If your kitchen sink smells bad or sounds off, there’s a chance your garbage disposal blades need some attention. Although these units are made to grind food waste with ease, they don’t stay clean on their own. With regular use, grease and grime collect inside. But how do you even reach something you can’t see? That’s what we’re going to explore in this guide—step by step.
How Garbage Disposals Actually Work
Most people think a garbage disposal works like a blender with sharp spinning blades that tear everything apart. It’s loud, rough, and sounds like it’s chopping things to pieces. You might picture it slicing through food waste like a kitchen knife.
But that’s not how it really works. Inside the disposal, there are two small, metal impellers instead of sharp blades. These impellers spin rapidly and fling food scraps outward. As the scraps hit the grind ring—a textured metal surface—they’re broken down into tiny bits. Once small enough, the waste is flushed away by water through the drain.
It’s a smart little setup. Nothing inside is actually cutting anything—the force of the spinning is what gets the job done. The inside stays sealed, and all the action happens in that chamber. So while it sounds aggressive from the outside, it’s more of a grinding motion than anything else.
Can You Clean Blades on a Garbage Disposal?
You might think cleaning the inside of your garbage disposal means reaching in and scrubbing the blades. But it doesn’t work like that. There’s nothing inside you can pull out or wipe down. The impellers don’t move unless the unit is running, and they’re not designed to be touched.
That doesn’t mean they stay spotless, though. Bits of food, grease, and sludge can stick around inside the chamber, especially on the impellers and the grind ring. So while you can’t scrub the “blades” directly, you can clean the inside of the disposal. It’s more about flushing out the buildup than scrubbing parts. And if you don’t do it now and then, the symptoms will let you know something’s wrong with the unit.
How Do I Know If My Garbage Disposal Needs Cleaning?
A garbage disposal that needs its insides cleaned doesn’t hide it well. It starts showing little signs. Some you can hear, others you can smell. If you catch them early, you’ll save yourself from a bigger mess later. Here are four symptoms to watch for:
Bad Odors
If there’s a sour or rotten smell coming from your sink, it’s probably not the drain—it’s the garbage disposal. Food waste sticks to the inner parts and starts to decay, especially when grease or soft scraps are left behind. Running water won’t rinse it out once the smell sets in. If the odor keeps returning, that’s a sign the inside of the garbage disposal needs a thorough cleaning.
Unusual Noises
Garbage disposals aren’t quiet, but you get used to the sound they normally make. If yours suddenly starts rattling, grinding, or making odd clunking noises, that’s not normal. It usually means something’s stuck inside or the impellers aren’t spinning freely. A simple cleaning might be all it needs to go back to running smoothly.
Slow Draining
When water starts pooling in the sink and takes forever to drain, it could mean there’s a buildup of grease, food bits, gunk, or whatever in the disposal. The more it collects, the harder it gets for water to pass through freely.
Ineffective Grinding
A garbage disposal normally grinds food waste in a few seconds. If yours is taking longer to finish the job, it means the grinding is not up to par, and the so-called “blades” that you think you can sharpen now need a clean.
How to Sharpen a Garbage Disposal: Step-by-Step Cleaning Process
If done right, sharpening the inside of your garbage disposal, especially the impellers and baffle, takes a few minutes. Here’s how to do it step by step.
- Before doing any maintenance, always turn off the power to your disposal. Unplug the unit if possible, or switch off the circuit breaker. Never stick your hand inside the chamber, even if it’s off.
- Put on cleaning gloves and grab an old toothbrush or small scrub brush. The first thing to clean is the baffle by hand with a toothbrush. It is the rubber seal just inside the drain. It keeps silverware from falling in and helps reduce noise.
- Run warm water and use a little dish soap on the brush. Scrub around the top and, importantly, the underside of the baffle where grime usually collects.
- Once done, drop a few ice cubes into the garbage disposal. Ice is tough enough to knock loose food buildup on the impellers and grind ring without damaging anything.
- Then, pour in half a cup of white distilled vinegar. After that, run cold water and the garbage disposal for a few seconds. Now, the garbage disposal is back to sharp enough to do what it does best.
- Finally, add a few citrus peels, not whole fruits, like orange or lemon. The natural oils lubricate the disposal and leave behind a fresh citrus smell.
Maintenance Tips to Keep It Sharp
The grinding parts inside your garbage disposal do more than just chop up scraps—they’re the reason your sink doesn’t smell like last night’s dinner. When the impellers are clean and working right, they break down food quickly so it flushes away without clogging the drain. That way, your sink doesn’t start smelling or backing up with old scraps.
Keeping those parts clean also means your motor doesn’t have to struggle. If food grinds down easily, the disposal runs without weird sounds or shaking. That makes the whole unit last longer and saves you from calling a plumber. The impellers aren’t sharp like blender blades, but they still need the occasional cleanup to work the way they should. A quick spin with ice knocks off the grime so the impellers move the way they should.
Here are a few habits that help your garbage disposal stay in good working order and keep the cleaning at bay for a long time:
- Run cold water while it’s on: Cold water keeps grease and fat solid, so they flush out instead of sticking to the insides.
- Skip fibrous foods like celery, pasta, or potato peels. They tangle around the garbage disposal’s inner parts and slow everything down.
- Avoid pouring grease or oil down the sink drain: They harden and clog up the disposal and the pipes.
- Use it regularly: Like anything else with a motor, it works better when it stays active.
When to Call a Professional?
If your garbage disposal still smells bad, grinds weakly, or makes weird noises even after you’ve cleaned it, there’s probably more going on underneath. When it keeps clogging, leaking, or just hums without spinning, it could mean the motor’s jammed, there’s an electrical problem, or something inside is busted.
This isn’t one of those things you want to take apart on your own. The parts inside are fitted tightly and accurately, and replacing just one piece isn’t always possible. It’s better to call someone who knows what they’re doing. California Coast Plumbers sends out trained techs to your home who can check your disposal, figure out what’s wrong, and fix it before it turns into something expensive, like replacing the whole unit. We don’t guess—we get straight to the issue and handle it the right way.