Top 10 Most Common Garbage Disposal Repair Questions Answered

1. Why did my garbage disposal suddenly stop working?

A garbage disposal that suddenly won’t turn on usually has an electrical or overload issue. First, check if it hums when you flip the switch.

• No sound at all:

  • Make sure it’s plugged in.
  • Press the red reset button on the bottom of the unit.
  • Check your breaker panel for a tripped circuit.

• Humming but not spinning: It’s likely jammed (see the next FAQ).

If you’ve confirmed power, pressed reset, and it still won’t start, the motor may be burned out or the internal wiring damaged. At that point, it’s best to call a professional or consider replacement, especially if the unit is 8–10+ years old.

2. Why is my garbage disposal humming but not grinding?

A humming noise without grinding usually means the motor is getting power, but the grind plate is stuck. This is often caused by hard objects like bones, fruit pits, or a piece of metal wedged inside.

Safe troubleshooting steps:

1. Turn off power at the switch and breaker.
2. Shine a flashlight into the disposal and look for visible obstructions.
3. Use tongs or pliers (never your hand) to remove anything stuck.
4. Insert a disposal wrench or an Allen key into the hex hole on the bottom and gently turn back and forth to free the plate.
5. Restore power and test.

If it still hums or trips the reset button repeatedly, the motor could be seized. That’s the point to call a professional or replace the unit. ⚠️ Never try to move the blades with your fingers.

3. Why does my garbage disposal leak from the bottom or under the sink?

Leaks can come from several areas, and the location of the drip helps you find the cause. Place a dry paper towel under the unit and run water to see where it wets first.

Tighten hose clamps and mounting screws if they’re loose. You can also reseal the sink flange with plumber’s putty. However, if water is leaking from the very bottom of the disposal, the internal seals are usually worn out. In that case, it’s almost always cheaper and safer to replace the disposal rather than repair it.

4. Why is my garbage disposal draining slowly or backing up?

A slow-draining or backed-up disposal usually points to a clog in the drain line, not inside the disposal chamber itself. Grease, fibrous foods, and starches can build up in the P-trap or further down the pipe.

Try this sequence:

1. Run cold water and the disposal for 30–60 seconds.
2. If still slow, turn off power and check the P-trap (U-shaped pipe) for clogs. Place a bucket underneath and remove it to clean out debris.
3. Use a sink plunger on the affected side of a double sink (block the other drain).
4. Avoid chemical drain cleaners—they can damage parts and are unsafe if you later remove piping.

If multiple sinks back up or you’ve tried clearing the trap without success, you may have a deeper plumbing blockage. That’s when it’s smart to call a plumber. 🛠️

5. Why does my garbage disposal smell so bad, and how do I get rid of odors?

Bad smells usually come from trapped food particles stuck under the splash guard, in the grind chamber, or along the drain line. Over time, they decompose and create a strong odor.

To clean and deodorize:

• Flush with hot water and dish soap for a few minutes.
• Turn off the unit and scrub the rubber splash guard (baffle) with an old toothbrush—this is often the worst offender.
• Grind a few ice cubes with a tablespoon of rock salt to help knock debris off the grind plate.
• Follow with lemon or orange peels for a fresh scent 🍋.

Avoid using straight bleach regularly; it can be harsh on rubber components. If smells return quickly, you may have built-up grease deeper in the line and a plumber’s cleaning may be needed.

6. What foods and items should I never put in a garbage disposal?

Knowing what not to grind is one of the best ways to avoid repairs. Some items can jam the blades, dull the grind plate, or clog your pipes.

You can grind small amounts of soft food scraps with plenty of cold water. When in doubt, scrape it into the trash or compost instead. Repeated abuse is a major cause of motor failures and plumbing clogs.

7. How do I safely unjam or reset my garbage disposal at home?

A jammed disposal is common and often fixable if you follow strict safety steps.

Step-by-step guide:

1. Turn off the wall switch and then shut off the breaker for extra safety.
2. Look into the disposal with a flashlight. Remove visible debris using tongs or pliers only.
3. Insert a disposal wrench (or Allen key) into the hex socket on the bottom of the unit.
4. Turn the wrench back and forth to free the grind plate until it moves more easily.
5. Press the red reset button on the bottom.
6. Restore power, run cold water, and briefly turn the disposal on.

If it trips the reset button again or jams frequently, the motor or internal parts may be failing. That’s the time to call a professional or consider replacement. ⚠️ Never reach in with your hands, even if the power is off.

8. Why is my garbage disposal making loud grinding, rattling, or metal noises?

Unusual noises—especially metal-on-metal or rattling sounds—usually mean there’s a foreign object in the disposal. Common culprits include silverware, bottle caps, small screws, or bones.

Do this immediately:

1. Turn off the disposal and cut power at the breaker.
2. Use a flashlight to inspect the chamber.
3. Remove any items with tongs or pliers.
4. Gently rotate the grind plate with a wrench from the bottom to check for free movement.

If you hear grinding even after clearing objects, the impellers or housing might be damaged or misaligned. Continuous operation in that condition can wear out the motor fast. In that case, have a technician inspect the unit. Sometimes, replacing the disposal is more cost-effective than fixing bent internal parts.

9. Should I repair or replace my old garbage disposal?

Whether to repair or replace depends on age, damage, and repair cost. Most disposals last 8–12 years with normal use.

Consider repair if:

• The issue is minor (jam, clog, loose connection).
• The unit is under 7–8 years old.
• Repair cost is low compared to a new unit.

Consider replacement if:

• It leaks from the bottom (failed internal seals).
• The motor is burned out or seizing frequently.
• The unit is 10+ years old and noisy or weak.
• Repair estimate is 50% or more of the price of a new disposal.

Upgrading to a newer model can give you quieter operation, better grinding power, and improved efficiency, often making replacement the smarter long-term choice.

10. Why does my garbage disposal affect my dishwasher or kitchen sink?

Your garbage disposal and dishwasher often share the same drain line, so problems in one can affect the other. Common scenarios:

If your dishwasher is new and won’t drain, check that the knockout plug in the disposal’s dishwasher inlet was removed during installation.

To troubleshoot:

1. Clean the P-trap and drain lines.
2. Ensure the dishwasher hose is secured and elevated in a high loop or connected to an air gap.
3. Clear any clogs in the disposal before running the dishwasher.

If water backs up into multiple fixtures or you find no obvious blockage, a licensed plumber should inspect for deeper drain issues.

Helpful Tips for Keeping Your Garbage Disposal Running Smoothly

• Run cold water before, during, and after use for 15–30 seconds to flush food particles through the pipes.
• Feed scraps gradually, not all at once, to avoid overloading the motor and drain.
• Grind a handful of ice once a month to help knock built-up debris off the grind components.
• Clean the splash guard regularly with dish soap and a brush—it traps the most gunk and odors.
• Avoid grease, fibrous foods, and large bones, even if the unit is “high horsepower.” Prevention beats repairs.
• Listen for changes in sound or performance; catching small issues early can prevent major breakdowns and water damage.