How to Fix a Leaky Garbage Disposal

Even the most trustworthy garbage disposal will develop a leak from time to time; however, just because your food waste disposer has developed a leak does not necessarily mean that it needs to be replaced. Doing a little bit of investigating and troubleshooting before deciding to run out and buy a new garbage disposal can mean the difference between spending $10.00 for a replacement and $100.00+ to replace the entire unit.

Here is a look at the most common reasons for garbage disposal leaks and how to repair them:

Leaking Flange

The uppermost portion of a garbage disposal is referred to as the sink flange. It is the point where the sink drain and garbage disposal meet one another. There are multiple reasons why it might develop a leak. For example, the mounting bolts that secure the flange in place might not be tight enough. In total, there are three mounting bolts.

Alternately, the plumber’s putty might have failed. To replace the putty, the retaining bolts must be loosened. After a gap has formed, new putty must be forced between the pipe and flange. The bolts should then be retightened to secure the putty into place.

Home Depot’s website offers an excellent step by step guide on how to repair a leaking sink flange, which you can find here.

Loose Seals or Pipes

The bulk of a food waste disposer system, which includes the seals and pipes, is located beneath the kitchen sink. Most homeowners use this space to store various items, and it is not uncommon for people to bump or jar the disposal’s pipes when reaching for an item that is in close proximity. If the pipes are struck hard enough, the pipes can shift so that they are no longer sitting properly. Retaining bolts can become loose. Pipes may move, and seals can shift into an awkward position.

If your garbage disposal develops a leak, check to ensure that nothing has been knocked out of place. Look to see where the leak has developed, and then tighten the retaining bolts. If the leaking still continues to occur, then you will more than likely need to replace the sealing ring or the plumber’s putty.

Leaking Gasket

Take a moment to locate the source of your garbage disposal’s leak. If the leak has developed at the top rim where the rubber seal is mounted to the flange, then the potential cause of your leak could be the garbage disposal’s oversized rubber gasket.

When rubber gaskets age, they can develop leaks. The gasket can dry up, crack, and leak when it is repeatedly exposed to long periods of disuse where no water is present in the drain. Should an older garbage disposal be removed and then placed back, it will require a new rubber gasket to again achieve a watertight seal. Moreover, if a gasket is not evenly locked on all three sides, then it will develop a leak.

The good news is that a leaking gasket can be easily replaced. Most home improvement or local hardware stores will carry them, and they are usually inexpensive. However, depending on the particular model of your garbage disposal, it may require a specially fitted rubber gasket. To ensure that you get the right gasket the first time, write down your garbage disposal’s model number, take it to the store, and ask an employee to match it up for you.

To replace a rubber gasket, your first step will be to unplug the cord to the garbage disposal and then disconnect the drain. If you have a dishwasher installed in your kitchen, the dishwasher drain hose will need to be disconnected from the disposer. With the cord and appropriate drains removed, you can now grasp the sides of the mounting nut and twist it in a counter clockwise motion, which unlocks the garbage disposal. The waste disposer should then drop right down.

Place the garbage disposal on a wide, clean work surface and locate the rubber gasket. The old gasket should be peeled off, and the new gasket should be mounted in the same spot. Take extra care to make sure that it sits flat and that it pops into the lip. Now you are ready to re-install your garbage disposal. Plug the cord back in reconnect each of the drains to make sure that there are no leaks.

Dishwasher Connection

Modern food waste disposers are often connected to your dishwasher’s drain pipe. This connection enables your dishwasher to rid itself of any leftover food scraps or residue that it might accumulate while washing your dishes. Where the dishwasher hose and the garbage disposal connect is a common source for leaks. The leaks most often occur when hose’s clamp is not secure enough. Leaks also develop when the dishwasher hose cracks. In order to fix this type of leak, you should either replace the cracked section of hose or tighten the clamp down.

Cracks In the Disposal Body

Last, but not least, as your garbage disposal system begins to age, it grows susceptible to cracking along its interior lining. When this shell develops cracks, water will begin to appear at its seams. If this is the cause of your garbage disposal’s leaks, then there is no method of repairing other than replacing the whole unit.

If you are in the market for a dedicated garbage disposal, check out our top rated models:

Thanks for reading - I would love to hear your comments below.

Justin Curtis

I am not a professional plumber, but I do feel like I am pretty handy :). I would love to hear your comments about this post or others. Thanks for reading!

Click Here to Leave a Comment Below 9 comments
Sharon Reams - January 3, 2017

Thanks for giving such good tips. You may not be a pro but your tips are like a pro 🙂

Rob - January 16, 2017

The disposal exhaust seal is leaking badly. This is the seal that is on the disposal side of the 90 degree exhaust elbow that feeds to the plumbing P-Trap.
What is this seal named and where can one be purchased?

    Justin Curtis - February 9, 2017

    I’d check out your local Home Depot or Lowes, they should have the seal and tell you the name of it.

Dylan - March 19, 2017

Thank you. Very helpful. It’s a crack, so we need to get a new one, but it was so helpful to know what we were looking for.

    Justin Curtis - April 12, 2017

    Glad to help Dylan!

      Chris - May 31, 2017

      Will flex seal work if its a crack? If not why? Flex seal is made specifically to stop leaks from cracks and loose pipes. Thanks

        Justin Curtis - June 5, 2017

        Flex seal should work too.

          Kari - August 7, 2017

          my garbage disposal is leaking from the bottom of the garbage disposal.

          I’m guessing that it totally needs to be replaced.

          Justin Curtis - August 8, 2017

          Most likely.


Leave a Reply: