Is your toilet gurgling, making odd noises, and not flushing properly? Those annoying gurgles and bubbles are a sign of a bigger problem. Don’t ignore a toilet that’s bubbling and won’t flush or you’ll risk expensive plumbing disasters down the road.
What Causes a Toilet to Bubble and Not Flush?
First, let’s quickly cover what causes a toilet to make bubbles and gurgling noises when flushed.
These bubbling toilet noises are caused by air and gases escaping from your drain or sewer line back up through the toilet. The air bubbles and gurgles happen when there is some type of partial blockage deeper in your plumbing drain system.
Some common causes include:
- A clogged drain or sewer line
- A blocked vent stack
- A clog or restriction in the main sewer line
- Build up in pipes causing air pressure imbalances
These types of obstructions allow sewer gases to come back up the toilet rather than flowing out properly. The bubbles and gurgling noises happen when the air escapes through the water in the toilet bowl.
Why You Shouldn’t Ignore a Bubbling Toilet
It’s very important not to ignore a toilet that bubbles and gurgles when flushed. At best, it’s a sign of a partial clog or blockage that will get worse over time. At worst, it could indicate a major backup or plumbing failure is imminent if not addressed quickly.
Other problems that can arise if a bubbling toilet is ignored include:
- Raw sewage back-ups
- Toilet overflows and flooding
- Sink and bathtub drains start gurgling as well
- Unhealthy sewer gases enter the home
- Complete sewage line failure requiring expensive repairs
Catching a problem early based on gurgling noises can prevent much larger plumbing headaches. While the bubbling can be an annoyance, take it as a warning sign to investigate and fix the issue promptly.
Method 1: Plunge the Toilet
The first easy DIY method to try with a toilet that’s bubbling is a simple plunge. Often some type of object or debris has clogged the toilet drain enough to cause bubbles, and a vigorous plunging can dislodge the blockage.
Follow these steps:
- Shut off the water supply valve behind the toilet.
- Press the plunger firmly over the drain to form a tight seal.
- Quickly push the plunger up and down 15-20 times in a row with vigorous force.
- Flush the toilet to see if plunging cleared the clog.
- Repeat steps 2-4 if needed until water flushes normally.
Some tips for getting a more effective plunge include:
- Use a large plunger with a wide bell end designed for toilets.
- Fill the toilet bowl with a few inches of water before plunging if needed.
- Create a very tight seal around the drain to forcefully move the blockage.
- Target different areas of the drain and push down with extra force.
When to Use a Closet Auger
If plunging fails to fix the bubbling toilet, the next step is to use a toilet auger or closet snake. This long flexible metal cable feeds down into the toilet drain and physically hooks and pulls up the obstruction.
A closet auger works better than a plunger for:
- Removing objects like toys or wipes that are caught in the trap.
- Breaking apart and pulling out masses of toilet paper or debris.
- Dislodging partial blockages further down the pipe.
Be sure to slowly feed the auger down the toilet and gently pull back to avoid scratching the porcelain. A closet auger paired with a plunger often resolves many simple toilet clogs.
Method 2: Check for Tank Issues
If plunging and snaking the toilet drain doesn’t eliminate the bubbling, next check for problems inside the toilet tank causing airflow issues.
Things to inspect include:
- Flapper valve – If worn out it may not seal well allowing water/air leaks.
- Fill valve – If set too high it will overflow with air bubbles.
- Overflow tube – If cracked, it can release extra air into the bowl.
Carefully remove the toilet tank lid and set it aside. Flush the toilet and observe if any of these parts appear faulty while the tank refills.
To adjust the tank water level, simply raise or lower the float along the fill valve shaft. The correct level is about 1 inch below the overflow tube opening.
If you discover any broken or dysfunctional toilet tank parts, repair or replace them as needed to prevent excess air from entering the bowl.
Bubbling from Excess Tank Air
Even if all the tank parts are functioning properly, there may be too much air in the tank causing bubbles. Air can get trapped in the tank if the refill rate is too fast after flushing.
