How to Fix a Slow Draining Toilet: A DIY Guide

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Posted February 7, 2020

Many United States families aren’t aware that they spend an average of $330 more than they need to on their yearly sewer and water bill. If you make sure that your toilet and other plumbing systems operate properly, then you can go from spending $500 a year to $170 a year. Having a properly running plumbing system begins with identifying larger problems from smaller issues. For example, a slow draining toilet might not seem like a big deal, right? Wrong.

Toilets that aren’t flushing properly can be an indication of a larger problem that can cost you a lot of money.

If you can fix the problem by yourself before it becomes a serious issue, then you can money on plumbing expenses and your yearly utility bill.

In this guide, we’ll walk you through everything you need to know about fixing your slow draining toilet.

What Causes A Slow Draining Toilet?

Before we get into the different ways you can fix a slow flushing toilet, we should first go over the different causes. Once we know more about what is affecting the problem it should be much easier to figure out how to fix it.

1) Low Water Levels In Your Toilet Tank

The first thing you want to check when searching for the cause of slow drainage is the toilet tank. Remove the toilet tank lid and put it in a safe place. Then check your tanks fill level.

If the tank water looks lower than usual, then the issue is probably your toilet tank. When your toilet has a low water power it does not have much force behind its flush.

Thus, it leads to a slow flushing toilet. There can be a variety of reasons for low water levels in your tank. Most of the time it’s due to reasons beyond your control.

Maintenance can help, but toilet parts and systems will break down over time.

We often narrow it down to things like a broken fill tube, cracked tank or damaged fill valve — but it can come from any number of things. Check out these ten reasons why your house may have low water pressure.

2) Build-up or Blockage In The Drain

Every year one out of five Americans deal with a blocked drain. So, statistically, you’ll need to deal with it someday. Often a clogged toilet is obvious even to someone who knows nothing about plumbing.

But sometimes the problem isn’t so simple. The blockage can be partial or occur further down the system. System blockage is much harder to deal with than a simple clogged toilet.

So how do you know if you have drain build-up in your sewage system?

One good way you can check is with a gallon of water. Take the water and pour it into the toilet bowl. If the water immediately rises, then the issue is a clogged drain.

If the water sinks or stays the same, then the problem is more likely in the toilet tank. For a comprehensive guide, here is how to unclog a simple toilet.

3) Mineral or Sediment Build-up Along the Rim

If you find that your toilet bowl still drains properly — but slowly — then the issue may lie in the jet holes that surround the rim of the toilet bowl.

The build-up of sediments and minerals along the side of these holes can gradually reduce the water pressure released with each flush. In the next section, we’ll go into the different ways you can fix all of these problems.


Different Ways You Can Fix a Slow Draining Toilet

If you’re heart set on fixing the toilet by yourself, then these are some of the things you should consider during the repair process. We recommend taking a minute to refresh yourself on the parts of a toilet.

However, if you aren’t confident in your repair skills, then don’t feel bad about calling a professional plumber. Sometimes homeowners that don’t know what they’re doing when it comes to plumbing can cause more harm than good.

1) Remove the Damaged Fill Tube

The fill tube is a small, but an important component in the interior of the toilet tank. The tube is usually black and made of flexible rubber. It leads into a wide vertical tube known as the overflow tube.

Every time you flush the fill tube is responsible for transferring water from the tank to the bowl. Overtime the fill tube can become damage from usual wear-and-tear, during which it will eventually unclip.

When this happens the tank will fill with water which causes the valve to shut off. Thus, water slowly fills the bowl. You can fix this problem by inspecting the fill tube in your toilet tank.

If the tube appears in good condition but is disconnected, then you can simply attach it back onto the cylinder. However, if the tube appears damaged, then you will need to replace it.

2) Replace a Cracked Toilet Bowl

This problem is not as common as a damaged fill tube, but it can happen. Sometimes a crack can occur within the lower bowl of the toilet. This leak will cause water to gradually drip out.

You can identify it by puddles around the base of the toilet. The water in the toilet will also be noticeably replenished. Unfortunately, there is no simple fix for a cracked toilet bowl.

Any sealing agents you apply will likely be temporary at best. You will likely need to replace the whole toilet and install a new one. If you don’t feel comfortable installing a new toilet, then call your local plumber.

3) Dealing With a Blocked Sewer Line Vent

A sewer line vent is a pipe that runs out the bathroom wall and up to the roof of a house or building. The pipe’s job is to provide fresh air that will move water through the drainage system.

The sewer line vent also prevents toxic sewage gases from entering your home. Unfortunately, this plumbing component is susceptible to clogs.

What causes the clogs?

