How to Repair a Clogged Garbage Disposal

Understanding Garbage Disposals

Before diving into repairs, it helps to understand how garbage disposals work. A garbage disposal is installed under the kitchen sink between the sink’s drain and the trap. When turned on, the garbage disposal uses sharp blades and a motor to grind up food waste so it can pass through plumbing.

Over time, grease, bones, celery stalks, onion skins, and other fibrous foods can get lodged in the disposal blades or drainage passages. This buildup causes jams and clogs. Knowing the basic inner workings of a disposal can help you diagnose and fix clogs.

Diagnosing the Clog

Start by trying to turn on the garbage disposal with cold water running. Listen and feel underneath the sink for clues:

  • If the disposal hums but doesn’t grind, this indicates the blades are stuck on a blockage.
  • If the disposal doesn’t hum at all, it likely lacks power. This points to an electrical issue.
  • If you feel vibrations under the sink but no grinding, this suggests a jammed impeller.
  • If the sink drains slowly, excess food particles may clog the drain trap.

Inspect the reset button on the bottom of the disposal unit. If tripped, press to reset. If resetting doesn’t work, unplug the unit before proceeding.

Trying the Allen Wrench Trick

Many jams in a garbage disposal can be cleared with this simple trick:

  1. Locate the Allen wrench that came with your disposal. If you don’t have it, you can use a 1/4-inch Allen wrench.
  2. Turn off the disposal and remove the rubber gasket covering the bottom of its center shaft.
  3. Insert the Allen wrench into the center shaft and twist back and forth. This releases built-up debris to allow the blades to spin freely again.

Before reassembling, confirm the disposal spins easily by turning the bottom motor plate with a broom handle. If the Allen wrench trick fails, try a different method.

Using a Wrench to Unjam the Blades

For stubborn jams:

  1. Disconnect power to the disposal under the sink or at the circuit breaker.
  2. Insert a 1/4-inch Allen wrench into the bottom of the disposal. Work it back and forth to engage the flywheel.
  3. Insert a sturdy wooden broom handle into the top opening of the disposal. Work it back and forth to rotate the flywheel.
  4. Alternate wiggling the Allen wrench and broom handle until you break up the jam. The blades should spin freely.

Checking and Resetting the Disposal

Before turning the power back on:

  • Remove all blockages, double check the blades spin freely.
  • Push the disposal reset button if tripped.
  • Make sure all internal parts are in place. Replace the gasket.
  • Confirm proper electrical connections.

With the electrical disconnected, try eliminating simple drain clogs:

  • Place a bucket under the trap and unscrew the two threaded pieces of the curved pipe.
  • Remove and inspect the trap for obstructions.
  • Use a wire coat hanger to fish out debris.
  • Reassemble the trap pieces once clear.

Tips to Avoid Future Clogs

To prevent future clogs:

  • Run plenty of cold water when using the disposal to flush away particles.
  • Grind citrus peels, eggshells and fibrous veggies in moderation.
  • Avoid starchy foods like rice and pasta which can swell and clog.
  • Limit use of greasy foods that build up.
  • Regularly pour baking soda and vinegar down the drain.
  • Scrape dishes instead of rinsing excess food down the disposal.

Repairing a clogged garbage disposal is often a quick DIY fix. With the proper diagnosis and tools, you can save the hassle and expense of a service call. Just be sure to disconnect power before attempting any repairs.

Frequently Asked Questions About Repairing Clogged Garbage Disposals

Here are answers to some common questions about fixing jammed or clogged garbage disposals.

What if the reset button doesn’t work?

If pressing the red reset button on the bottom of the unit doesn’t restore power, you likely have a deeper electrical issue. Check for a tripped circuit breaker or blown fuse. Make sure the wall switch is on. Test for power continuity on the wires. If needed, call an electrician.

Why does my disposal have a burning smell?

A burning odor usually means the garbage disposal motor is overheating. This often results from the motor straining against a stuck impeller or jammed blades. Try freeing the blockage with an Allen wrench or wrench as outlined above. If not resolvable, the disposal may need replacement.

What if the Allen wrench trick doesn’t unjam the blades?

In stubborn cases where an Allen wrench alone doesn’t work, use a wooden broom handle in conjunction with the Allen wrench as described in the steps above. The increased torque provides more force to break up the clog. Caution: Never put your hands in a running disposal.

My disposal leaks – now what?

A leaking garbage disposal often means the mounting flange is loose or its seal is compromised. Try tightening the bolts securing the disposal to the sink flange. Ensure the flange is evenly sealed under the lip of the sink. Replace the mounting ring if cracked or damaged.

Why does my disposal keep clogging?

Frequent garbage disposal clogs suggest improper use. Don’t put in large fibrous items like husks or bones. Feed waste in slowly while flushing with plenty of cold water. Only put in biodegradable food items. Grind scraps regularly to avoid buildup. Consider replacing older disposals prone to clogs.

When should I call a plumber?

If you can’t diagnose the specific cause of the clog, if disassembly is required beyond routine traps and slip joints, if the motor shows electrical damage, or if the entire disposal needs replacement, it’s best to call a professional plumber.


Learning how to repair a clogged garbage disposal is a handy DIY skill that can save time and money. In many cases, clogs stem from insufficient water flow or easily cleared blockages. Start troubleshooting by checking the reset button, electrical connections, and blades. Use tools like an Allen wrench, wooden broom handle, or wrench to detach debris from the impeller and grinders. Prevent future clogs by monitoring what goes down the disposal. With the proper diagnosis approach and basic tools, you can often fix a jammed disposal yourself in minutes.