Some steps to eliminate excess air include:
- Adjusting the tank water level as mentioned above
- Partially closing the water supply valve to refill more slowly
- Installing an adjustable fill valve for more control
- Checking that the water supply line is not leaking air
Proper tank fill settings matched with an airtight tank should prevent air from burping up into the bowl and causing gurgling noises.
Method 3: Clear the Main Drain Line
If the toilet bubbles even after plunging and inspecting the tank, chances are there is a larger obstruction in the main sewer drain line.
Signs that point to a main drain clog include:
- Water in other drains (sink, tub) drains very slowly
- Main cleanout cap outside bubbles when toilet flushes
- Sewer gas smell coming from bathroom drains
- Toilet the only fixture exhibiting issues
There are a couple ways to clear out the main drain line and sewer:
Drain Auger
For accessible blockages, use a drain auger (sometimes called a drain snake). Feed the rotating auger down the main drain line cleanout to break up and hook debris.
Slowly crank the handle as you push the snake deeper through the pipes. Retrieve and empty the auger to remove any sludge pulled back.
Chemical Drain Cleaners
For tougher clogs, you may need a powerful chemical drain cleaner. Only use these with extreme caution by following all label directions.
Pour the drain cleaner product down the toilet drain and let it sit for the recommended time to dissolve blockages. Then flush with plenty of hot water.
Avoid using these too frequently, as they can damage pipes. Seek professional help if chemical cleaners fail to clear chronic clogged drains.
Warning: Only Attempt if Drain Accessible
Only try snaking or using drain cleaners if you can directly access the main cleanout drain. If pipes are inaccessible, call a professional rather than dumping chemicals down fixtures.
When to Call a Professional Plumber
While the above methods may resolve a toilet that bubbles and won’t flush properly, don’t take chances with plumbing problems.
Call a professional plumber promptly if:
- DIY efforts don’t solve the bubbling and flushing issues
- You suspect the vent stack or sewer gas leaks
- The main sewer line may be severely clogged
- Your home has a septic tank that may be backing up
- You are unable to access the main drain line cleanout
- You want to prevent flooding disasters and unnecessary risks
A skilled plumber has the equipment to diagnose issues like blockages, collapsed pipes, septic problems, and airflow restrictions. They can also safely handle chemical drain cleaners.
Don’t play guessing games with persistent bubbling and gurgling sounds. Call the experts to examine your drains and prevent severe backups or overflows requiring costly repairs.
We hope this overview gives you a place to start in troubleshooting a toilet that gurgles and bubbles. Plunging, adjusting the tank, and clearing the main drain line are three DIY methods you can attempt before calling a plumber.
However, don’t wait until you have a major plumbing emergency. Sewer gases escaping back up the toilet is never normal. Strange bubbling and gurgling noises always warrant immediate attention.
By acting quickly, you can potentially fix minor toilet clogs yourself and avoid extensive plumbing repairs down the road. But when in doubt, call a professional to ensure the problem is properly diagnosed and corrected.
Save yourself headaches and prevent a gross and costly sewer backup or toilet overflow. If you hear gurgling coming from your toilet, take action right away before it’s too late!
1. Overflowing Water Tank:
Another reason for a toilet that bubbles and won’t flush could be due to an overflowing water tank. If the water level in the tank is too high, it could lead to air becoming trapped in the tank, causing bubbles in the bowl. This could be due to a faulty fill valve or a damaged float. To fix this, you can adjust the float or replace the fill valve.
2. Low Water Pressure:
Low water pressure in your home could also cause a toilet to bubble and not flush properly. This could be due to a problem with the water supply, or it could be due to a blockage in the main water line. If the water pressure is consistently low, it’s best to call a professional plumber to diagnose and fix the issue.
3. Old or Damaged Pipes:
Old or damaged pipes could also cause a toilet to bubble and not flush properly. Over time, pipes can become corroded or cracked, causing blockages and negative air pressure. If you suspect this is the case, it’s best to have a professional plumber inspect the pipes and recommend any necessary repairs.