Anything from tree branches to dead squirrels — whatever can fit in the pipe. Depending on the severity of the clog the water level on your toilet can be affected since air simply isn’t getting through.

You can try and deal with the sewer line vent yourself by gaining access to your roof. See if anything external is blocking the pipe. If not, then shine a flashlight down the pipe.

You may see a clog if it’s not too far down. If you can reach it, then take a plumber’s snake and try to dislodge it. You will need to call a plumber if you cannot dislodge by yourself.

plunging slow draining toilet

4) Unclog The Toilet With a Plunger

Sometimes the reason for a slow flushing toilet is as simple as a clogged drain. Clogs can happen for a variety of reasons, but the most common answer is that someone flushed something they shouldn’t have.

If you find that the water level remains high for a minute or two after you flush, then there is likely something blocking the flow of water.

There are many different ways you can deal with this problem but we recommend one of two methods. The first method is with a plunger.

If you have a plunger, then insert it into the toilet. Make sure you wear gloves and have a good initial seal — things may get messy. Give the first plunge a gentle push.

Remember that the plunger is full of air, so a hard first plunge with send water spilling backward all over you. Once you finish the initial plunge, you can begin pushing in and out faster with the plunger.

Make sure you maintain the seal. Remember that plunging is a gradual process. A deep clog may take between fifteen and twenty minutes of steady plunging to loosen.

Stick with it and be patient. If it still seems hopeless, then try our second method of unclogging.

5) Unclog With a Combination of Drain Cleaner and Dishwashing Soap

The second method of unclogging a toilet involves drain cleaner, dishwashing soap, and hot water. First, pour one gallon of hot water into the toilet bowl. Allow it to sit and dislodge anything that may be clogging the drain.

Also, keep in mind that you shouldn’t pour hot water if you have an old porcelain toilet. Hot water may cause cracks in the bowl, which require replacement.

While the hot water sits in the bowl, find some toilet-approved drain clean. Pour a small amount into a bowl. Either flush it immediately or let it sit depending on the cleaner’s instructions.

Next, remove the lid on the toilet tank. Find the overflow pipe and pour one tablespoon of dishwashing soap into it. Give the dishwashing soap ten minutes to seep down the overflow pipe.

It will remove some calcium deposits during this time. After ten minutes you can flush the toilet. This should remove both the clog and some of the mineral deposits.

6) Replace the Damaged Fill Valve

A damaged fill valve can cause both a slow draining toilet and water wastage. Toilets that run after you flush them can make water utility bills soar. If your fill valve is the problem, then you first need to turn off your toilet’s water supply.

Take the tank lid off and flush the toilet so all the water drains out. Use a towel to mop up any remaining liquid. Next, unscrew the nut that connects the water hose to the bottom of the fill valve.

Pull the valve up from its base and insert the new fill valve into the hole left by the damaged model.

Use a wrench to secure the valve with a nut under the tank. Then, reattach the refill tube and the water supply hose. After this step, you can turn your water supply back on and test your toilet’s flushing capabilities.

7) Remove the Mineral Build-up Around the Jet Holes

If you find that your jet holes still have mineral buildup after the dish soap method, then you may need a more physical method of removing them. One way you can try involves a screwdriver and a mineral remover agent.

Apply a cleaner to the exterior of the jet holes and let it sit for a few minutes. Then, take a small screwdriver, or similar device, and physically scrape the mineral deposits away from the holes.

If you find that this process still doesn’t remove the build-up, then you will likely need to call a plumber to help.

slow draining toilet

How to Make Sure Your Toilet Doesn’t Break

Proper maintenance is key to making a toilet last long. Make sure you regularly check your toilet for signs of leaks and loose screws.

A simple leak caused by a malfunction gasket or wax ring can allow fluid and odor to come out of the toilet. It can also permanently damage the bathroom floor.

A wobbly base or an unsecured toilet seat can lead to cracking problems that will require a complete replacement of the toilet.

Regular cleaning of the toilet bowl and surround the jet holes can also greatly improve water flow. If you let it go too long without cleaning it, then the mineral deposits may become too much for you to handle.

Need Plumbing Help? Call Hiller Plumbing, Cooling, Heating & Electrical

Unfortunately, the DIY approach isn’t realistic for some types of plumbing problems. If you don’t feel comfortable enough to tackle your slow draining toilet on your own, then don’t feel bad.

There are tons of professionals out there that can help you get your plumbing system back up and running.

But what repair business can you trust?

Only companies like Hiller Plumbing, Cooling, Heating & Electrical provide technical expertise with family-owned values.

With a transparent pricing model and full-range of plumbing, HVAC and electrical service we can help you get your home back up and running. You can request your appointment today by visiting this link here.

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