Toilet Leaks When Flushed

If you have a leaky toilet, the first course of action you should take is to determine the cause of the leak. Toilets can leak from many places, but the most common culprits are the bowl gasket and the toilet wax ring. If the toilet is leaking inside the bowl, then the fault probably lies with the water tank.

Once you’ve determined the origins of the leak, you can start fixing things. Our article will provide you with the necessary know-how to become the in-house handyman you were always meant to be.

Find The Cause of The Leak

To start things off, flush the toilet and see what happens. If the leak is contained within the toilet bowl, then your issue stems from the water tank mechanism or the water valve. Replacing parts of the flushing mechanism like the flapper seat or the entire flushing mechanism will likely fix the issue. If replacing the flapper doesn’t work,  giving the water supply valve a makeover will fix the issue.

If water is flowing from the place where the toilet and water tank connect, then your issue lies with the bowl gasket. This gasket is made out of rubber and functions as a watertight seal between the toilet and the water tank.

If the water is leaking from the toilet’s base, then your issue lies with the wax ring. The wax ring is made from sticky wax, creating an airtight seal between the toilet bottom and the sewer line. These are inexpensive to replace but require you to dismantle your toilet.

Tricky Trickling Water

If you hear your toilet refilling itself after no one has flushed it, you may be facing a phantom flush. This is a toilet that suffers from a faulty flapper seat that causes it to overfill and leak water into the bowl. The solution is to drain the toilet tank and check the flapper seat. If the flapper is damaged, then you have to replace it. Here’s a helpful video that shows how to do that How to Replace a Toilet Flapper Valve – Plumbing Tips from Roto-Rooter.

If this doesn’t work, pay close attention to the noise of the toilet bowl. If you hear a hissing sound coming from the bowl, you should check if water runs into the overflow tube. Regular toilet bowls should fill up water about an inch below the overflow tube. If the overflow tube is damaged, your toilet will leak water into the bowl. You can adjust the float with a screwdriver for a temporary solution, but you will have to replace the whole valve assembly eventually.

Fix a Running Toilet…Fill Valve Replacement — by Home Repair Tutor

Bowl Gasket Diagnosis

If your toilet is leaking from where the toilet and the water tank are connected, the culprit is probably the bowl gasket. To check, you need to disconnect the water tank from the toilet first. This is a bit heavy, so we recommend you ask a neighbor or a friend to assist you with the dismantling.

A bowl gasket (also called a spud washer) is a rubber gasket that creates a watertight seal between the water tank and the toilet bowl. It is located outside of the flush valve, where the water leaves the tank and enters the toilet bowl. A worn-out bowl gasket causes your toilet to leak.

You need a brand new bowl gasket and a couple of tools at your disposal to install it. You should have an adjustable wrench, a flathead screwdriver, a putty knife, a sponge, a bucket for draining the sponge, a mini hacksaw for rusted bolts, a pair of safety gloves and goggles, and lastly, some old rags and newspapers to line your bathroom floor. If you aren’t familiar with these tools, calling a professional plumber might be the easier solution.

A step-by-step method for replacing your gasket bowl:

  • Turn off the toilet water supply and flush the tank to remove any water. You can use the sponge to soak up the remaining liquid.
  • Detach the housing unit that carries water from the water tank to the toilet.
  • Try to loosen the bolts that connect the toilet and the water tank. Use the hacksaw to saw them if they won’t give in. They are behind the toilet.
  • Lift the water tank with the help of another person and place it somewhere where it won’t be an obstacle.
  • Now that you’ve dismantled the water tank, you will see the gasket. Inspect the gasket to see whether it’s wet or cracked.
  • Remove the gasket but don’t throw it out if you haven’t purchased a new one. You will need it as a reference at the plumbing store if you can’t remember the model of your toilet rig.
  • If you have a new gasket, replace it with the old one and try to put everything back as it was. Try not to over-tighten the bolts as they can snap.

How to Replace Toilet Bolts and Gasket – Fix a Leaky Toilet

Wax Ring Shenanigans

If you’ve checked the bolts and replaced the bowl gasket, but the toilet is now leaking at the base, then your culprit is none other than the wax ring. Replacing the wax ring is tough, so get ready to do the heavy lifting. The wax ring is located under the toilet, and it connects the toilet’s base to the sewage pipe called a flange.  These wax rings usually last for many years, but hard water will deteriorate them quicker.

The wax ring is a piece of plastic or rubber molded with a thick wax on the outside. The ring creates an airtight seal between the flange and the toilet bowl base. It keeps water flowing between the toilet and the sewers and prevents sewage gasses from coming up and stinking up your house.

Changing the wax ring will probably solve the issue if your toilet is leaking at the base. A broken flange or loose toilet bolts may also cause similar leaks. If the toilet is wobbly, it can unseat the wax ring and create a leak. You can simply tighten the bolts with a wrench to see if that works

A step-by-step method for replacing the wax ring:

  • First, determine what’s going on with the bolts that keep the toilet connected to the floor. After that, proceed to the wax ring operation.
  • Turn off the water, as always.
  • Flush the tank and use the sponge to soak up any leftover water.
  • Disconnect the water supply hose from the toilet.
  • Unscrew the bolts on the sides of the toilet.
  • Firmly grab the toilet and gently move it from side to side in order to break the seal.
  • Lift the whole toilet, not the water tank, and place it on its side.
  • Scrape what’s left of the wax ring from the flange and the bottom of the toilet with your putty knife.
  • Place the toilet back into position and make sure that it stands evenly. If it doesn’t, scrape some more residue off the bottom.
  • Take your new wax ring and place it on the flange. Gently press down to get it positioned.
  • Place the whole toilet back on top of the flange and sit down on it. The wax seal will have to be squished down to create a seal.
  • Screw back the bolts and re-attach the water supply hose.

How to Replace Toilet Wax O-Rings : How to Fix Toilets

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