Garbage Disposal Leaking? This’s Why and How to Fix It

What are the Causes for a Leaking Garbage Disposal?

A garbage disposal can leak from the bottom, top or even side. In most cases, the cause the of the leak is a worn out seal or loose connection due to the vibrations, which means it is not always that you have to replace the unit.

Always take your time to investigate the source of the leak first. That way you will know how to fix it, or replace it if it cannot be fixed.


A leaking garbage disposal is a sign of a loose sink flange which causes it to leak from the top, or worn out internal seals which causes it to leak from the bottom. Garbage disposals leaking from the side are caused by loose dishwasher or drainpipe connections, or worn out gaskets.

To fix a garbage disposal leaking from the top, disconnect it from the sink and reseal the sink flange with fresh plumber’s putty before connecting it back. If it is leaking from the side tighten the pipe connections or replace the gasket. Garbage disposals leaking from the bottom will almost always need a replacement.

While, you can still run your garbage disposal while it is leaking, it is not recommended especially if it is leaking from the bottom. Garbage disposals are designed to trip whenever there is a power leak but any system can fail, leading to electrical shock.

A garbage disposal should last for about 10 years. If you have a leaking garbage disposal that is about or older than 10 years you should consider replacing it. A constantly humming garbage disposal is another sign that it needs a replacement.

Troubleshooting a Leaking Garbage Disposal


The first thing to do whenever you notice your garbage disposal leaking is to determine the source of the leak. That way you will not waste time replacing things which need not replacing.

There are a few areas that will be of interest to you. These are:

  • Sink flange/ top gasket
  • The bottom
  • Dishwasher pipe connection
  • Drainpipe connection

When the garbage disposal is leaking from the bottom, it may sometimes appear as if it is leaking from the reset button, power cord or bottom screw. This is why it is usually hard to repair a disposal leaking from the bottom, and a replacement is always the better option.

To investigate the source of a garbage disposal leak, follow the following steps:

  • Turn off power to the garbage disposal and unplug it
  • Use a rag to wipe the entire garbage disposal dry.
  • Plug off the sink with a stopper.
  • Pour about a gallon of water in the sink.
  • Add food color or dye to the water.
  • Wait for 15 minutes.

In this experiment, we are try to establish if the garbage disposal is leaking from the top. It is always easy/better to do that with standing water in the sink.

Duck under the sink and check if the dyed/colored water appears around the top of garbage disposal gasket. If it does, the garbage disposal is definitely leaking from the top.

If no colored water does appears under the sink, remove the sink stopper and let the water flow inside the garbage disposal. Colored water on the reset button, power cord or bottom screw indicates the garbage disposal is leaking from the bottom.

If the colored water instead appears on the side, it means the garbage disposal pipes are loose, or the gasket is simply worn out. You will therefore need to tighten the connection or replace the gasket.

How to Fix a Garbage Disposal Leaking from the Top

A garbage disposal is usually connected to the sink using a flange, which goes over the top of the sink drain. To create a watertight connection, plumber’s putty is usually spread under the rim of flange where it sits on the sink.

Under the sink, the garbage disposal and the sink flange are connected using a mounting bracket with the help of 3 screws/bolts and a mounting ring. The bottom part of the sink flange has a groove which the mounting ring engages and with the help of the screws the 2 mounting bracket plates are compressed together.

Any time your garbage disposal is leaking from the top, this connection is usually the culprit. Either the mounting screws are too loose and hence breaking the seal, or the plumbers putty under the flange has eroded, causeing it to leak.

To fix a garbage a disposal leaking from the top you will first need to remove it, reseal it and then install it back. This is actually an easy process as I will demonstrate below.

How to Reseal a Garbage Disposal

  • Make sure that you have turned off power to the garbage disposal.
  • Disconnect the garbage disposal from the drainpipe. Often, this connection is usually hand tight. Only use a wrench if you cannot loosen it with your hand. Before loosening the connection, place a small bucket under it just in case there is water in the pipes.
  • On the sink mounting bracket, you will see some round slots. Insert a screwdriver on one of the slots. Holding the garbage disposal firmly with one hand and the other hand on the screwdriver, turn the screwdriver ¼ turn counterclockwise. The garbage disposal is quite heavy so be careful not to drop it.
  • Use a screwdriver to loosen the 3 mounting bracket screws. Once loose, use a flathead screwdriver to pry out the ring and in the process free up the flange.
  • Get up on your feet and remove the sink flange from the top of the sink.
  • Use a putty knife to scrape off old plumber’s putty from the under the flange as well as the top of the sink drain.
  • Roll a pencil-sized bead of plumber’s putty between your hands and spread it nicely under the rim of the sink flange.
  • Insert the flange in the sink drain and push it down as much as you can. A good sign that you have a tight seal is when plumber’s putty squeezes out from all around the edge of the flange.
  • In order to install the garbage disposal mounting bracket, you will need to place a heavy object inside the sink directly above the flange, to prevent it from moving about and ruining the plumber’s putty. The garbage disposal itself is a good item.
  • From under the sink, push in the gasket followed by the mounting braking over the flange and insert the ring in the flange’s groove. Tighten the screws while holding the mounting assembly in place with the other hand.
  • Now lift the garbage disposal, align it with the mounting bracket, push it inside then turn it clockwise to engage it.
  • Connect the drainpipe to the garbage disposal as well.
  • check if the leak has stopped.

And basically that is how to fix a garbage disposal leaking from the top

How to Fix a Garbage Disposal Leaking from the Side Pipe

If your garbage disposal is leaking from the sides, either the clamp connecting the dishwasher hose to the garbage disposal is loose, the disposal-drainpipe connection is loose or its rubber gasket is worn out.

If you have a dishwasher, it is connected to the garbage disposal on the side using a rubber hose. The rubber hose is secured to the garbage disposal’s inlet pipe using a metal clamp.

If the leak is on the dishwasher’s connection to the disposal, the first thing you should do is inspect the condition of the hose. Is it cracked? Is it all the way in all does it appears pulled out a little?

If the hose is cracked you will definitely need to replace it. On the other hand if it looks to be in good condition but slightly loose or pulled out a little, push it further in and tighten the clamp with a screw driver.

A garbage disposal has a 7-shaped pipe which allows it to be connected to the sink’s drainpipe. This pipe is connected to the garbage disposal using metal plates which are backed up by a rubber gasket to form a water tight seal.

If you notice water leaking from that connection, either the connection is loose or the rubber gasket is worn out. Grab a screw driver and tighten the connection. Check if the leak is fixed.

If water is still leaking from the connection, disconnect it using a screwdriver and inspect the condition of the gasket. If the condition is worn out you will definitely need to replace it. On the other hand if the gasket is just warped, you can try to change it to face the other way and connect the pipe back. This should fix the problem.

Garbage Disposal Leaking from the Bottom


Garbage disposals leaks from the bottom for 2 reasons. Either the internal seals are worn out and no longer restraining water, or the bottom part is cracked. In both of these scenarios, you will need to replace the garbage disposal.

The garbage disposal internal seals protect water from getting to the motor, which is located at the bottom of the unit. If the seals are no longer restraining water, it will appear as though the garbage disposal is leaking from the reset button or power cord.

This is however not to say that the seals cannot be replaced. They surely can. It is just that the cost analysis of both indicate to buying a new one as the better alternative, especially if you are paying someone for the repair

Seasoned DIYers can however find value in replacing the seals. Just remove the garbage disposal and set it in a working table. You will see screws around the mid-section of the unit.

Remove the screws and take the unit apart. Replace the seals and put it back together. Connect it to the sink and check if the leak has stopped.

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