Toilet Flapper Closing Too Soon? Here’s How to Fix That

A house is filled with a never-ending list of things that need to be cared for. While most major maintenance issues always take priority, some of the more annoying ones can end up being quite problematic if left unattended for extended periods. One of the significant areas where the little maintenance details can often be overlooked is plumbing, especially in the bathroom.

Toilet problems specifically can spell trouble in this regard. Most problems fall into two categories:

  • Subtle, annoying issues that linger or get worse slowly
  • Immediate catastrophes that need a plumber right away

There’s not really much middle ground, unfortunately. Flapper problems, thankfully, fall into the first category.

If your flapper is closing too soon, it usually revolves around a timing issue. Depending on the specific problem, it can be fixed by adjusting the ball float, cleaning the flapper of build-up, or replacing the flapper itself (in cases of product defect).

Why Do Flappers Not Close Properly?

The flap that covers the water drain that empties water into the toilet is also known as a flapper. It’s a crucial piece of the inner workings of a toilet because it opens to release the water into the bowl when you flush, and closes to stop the flow and refill the tank for the next flush.

While most homeowners think that water leaks around a tub are the only significant worry in a bathroom, toilet leaks can cause homeowners some big financial headaches if left unattended. They could cause high water bills, or form/worsen cracks in the toilet!

One of the major concerns arises when the toilet tank flap does not close properly. There are various reasons this can occur. The aging of the parts is often the most common cause. This is especially true with older toilets that are prone to rust, but even when most parts are plastic, corrosion can still occur with some smaller parts.

When the flap does not close properly, it can cause a significant problem with toilet flushing, back-up, and substantial excess water use.

Causes of Toilet Flapper Malfunctions

Flapper Not Closing Completely

When a flap fails to close all the way, it can cause the toilet to not flush thoroughly. In addition, it can cause a significant amount of excess water usage as the tank can continuously fill with water even at times when the toilet is not in use. When the flap fails to seal, water will leak into the toilet bowl, and the system will keep refilling the tank whenever the water gets too low.

For homeowners who have hard or soft water or tend to have water particle build-up, it may be that the flapper and flush valve simply need to be cleaned to ensure it closes properly. If particle build-up sets in around the seal, it can cause a malfunction in closing.

Improper Positioning

There are occasions when the ball float and the arm are not appropriately positioned. This can possibly be resolved with a simple raising or lowering of the arm tension.

The water level can be adjusted to help the flapper close when the proper water level has filled the tank by bending the float arm slightly. Bending the arm slightly upwards will increase the water level in the tank, and bending the float arm slightly downwards will lower the water level required to fill the tank. It’s essential to be cautious to not over bend the arm, or it could cause significant malfunction creating a need to replace the entire kit.


If the valve doesn’t seem to fill the tank properly, it is likely caused by a float malfunction or the chain getting tangled. This may require continuous adjustments in order to ensure it works properly. It also could be the beginning of a malfunction that requires a kit replacement.

If the toilet tank kit is relatively new and it is still having problems closing correctly, there may be a malfunction in the flap itself and may not be properly sealing. Flappers are fairly inexpensive items, so it is usually a worthwhile investment to replace them if there appears to be a defect in the seal.

For homeowners who are not mechanically savvy, using a plumber to replace the toilet tank kit (vs. just a chain or ball) is recommended since the process requires a bit of technical ability. Improper installation can cause further headaches down the road and lead to additional water loss, leaks, back-ups, and poor functioning.

When a toilet tank flap closes too soon, it usually results in insufficient water amounts in the tank. If this occurs, the toilet will often need multiple flushes to ensure the toilet bowl empties properly.

Toilet tank flaps that close too soon are one of the most common malfunctions of a toilet tank kit. One of the reasons this can occur is because of a malfunction in the float arm or in the chain. If the float arm is not installed properly, the water level may be set so that it closes the flap before the tank is filled with water.

Depending on the exact problem, you will often be able to fix the issue yourself. However, professional plumbers are very familiar with the installation of water tank kits and can install a new kit and have a toilet up and running within a short time with minimal downtime.

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