Informational Guide

Fixing a Garbage Disposal Leak

Stuck with a garbage disposal leak? Luckily, it’s normally an easy fix. Here are 8 ways to fix a garbage disposal leak without a plumber.

by Ian Haynes

A fully functioning garbage disposal makes life a lot easier and helps to protect your plumbing. However, a leaking garbage disposal can impact its effectiveness, causing water damage to your cabinet and your floor. It can also lead to wider problems in your kitchen if you don't get it fixed quickly.  

To avoid an expensive problem, you need to fix the garbage disposal leak as quickly as possible. This guide will help you understand why the issue has occurred and how to solve the problem yourself.  

There are some common reasons leaks occur in your garbage disposal which means you can generally diagnose the problem and establish the solution fairly easily. 

Leaks typically occur from three places: the top, the middle, or the bottom of the garbage disposal, and we've given a list of the common causes below.  

To complete any kind of repairs on your garbage disposal, you will need: 

Garbage Disposal Leak

Remember to turn off the power completely before you undertake any repair or maintenance work. 

1. Loose Drain Lines 

If the leak is coming from the bottom of your disposal, then it could be due to loose drain lines. At the base of your disposal, you should have two pipes, a thick sewer line, and a thin dishwasher drain line. 

These parts see a lot of use, and if they aren't fitted correctly, then water will drip from them. If you can see any visible water dripping from them, you need to follow these steps:  

  • Locate the clamp that holds the garbage disposal to the dishwasher. Using a screwdriver, tighten the screws which connect the garbage disposal to the dishwasher and look to tighten the screws which hold the dishwasher disposal line in place.  
  • Check the drain line attachment to make sure it’s tight. Use a screwdriver to tighten if necessary.  

Remember to check your drain lines regularly for any drips. Over time they can become worn and damaged.  

2. Split Or Cracked Disposal Body 

Water Leak From Garbage Disposal

If you notice a leak from the middle of your disposal, it could be a crack in the body. This is the worst type of leak because it usually means your garbage disposal is damaged beyond repair. These cracks typically happen because it's been knocked, often when somebody is searching or retrieving something from the cupboard.  

Unfortunately, there isn't a quick fix for this, and if you see a split or crack, then you probably need to replace your garbage disposal. You should consider placing your new one in a safer location to prevent is being knocked or damaged in passing.  

3. Leaky Sink Flange 

If the leak is coming from the top of your disposal, then it could be a leaking sink flange. This flange is located right at the top where the disposal meets the drain and is used to prevent dirt from building up in your sink. If you can see leaking water coming from this area, you need to replace it.  

Water Leak From Bottom Of Garbage Disposal

A leaky flange is generally caused by either weak putty that can't stop water or because it's loose. You will need to replace the putty and can do so by following these steps: 

  • Remove the screws which attach the disposal to your main drain and any other hoses or connections.  
  • Locate the mounting ring, which is used to secure the garbage disposal underneath the sink, and remove it. This should allow you to fully remove the garbage disposal and lay it on an even surface.  
  • Use a wrench and screwdriver to loosen the bolts and remove the mounting assembly. This should be fairly easy to remove, and you can lay it down next to your garbage disposal.  
  • Now you can remove the plumbers putty on top of the flange at the top of the disposal. Clean the top of the flange with a wet cloth to remove any dirt.  
  • Take your plumbers putty and roll it in your hands until it's thin. Shape it in a circle around your clean flange, so it goes around the entire perimeter. The flange should now fit into the drain.  
  • Reattach your mounting assembly and then reinstall the garbage disposal, reconnecting all the attachments.  
  • Test your garbage disposal to make sure it’s no longer leaking.  

4. Worn Out Gaskets 

Worn out gaskets are one of the leading causes for a leaking garbage disposal, and they will usually cause a leak from the top of the unit. You should check the gasket between the flange and the rubber seal of the garbage disposal. If there’s any discharge, then it means the gasket is faulty.  

Gaskets will naturally become weakened over time, so if you have an old garbage disposal, then you are more likely to encounter this problem. Faulty gaskets can also be caused by poor fitting if it's improperly sealed around the edges, and gaskets can also dry up if they aren’t used regularly, so if you don't use your disposal much, it can cause it to leak.  

To solve the issue, you need to swap the existing gasket for a new one. You can do this by following these steps: 

  • Detach the drain and remove the plug from your garbage disposal, so it's completely disconnected.  
  • Unlock the disposal unit by holding the mounting nut and rotating the device clockwise. This should fall downwards into your hand when loosened.  
  • You should now be able to see the rubber gasket, so remove the old one and place your new one in the exact same position. Make sure it sits flat.  
  • Reattach the garbage disposal and secure it in place.  
  • Make sure it is all tightly sealed, and then reattach the water supply and plug. Test the unit to make sure it’s no longer leaking.  

