the tank.

Remove the washers and nuts from the bolts below the tank with your wrench. Pull the bolts out.

Then you can lift the tank up and put it down on your newspapers.

The gasket is on the flush valve. You’ll find it covering the valve nut. Slide the gasket out.

3. Replace the gasket.

After you remove the old gasket, you should slide the new gasket into its place. It’s important for this gasket to cover the whole valve nut.

Put a metal washer onto the bolts, then put rubber washers on top. This will prevent the toilet from becoming damaged.

Then put the bolts back from inside the bowl.

Any washers touching the toilet should be rubber rather than metal. Not only does this prevent damage, but it also creates a watertight seal to prevent tank bolt leakage.

4. Put the tank back and reconnect the water.

You’ll then lift the tank up and place it back onto the bolts. You should put a rubber washer onto the bolts to seal the interior of the tank.

Then put a metal washer on, and then tighten the bolts.

Double check the fill valve and toilet flapper. Sometimes the flapper needs to be adjusted, as it can shift out of place when the tank is initially moved.

Once the tank is in place, you’ll reconnect your water supply and flush the toilet several times. Check to make sure that there are no leaks.

Final Thoughts

A leaking toilet does not always need to be replaced entirely. Sometimes you just need to replace certain components that are worn down.

When the toilet leaks around the base, you can often solve the problem by replacing the seal. Similarly, you can fix leaks between the tank and bowl by replacing the gasket.

These two components tend to wear down over time.

If the toilet bowl itself is cracked, however, you will need to replace the toilet. You should shut off the water supply ASAP to prevent more leakage onto the floor.