Toilet Won’t Flush Well All the Way and It’s Not Clogged-Causes& Fixes

Ndesho ThomasLast Updated: February 28, 2024

It can be quite a frustrating encounter when your toilet is either flushing partially, or not flushing at all. If not fixed in time, bad smell around your house, overflowing and build-up of nasty clogs are some of the issues that will follow up, of course, worsening the situation.

The most common reasons your toilet won’t flush when not clogged include too little water and dirt in the tank, worn-out or malfunctioning tank components (flapper, flush handle or button) and poorly designed piping setup. Blockages and clogs in the toilet drain pipes, inlet holes in your bowl and vents can also prevent water and waste from draining properly.

The following is detailed discussion of the issues and ways to resolve them. Some of the issues can be easily fixed while others will require services of a licensed plumber.

As always, when carrying out any repairs or fixes, protect yourself from the harm that may come from the tools, parts of the structure you’re fixing, and contamination from dirt and germs. For this reason, ensure there is enough ventilation, have a pair of rubber gloves, a mask, and other protective gear

Contents show

My Toilet won’t Flush and it’s NOT Clogged

Toilet flushing issues that do not involve clogs usually revolve around the tank and its components. It has a lot to do with, the amount of water in the tank, which is determined by the condition of the tank, the float ball, the flapper, flush button/handle among other settings.

Condition of the Toilet Tank (Leaks/Cracks)

A broken tank will result in leakages. A leakage means the water in the tank won’t be enough for a proper and stronger flush.

The causes of a leaky toilet include;

Misaligned or worn-out tank-to-bowl gasket (spud washer)
Deteriorated or loose rubber washers at the bolts
Worn-out or poorly-fitted fill-valve
General wear and tear due to aging
Crack in the overflow tube

This is most obvious sign of a tank leakage is flooding on the floor. Other signs include;

Toilet runs intermittenly
Toilet runs for longer than the usual amount of time/ or it runs but the tank does but the tank won’t fill
You hear noises from the toilet when it’s not in use
An abnormal rise in your water bill

Solution

The easiest way to fix a leaky or broken tank is to replace it especially old and worn-out. The other specific solution is to adjust the fill valve, tighten the loose bolts and align/replace the gasket.

Incorrect Tank Water Level Settings-Faulty Float Ball

In the toilet tank there is a level marked for which the water has to reach to provide a good flush. If this level isn’t attained, there will be too little water in the toilet tank such that when you flush it the waste won’t be washed away.

The amount of water in the tank is determined by how you set the float ball. There are two ways to adjust a float ball to provide the needed amount of water;

Method one; simply bend the stem holding the float ball to the rest of the toilet upwards.

The other method entails turning the screw at the end of the float ball arm in a clockwise direction to raise it upwards. This method is mostly used for toilet tanks with floating cup ballcocks.

For both solutions, you might want to repeat and readjust the float ball level to find the right level of water in the tank.

For the toilet to flush successfully, it needs a certain amount of water delivered at once to push through the P-valve to the drainpipe. If the right amount of water is delivered but not at once, it won’t flush correctly. If little water is delivered at once, it still won’t flush as needed.

The reason your toilet tank might not have enough water include a faulty float ball, poor settings on the water level in the toilet tank and dirt in the toilet tank. The following are fixes for these tank issues

Dirt in the Toilet tank

While quite uncommon, dirt in the toilet tank reduces the amount of space to be occupied by water. Such dirt be the floating type which takes up space at the top of the tank, or mud and other dirt that sinks to the bottom of the tank.

The likelihood for a tank that stays closed is muddy water whose dirt settles to the bottom of the tank taking up space that would otherwise be used by the water. If the tank is left open, children and pets can dump toys, sticks and other objects into the toilet tank with the result that there will be too little water for a proper flush.Solution

Depending on the type of dirt in the toilet tank, you should get it out accordingly. If there is mud at the bottom of the toilet tank, simply stir it up then flush it several times until you’re rid of it. You can also cut off the supply from the mains then give the tank a thorough wash. For solid objects, simply take them out and keep the tank closed afterwards.

Dirt in Toilet Tank; Rust, mold and mud — Toilet Tank Dirt

Further Reading: How to Clean a Toilet Tank- DIY Hacks & Best Cleaners

A malfunctioning Flapper

The flapper of your toilet is the valve between the toilet tank and the pipe leading to the toilet bowl. It has the simple yet important role of allowing water to fill the tank by closing the opening to the toilet bowl, and allowing water to flow to the toilet bowl when flushing the toilet.

Toilet flapper — Toilet flush valve seal/Flapper

This piece of plastic or rubber can become damaged preventing the toilet tank from filling up completely. When the flapper has holes, it can’t close completely or the chain linking it to the flushing handle is stuck, water will leak into the toilet bowl instead of filling up the tank. When you flush the toilet, the tank won’t have enough water to fill up the toilet bowl and wash away the wastes.

Solution

The solution to this issue is often replacing the toilet flapper in totality. If it has holes or damaged in any way, you will need a new one. If the chain is broken or tangled, fix it as needed. A broken chain may require a new one while a tangled one will do with a simple un-entanglement.

A Poor Design of the Toilet Drain Pipe

The design of toilet drain pipes has to adhere to some rules which are put in place to obey the laws of physics. For example, given that there’s no pump drawing or pushing wastes into the drainpipe, gravity needs to be utilized. For this reason, all drainpipes need to have a sloping design to allow waste to flow easily to the sewage tank.