5. Dishwasher Connection 

Garbage disposals are often connected to a dishwasher so they can safely deal with food waste. A pipe or hose is used to connect the disposal and the dishwasher, and this can, over time, develop a leak.

If you notice water coming from the side of your disposal, then this is likely the cause, and it’s generally because the hose has become cracked and loose.  

If you notice a leak coming from your dishwasher connection, then you need to replace the hose. You can do this fairly easily by buying a replacement hose and attaching it to both ends yourself.  

Why Does My Garbage Disposal Leak

image source: omeinspectionms.com

6. Loose Seal Or Pipes 

Garbage disposals are usually kept under the sink, and that often doubles up as storage space. If your garbage disposal is knocked, it can impact the seals and pipes connected to it and loosen them, so they begin to leak. If you can see any visible water dripping from the connections and pipes, this is probably what happened.  

Look for any pipes or connections out of place and move them into position, using a screwdriver or wrench to tighten them. If the leaking persists, then you can use plumbers putty to create a sealing ring.  

7. Leaking Reset Button 

If your garbage disposal is leaking from the reset button,  this usually means there's some severe damage to the disposal, and it's going to be very difficult to repair. There are some options, but generally, they are just quick fixes, and you can't sort the issue yourself at home. You can consult a professional, but it may become costly. 

If your garbage disposal is still in warranty, it may be worth looking at options, but if not, then you will need to look for a new model.  

8. Loose Or Damaged Discharge Pipe 

If your garbage disposal is leaking from the bottom and you’ve already tried troubleshooting everything else on the list, then it may mean there’s a problem with your discharge pipe. This is the large pipe at the base of the unit, and you should be able to see if there are visible signs of wear and tear or any obvious leaking coming from it.  

You can use a wrench to try and tighten the flange and see if that stops the issue. If not, you can use a plumber's putty to change the seal between the discharge pipe and the holding nut on the garbage disposal.  


Tips To Prevent Future Garbage Disposal Water Leaks 

Preventative measures are always the best course of action, and there are a few things you can do to stop leaks before they even occur:  

Clean Regularly  

Cleaning your garbage disposal regularly and removing any blockages is the best way to keep it functioning effectively for longer. You can use a paper towel to wipe the rubber ring at the top of the disposal and clean any dirt from the outside.

You can toss ice cubes into the disposal to help the mechanism, and you can even use vinegar or lemon juice to make ice cubes which will dissolve any blockages in the machine. If your garbage disposal does start to smell, you can put cut up citrus fruit and rinds into the machine.  

Avoid Fibrous Or Starchy Foods 

Fibrous and starchy foods block up your garbage disposal and stop it from running correctly. Things like potato peels, onions, and fruit seeds will all get stuck in the mechanism and harden over time, making them a real issue. If you do want to put these through the garbage disposal, then you should cut them up into small portions and run them through in batches.  

Don’t Put Hard Waste In Your Garbage Disposal 

Hard food waste can seriously damage your mechanism and stop your disposal from working correctly. If this does become lodged, then you'll need to unclog your garbage disposal to get it working, which can be tricky. Here’s a full list of what not to put in a garbage disposal 

Remember, disposals aren't built to last forever, and even if you maintain them correctly, you may still need to replace your garbage disposal one day.  


People Also Ask (FAQs)

How much does it cost to fix a leaking garbage disposal? 

If you're doing the work yourself, then it shouldn't cost much more than $50 to get replacement parts and tools to fix your garbage disposal. If you consult a professional, it could cost anywhere from $70-$200.  

Can I run my dishwasher if my garbage disposal is leaking? 

Yes. A leaking garbage disposal won't send any dirty water back up so your dishes will be cleaned, though it will send more water down, which will leak into your home.  

What is the life expectancy of a garbage disposal? Can you replace one yourself? 

Most garbage disposals will last about 10 years if you maintain them properly. After that, you can replace them yourself, and we've created a full guide on replacement here 

Is it OK to pour boiling water down a garbage disposal? 

Boiling water can melt your PVC pipes and cause damage to your plumbing, so you should avoid pouring it down the sink. Hot water is fine to be poured through your garbage disposal, though.  

Why do garbage disposals need to be reset? 

Garbage disposals need to be reset to stop them from running when there's a blockage. This helps protect the mechanism and prevent it from overheating.  


Conclusion

good garbage disposal makes life a lot easier, but a leaking garbage disposal can be a nightmare. Hopefully, this guide has given you everything you need so you can diagnose and fix the problem, and some useful information about how to stop leaks occurring in the first place.  

Ian Haynes is an expert writer who has successfully deployed over 500 plumbing pages and other related content. He has an excellent understanding of home plumbing issues and translates his experiences via Plumbing Lab so readers can have a better understanding of common household problems. Outside of his work, Ian likes exploring Brooklyn with his Labrador.

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