American Standard Toilet Leaking Between Tank and Bowl Fixed!

Regardless of its origin, a toilet leak is frustrating, wasteful, and, if left unresolved, increases the water bill. If you’ve owned an American Standard toilet, you know they are quality, reliable pieces, but why is my American Standard toilet leaking between tank and bowl, you ask?

A leak between the tank and bowl in an American Standard toilet stem from a faulty tank-to-bowl gasket, loose bolts, and worn-out bolts and washers. You may also be dealing with the tank-to-bowl gasket not compressing.

This issue may seem dire, but the best thing is you can DIY it and avoid hiring a professional.

New American Standard toilet leaking between tank and bowl

American Standard Toilet Leaking Between Tank And Bowl (Causes & Fixes)

If your American Standard toilet is leaking between the tank and the bowl, here are the causes and fixes:

 ProblemPossible CauseRecommended Fix
 1. Faulty tank-to-bowl gasketProlonged useReplace the gasket
 2. Loose toilet boltsFailure to tighten the bolts during installation.Tighten the bolts
 3. Worn-out toilet bolts and washersHard waterReplace the bolts and washers
 4. Failure to compress the tank-to-bowl gasketLoose boltsTighten the bolts

1. Faulty Tank-To-Bowl Gasket

A malfunctioned tank-to-bowl gasket is the leading cause of leaks between the tank and the bowl.

The gasket is the rubber fitting on the exterior of the flush valve where the toilet tank rests on the bowl. It aids in the formation of a watertight barrier as the water flows from the tank to the bowl.

When the gasket malfunctions or wears from long service, it will give up its seal, and you will see water seeping between the tank and the bowl. It is more visible when you flush the toilet.


  • Cut off the water supply to the tank by turning the shut-off valve clockwise.
  • Flush the toilet while pressing the lever down to drain all water from the tank.
  • Remove the tank cover and place it aside where no one will tamper with it.
  • Use a sponge or a piece of cloth to dry the water remaining in the tank. Do this until the tank is dry.
  • Disconnect the water supply hose. To do this efficiently, start loosening it by hand before proceeding with a wrench.
  • Place a bucket so water from the hose can pour into it.
  • Loosen the bolts inside the toilet bowl.
  • Lift the tank and place it on a flat surface or the toilet bowl.
  • Remove the malfunctioning gasket then install a new one.
  • Take the kit you bought and grab the rubber washer to install at the bottom of the tank, followed by the metal washer. These will seal the water in the toilet tank, while the series of nuts and washers will secure the toilet tank to the bowl.
  • Use a screwdriver and wrench to tighten the nuts. Nevertheless, be careful not to overtighten the bolts since you don’t want to incur extra costs due to damaged porcelain.
  • Install the tank back to its place and feed the washers under the toilet tank. Place the rubber washer first, followed by the metal washer, and finally, the nut.
  • Hand-tighten the nut first, then use a wrench to tighten it further.
  • Restore the water supply hose and turn the water supply back on.

NOTE: When buying a gasket, take the existing one to the store to get the perfect size to replace the faulty one.

How do I stop my American Standard toilet from leaking?

2. Loose Toilet Tank Bolts

Is your toilet tank wiggling? If it is, it signifies you have loose toilet tank bolts.

Toilet tank bolts apply pressure to the tank-to-bowl gasket to create a watertight seal, failing which your toilet will leak between the tank and the bowl. Corroded tank bolts that result from continuous contact with hard water will also have similar effects.


  • Begin by gripping the tank with both hands and try rocking it sideways.
  • If it wiggles, it implies the bolts are loose and not applying adequate pressure to the tank to bowl gasket, causing the leak.
  • Get an adjustable wrench and tighten the two nuts underneath the bowl. Do this alternatingly to ensure the tank remains level on top of the bowl.
  • Again, avoid overtightening the bolts to keep your porcelain intact; otherwise, it will crack, and you’ll need to replace the whole toilet.
  • If the toilet leaks between the tank and the bowl after this, replace the gasket and the bolts.