Without such a slope, the waste won’t flow to the drain and will instead pile up leading to a clog in the drainpipe.

At the same time, the drainpipe needs to be of a certain size for its contents to flow without a hinderance. In most areas, there is a law dictating how small a drainpipe can be with the focus being on preventing clogs caused by pressure imbalances and solid objects.

If the drainpipe is too small in size, flushing won’t be easy as it’ll easily get overwhelmed with the volume of water that flows into it.

Solution

The solution for this one needs a professional plumber to dig up the drainpipe and most of the plumbing system to lay it afresh. This is extensive work which we only recommend that it be handled by a professional. Mistakes made here can lead to serious consequences.

Poor Flushing Procedure

At times, it’s not the toilet but us the users that are the problem. The toilet’s flushing procedure is created in a way that allows a large amount of water from the toilet tank at once to flow to the toilet bowl. As noted before, if the amount is right but it flows slowly to the bow, flushing won’t be effective.

Some users don’t press the flush handle or flush button at once and instead do it slowly. This may only allow a small amount of water to leave the cistern and may lead to an inefficient way of flushing.

Solution

The solution is to flush the toilet by giving the flush button or handle one reasonably quick press. This opens up the flapper wide enough for the water to rush from the tank into toilet bowl effectively flushing the wastes away.

Toilet Won’t Flush Clogged

As mentioned earlier, apart from the tank issues, the other reason your toilet won’t flush strongly all the way is clogs which block the flow of waste and water. The clogs mostly occur in the drain pipes, toilet bowl inlets and vents.

A clog anywhere in your plumbing system, will stop water from completely flushing down the toilet.

Dealing with clog will depend where it is and how severe it is. It is very easy to remove light clogs especially those within the bowl. For severe clogs deep down the drain, we a recommend a professional plumber.

Check the following articles for DIY Toilet Unclogging Instructions

Light Clogs

Severe Clogs

Will a Toilet Eventually Unclog Itself? What Happens if You Leave it Clogged?

Clogged Bowl Inlet Holes

Underneath the toilet bowl is a series of holes through which water flows out from into the bowl. The purpose of having a series of holes instead of one single outlet helps spread out the water thus covering the whole toilet bowl at once.

These holes can get clogged up either by mineral deposits or dirt in the water. You can look at them using a mirror held facing the underside of the toilet bowl’s rim.

Solution

To unclog the inlet holes, you need to follow the procedure below:

Heat about 12 ounces of white vinegar to at least 120 degrees Celsius.
Remove the lid from the toilet tank.
Pour the hot vinegar into the overflow tube of the toilet tank.
Let the white vinegar stay in the overflow tube for at least an hour or even overnight without flushing the toilet.
Use a piece of wire to clear the inlet holes then flush the toilet to clear away the remaining dirt.

Another solution is simply pouring muriatic acid into the overflow tube, waiting for a while then flushing the toilet.

Further Reading: How to Clean & Unclog Toilet Siphon Jets for a Stronger Flush

Poor Venting and Blocked Vents

Venting toilets and other plumbing units in the home helps equalize pressure between the pipes and the surrounding air. This helps gases and liquids to flow freely in the pipes and other connections made on the plumbing system.

If the toilet isn’t vented properly, the imbalance in pressure will not permeate easy flushing. You might also observe bubbles in the toilet, bad odors indoors and other unpleasant experiences.

Solution

The solution to improper toilet venting is simply to inspect your venting system and fix where possible. Follow the resources below details

While some of these approaches can be done as DIY projects, others will require the input of an expert for the best results.

Why Toilet won’t Flush Strongly (Weak Flush)

There are times when your toilet flushes but water drains slowly or fails to drain everything in the bowl. Various issues may cause this. Some of them include:

Dirt and mineral deposits might be blocking water flowing under the rim of your bowl. Partial blockage often results in a slow and weak flush.
The flapper might also fail to open completely. When it fails to open, little water is released thus creating a weak flush.
You might have clogged or blocked plumbing vents.
Old and low flow toilets always have poor flushing power. The low-pressure results in poor flushing.
You might be experiencing a sewer line problem. There might be plants, tree roots or any other dirt that develop inside the sewer line thus creating a backup. There might also be a partial clog in the sewer line that has never been removed when plunging. This causes poor flush.

Toilet not Flushing at all

According to some pro plumbers, the toilet might completely fail to flush due to the following reasons:

Full sewer tanks thus creating a backup. This might cause clogging in the sewer line thus flushing proves impossible.
The bowl might be clogged by materials such as toys, tampons, wet wipes, dead plants, and too much toilet paper.
In some cases, the flapper is either bent or warped.
There might be something stuck in the trap. The trap is S-shaped and separates the drainage line from your toilet. Tiny materials such as toothbrushes can easily get stuck in the trap and with successive flushing, more debris gets wrapped on the material eventually causing clogging.
Dirt or other objects in the tank. They might have fallen inside accidentally or your kid might have placed them there. These materials might hold on to the flapper and prevent it from flushing.
Old or worn-out Flapper and Fill Valve
Insufficient water supply. You might have turned off the water supply through the valve that runs between the toilet and the wall. The water level in the tank needs to be an inch below the top of the overflow tube.
The flush handle/button might be not be functioning well resulting in no flush.

Further Reading;