Are you searching for a solution to a “garbage disposal leaking from bottom?” If so, you’re in the right place. Read on to learn all you need to know and when it’s the right time to call a pro.
Why Your Garbage Disposal Is Leaking From the Bottom
In this guide, we’ll show you:
- How to diagnose the reason your garbage disposal is leaking
- DIY fixes you can try for each cause
- When to call a professional for help
If you’ve noticed your garbage disposal leaking from the bottom, you should act quickly. Dripping water under your sink will cause severe water damage in a short amount of time.
What This Article Covers
Since time is of the essence, calling a plumber is the best course of action. If your plumber can’t make it out right away, read our guide to find out:
- How to diagnose where the leak is coming from
- How to try to fix the leak on your own
- And when your best option is calling a professional instead
It may look like your garbage disposal is leaking from the bottom, but remember that water flows downward. The leak might be originating from the top or side of the garbage disposal instead.
There are limited problems that could be the reason behind your garbage disposal leaking from the bottom. The good news is that it’s pretty easy to pinpoint the problem.
The bad news is that if the disposal really is leaking from the bottom, you may need to replace it. It could be something as simple as retightening connections or using plumber’s putty to reseal parts.
Let’s start with diagnosing the reasons that can cause garbage disposal leaking from the bottom.
Diagnose the Garbage Disposal Leak
Before you begin diagnosing the garbage disposal leak, make sure you do two things. First, and most importantly, turn off the garbage disposal and unplug it before doing any diagnostics.
As an electrical device near water, you can receive a nasty shock if it’s on while you examine and touch it. Second, go ahead and place a small wastebasket or bucket under the leak to catch the dripping water.
Find the Leak
To pinpoint where the leak is coming from, grab a flashlight and dry the disposal off with a paper towel. Shine the light all around the disposal to see if you determine where water first starts leaking out.
If it’s impossible to tell, or if it seems that water may be leaking from multiple spots, try the following technique with food coloring.
- Turn off and unplug the garbage disposal unit.
- Ensure a wastebasket or bucket is under the disposal to catch any water.
- Turn on the water in the sink, plug it, and fill until it’s nearly half full.
- Add several drops of bright food coloring to the water in the sink.
- Watch under the sink with your flashlight to see where the leaks are appearing.
You may or may not be able to pinpoint where the leak is coming from with these two methods, but if you can narrow it down, you can save some time.
- If the water is actually leaking from the top and flowing down to the bottom, check the section Sink Flange Seal.
- If it looks like the water is actually leaking from the side of the disposal and flowing down to the bottom, check the section titled Garbage Disposal Drain Lines.
- If it still appears it’s leaking from the bottom as you suspected, read the section Garbage Disposal Internal Seal.
- If it looks like the water is leaking from the body of the garbage disposal itself, read the section Cracks on Garbage Disposal.
We’ve tried to make the most complete guide on the web, and if we can’t solve the problem here, it’s best to call a plumber. Do so with the form below!
Garbage Disposal Internal Seal
Leak Origin: Starts from the bottom of your garbage disposal
If you see the leak is originating from the bottom of your garbage disposal, the most likely culprit is the garbage disposal itself. Garbage disposals don’t last forever.
In fact, most last anywhere from 10 to 15 years under normal conditions. Inside your garbage disposal, several internal seals experience wear and tear over the years.
When one or more of those seals is worn out, you will see the telltale leak from the bottom of the garbage disposal. It won’t get better, and it can’t be fixed with plumber’s putty.
The Fix: If your garbage disposal’s internal seal is worn to the point of causing a leak, you have two options.
The first option is purchasing a replacement garbage disposal. Expect to pay $250 to $400 for a new disposal and to have it professionally installed.
The second option is calling the manufacturer if your garbage disposal is still under warranty. Your warranty period will vary by the manufacturer. You may be able to see a small tag on your disposal with the serial number.
Contacting the manufacturer can help you decode the serial number to determine the date of manufacture and how much time is left on the warranty, if any.
Sink Flange Seal
Leak Origin: The leak appears to come from the top and drip down to the bottom
Your garbage disposal is installed in your sink and connected with a sink flange and plumber’s putty. Plumber’s putty that seals the sink flange to the garbage disposal wears or corrodes over the years.
As a result, water makes its way through and results in a leak. The flange can also be shifted out of place by being bumped (especially if you’ve been doing other plumbing work under the sink).
This kind of leak will look like it’s dripping from the bottom, but it’s actually starting at the top of the garbage disposal where the flange connects to it.
