There are many reasons for a garbage disposal to leak. It’s not too uncommon for a garbage disposal to start leaking with so many moving parts attached to our kitchen sink drain.
If we can’t tell where the leak is coming from, we might be able to dry off the garbage disposal and search for a wet spot with a dry paper towel. Once we figure out where the leak is coming from, we can usually determine the source of the problem.
It’s easier to troubleshoot garbage disposals when they go out if we know how they work.
What's In This Guide?
Troubleshooting A Leaky Garbage Disposal.
Troubleshooting a leaky garbage disposal problem starts with a visual inspection. Sometimes we can see the water squirting out of a certain area. Other times the water may work its way down the entire garbage disposal unit before dripping out the bottom.
It will look like the garbage disposal is leaking from the bottom, in many cases, this is not always true.
The garbage disposal connects to a drain flange at the bottom of our sink. This drain is pinched between a layer of watertight putty that prevents leakage between the drain and the sink. This putty can start to dry up over time.
Water can work through the cracks and start dripping near the drain underneath our sink when this putty loses its elasticity.
Inside the garbage disposal are two large rotating chunks of metal that help grind down any food or solids we put down our sink drain pipe. An Allen head screw at the bottom of garbage disposals allows us to free up these rotating chunks of metal if they ever get jammed in the main drain line.
If any one of the seals that waterproof the system gets worn, the garbage disposal can start to leak.
After years of use and water constantly dripping to the bottom of the garbage disposal, the casing can begin to rust and crack. If after we’ve checked all the plumbing connections, the drain flange, the drain line connection, and any other obvious source of loose connections, we may just find the water is coming out of the bottom of the garbage disposal unit.
If our garbage disposal leak is from the bottom, it probably needs to be replaced.
Here’s a great video to show easy it is to replace a garbage disposal unit.
What Causes A Garbage Disposal To Leak From The Bottom?
Garbage disposals are one of the most used and abused appliances in our kitchen. We need them to dispose of our waste properly, but they will all eventually go out in time.
Because no water lines are going into the bottom of the garbage disposal unit, this is one of the worst places to spot a leak.
The garbage disposal motor forces the cutter blades around furiously as we constantly push our solids down the drain pipe. When the motor works harder than it should, it can cause the inside of the garbage disposal to heat up. This heat can start to break down the factory seals inside the unit.
When our seal starts to go out, we can’t replace them. We may want to check with our homeowner’s warranty.
When we discover that the leak is on the sides of the garbage disposal, we might get lucky by tightening a few loose connections. If it’s coming from the top of the garbage disposal unit, we might be able to add some more plumber’s putty.
When we discover that the bottom of the garbage disposal is leaking, it’s time to replace the entire unit.
What If Your Sink Is Leaking From Garbage Disposal?
I keep my plastic bags underneath my sink. One day I started to hear a non-stop tapping sound on my stash of plastic bags. I noticed that there was a slight leak coming from my garbage disposal.
As I followed the leak up, I realized it was coming from my sink, where the garbage disposal connects to the drain flange. It was dry drain putty. When it’s not the actual garbage disposal leaking but the area where the garbage disposal connects to the sink, it’s usually by dried-up plumber’s putty.
If we notice that our sink leaks after we just installed a new unit and we did all the garbage disposal repair work ourselves, we just need to add more plumber’s putty. It is necessary to remove all the old putty before putting down a new batch to keep a clean point of contact near the drain.
Unfortunately, the garbage disposal doesn’t have replaceable seals. While a garbage disposal is nearly indestructible, the constant abuse we put them through will eventually wear out the internal seals.
If we notice any leaking from the bottom of the garbage disposal or random cracks in the side of the unit, the seals are rotten.
Did you know? Garbage disposals are factory sealed. When the internal rubber seals go out, we cannot replace them. We will need to change out the entire garbage disposal.
Is It Worth Fixing A Leaking Garbage Disposal?
It’s always worth trying to fix leaking garbage disposal. If we don’t have to replace it, we shouldn’t. It could be just a loose connection or dried-up putty.
In any case, repairing a leaking garbage disposal is by far cheaper than replacing one altogether. There are certain instances where we won’t be able to fix the issue.
In the previous section, we talked about garbage disposal seals wearing out. When these internal seals go, then it’s not worth the time of trying to fix the garbage disposal unit. We might as well just replace it.
Final Thoughts On Why Your Garbage Disposal Is Leaking.
If we just installed a new water heater, and it leaks, we should re-tighten all the connections first.
Next, we check if there’s enough plumber’s putty between the drain flange on the sink to prevent water from seeping through. If we’re working on an old and used garbage disposal, checking for loose pipe connections should still be our first course of action.
On worn units, however, a leak near the top of the drain pipe is almost always caused by dried-up plumbers putty under the drain flange.
If we see that our garbage disposal is leaking from any random area on the garbage disposal casing, one of the internal seals has gone out.
Garbage disposals are meant to take abuse and are built to last a long time. Every garbage disposal unit will eventually need to be changed out.
FAQs On Why My Garbage Disposal Is Leaking
Why is my garbage disposal leaking?
There are many connections in garbage disposals that can come loose. The plumber’s putty around the drain flange can also dry up. Garbage disposals are nearly indestructible but have internal seals that will go out.
What if my garbage disposal seal is leaking?
There are things we can do to stop our garbage disposal from leaking. We can tighten loose pipe connections and add the plumber’s putty. If one of the internal seals has worn out, we will need to replace the garbage disposal.
Can I fix a leaking garbage disposal by myself?
Sometimes we can add a plumber’s putty to the drain flange on the sink or tighten a pipe connection to stop a leaking garbage disposal. In most cases, we can replace garbage disposal ourselves.
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About Plumbing Navigator
We write about "all things plumbing," helping you navigate common questions, repairs, and the best plumbing products on the market.
About Plumbing Navigator
We write about “all things plumbing,” helping you navigate common questions, repairs, and the best plumbing products on the market.