3. Failure To Compress The Tank And The Bowl Gasket

When toilet bolts fail to apply the required pressure on the gasket, the American Standard toilet will leak between the tank and the bowl. If it remains unsolved, it will inflate your water bills and create other problems, such as the toilet tank rocking.


  • Apply downward pressure to maintain the tank level while alternatingly tightening the bolts until the tank is steady.
  • Flush the toilet and check whether it is still leaking between the tank and the bolt. If it is, chances are the gasket is incompatible with your toilet system or worn.
  • If that is the case, replace the gasket.

4. Worn-Out Rubber Washers (And Toilet Tank Bolts)

In most settings, rubber washers go hand in hand with bolts, and an American Standard toilet is one of those applications. If they corrode or wear out, they will interfere with the seal, culminating in water leaking between the tank and the bowl and pool on your bathroom floor.

Thankfully, washers are affordable- so get them and save yourself from a leaking mess.


Remove The Worn-Out Washers and Tank Bolts

  • Cut off the water supply and flush the toilet to drain water in the tank.
  • Use a sponge to wipe all the water remaining in the tank.
  • Remove the toilet tank lid and place it aside, but away from the risk of falling and breaking.
  • Disconnect the water supply hose from the tank. Similarly to the gasket scenario, try to undo the connection between the hose and the tank by hand before getting a wrench.
  • As you do this, place a small bowl to catch water from the hose.
  • Check the two toilet tank bolt nuts beneath the bowl with your fingertips then loosen the nuts using a wrench and remove the tank.
  • If the bolts keep spinning but resist coming out, employ a long screwdriver to drive them out from within the tank and a wrench to undo the nut.
  • In other cases, the bolts will get severely rusted and will not budge. For such, use a hacksaw to cut them off.
  • The space could be too limited for a hacksaw; hence the reason plumbers recommend using a hacksaw blade.
  • Uninstall the toilet tank and place it on a level surface. You can place it on the bowl if you wish, but be cautious not to knock it off and break it.
  • Slip out the tank-to-bowl gasket and discard it. Next, extract the tank bolts from the tank using a wrench and screwdriver.

Insert The New Washers and Tank Bolts

  • Clean the tank and remove mineral deposits where you intend to install the replacement parts.
  • Install the washers and the tank bolts. As mentioned earlier, place the plastic washers (to be in contact with the porcelain) before installing the metal ones. It keeps the toilet tank from breaking as a result of overtightening.
  • Thread in the mounting nuts and washers on the bolts on the exterior of the tank and tighten them using a wrench and screwdriver. After that, slip in the tank-to-bowl gasket with the bolts securely in place.

Finishing Steps

  • Check that all of the tank parts are in good condition. If you displaced the flapper during the repair, reposition it.
  • Reconnect the water supply hose to the tank, open the shut-off valve and allow the tank to refill.
  • Flush the toilet multiple times as you check for leaks between the tank and the bowl.
Toilet leaking between tank and bowl when flushed


1. What Causes A Toilet To Leak Between The Tank And The Bowl?

The flapper failing to seat properly and establish a watertight seal against the valve seat is the most probable cause of a leaky toilet tank. It causes water from the tank to flow into the bowl and seep through the gasket.

2. Is There A Gasket Between Tank And Toilet Bowl?

The tank-to-bowl gasket’s function is to establish a leak-free barrier between the tank and the bowl. If you notice water leaking between the tank and the bowl, the gasket may be begging for replacement.

3. How Do I Know If My Toilet Tank Gasket Is Leaking?

Sprinkle a few drops of food coloring in the tank. If you notice colors in the bowl before flushing, you have a leaking problem.

4. When Should I Replace My Toilet Tank Gasket?

The longevity of the tank gasket depends on the water conditions. Experts suggest replacing it once every few years.

Final Thoughts On American Standard Toilet Leaking Between Tank And Bowl

You can trace American Standard toilet leaking between the tank and bowl to a faulty tank-to-bowl gasket, loose toilet tank bolts, worn-out washers, and failure to compress the tank and bowl gasket. Tighten what needs tightening and replace that which needs replacing.

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