The Fix: If the sink flange seal has gone bad, you may be able to stop the leak by getting some plumber’s putty ($2 to $4) from your local hardware store, depending on the way your sink flange is installed (screws or putty).
If it’s installed with putty, the garbage disposal will need to be removed, the old plumber’s putty cleaned off, and the sink flange resealed with fresh plumber’s putty.
This is a moderately tricky job that requires removing drain hoses, pulling the entire disposal unit out, ensuring the seal is flat, and reconnecting everything once complete.
If your sink flange is attached with screws, you’ll need to call a plumber to take it out and replace it.
Garbage Disposal Drain Lines
Leak Origin: The leak appears first from the side, but drips down to the bottom of the garbage disposal
If you have a dishwasher, its drain lines connect to your garbage disposal side under the sink. There will be two drain lines connected to your garbage disposal.
The small drain line is the dishwasher drain line. The dirty water from your dishwasher travels through this pipe to drain into the disposal.
The larger drain line is what connects your garbage disposal to your sewer. When you grind waste in the disposal, it (along with any water from the sink) is carried into the sewer through this drain line.
Where these two drain lines connect could be the culprit behind your leak. If you can see that the leak seems to originate from the sides of your garbage disposal, then drip down to the bottom, this is the likely issue.
The Fix: It’s possible that the dishwasher drain line (the smaller one) isn’t clamped tightly enough to the garbage disposal, resulting in a leak.
If that’s the case, you should be able to tighten the hose clamp around the smaller drain line with a screwdriver. Dry the area with a paper towel and watch to see if there is any further leakage.
The main drain line (the larger one) could also be the problem. It should be connected with screws. A rubber gasket is inside it. If the screws are loose, you can tighten them to stop the leak.
If tightening the screws doesn’t stop the leak, the rubber gasket is probably worn. It will need to be replaced.
Cracks on Garbage Disposal
Leak Origin: From tiny or visible cracks on the disposal that may flow down and appear to come from the bottom
Another possible reason for a garbage disposal leaking from the bottom is that they body could be cracked. Use a flashlight to examine your garbage disposal closely.
Dry it off with a paper towel and watch for drops of water or wet spots to show on the garbage disposal body. If you find any cracks or wet spots that form directly on the body, there is only one option.
The Fix: Cracks in your garbage disposal mean it will likely need to be replaced. Garbage disposals last anywhere from 10 to 15 years and can sustain damage during that time from jostling from retrieving objects stored under the sink.
When to Call a Professional
As homeowners, we love to tackle jobs that we feel confident about doing. There’s no better feeling than tightening a connection and single-handedly stopping a leak!
However, when it comes to plumbing jobs, there’s a limit to what projects are suitable for DIY. Inexperienced handling of plumbing pipes and parts can cause more damage than the original leak.
In many cases, you’ll need to call a professional for a plumbing job. Leaky garbage disposals usually require a plumber’s expertise. Here are the scenarios that call for a professional to do the job.
Worn Internal Seals
If the leak is coming from the bottom due to a worn internal seal, your garbage disposal needs to be replaced entirely. It’s a pretty complicated job involving several plumbing connections.
And most DIYers won’t want to mess with them. Call a plumber to replace a garbage disposal if it’s leaking from the bottom, and you’ve had it for five years or more.
Worn Flange Seals
If the leak is coming from a worn sink flange seal, you need to remove drain hoses and the entire garbage disposal unit. You’d have to apply the seal carefully to ensure it’s flat and allows the sink flange to fit flush with your sink.
Then, you’d have to reconnect everything correctly to ensure it didn’t create a larger leak. It’s best to call a plumber if the leak is coming from your sink flange seal.
Worn Rubber Gasket
If the leak is due to a worn rubber gasket in your garbage disposal’s main drain line, you’ll need to call a plumber. They will be able to determine the properly sized gasket to install and ensure the drain line doesn’t continue leaking.
If the leak is due to cracks in the garbage disposal body, it will need to be replaced entirely. This job requires a professional plumber’s knowledge and skill, who can ensure everything is correctly installed and leak-free.
Still Have a “Garbage Disposal Leaking From Bottom?”
If you still have a garbage disposal leaking from the bottom, it’s best to call a plumber. You can try to fix it yourself, but water damage is expensive to fix.
Unless you’re a skilled handyman, it’s best to leave this to the pros. Fortunately for you, our we make it easy to connect with a pro. Simply click the link below to use the Networx system to find a local trusted and vetted plumber.