DIY Guide To Repairing A Leaking Kitchen Garbage Disposal

Is your kitchen garbage disposal leaking water and causing a mess under the sink? Leaking disposals are a common problem that can often be fixed with some DIY troubleshooting and repairs.

Dealing with a leaky garbage disposal can be frustrating. Water dripping from below the unit or pooling around the base of your sink indicates a problem needs attention. Thankfully, armed with the right knowledge, you can track down the leak and make the necessary repairs yourself in many cases. Read on to learn how.

What Causes a Garbage Disposal to Leak?

Before diving into repairs, it helps to understand what causes leaks in the first place. There are a few common culprits to be aware of:

Clogged Drain Lines

Like any drain, garbage disposals can get clogged with food debris over time. Partial obstructions in the drain line restrict the water flow. This forces water to back up and leak from seals that aren't designed to hold back pressure.

Using a drain snake or plumber's auger to clear out the drain line is often the solution. You may also need to remove the disposal and physically clean out the drain. For stubborn organic clogs, try boiling water or chemical cleaners.

Damaged or Worn Seals

The seals between the disposal unit and the sink drain wear out over time. Food particles passing through can slowly erode the rubber gaskets. The constant vibration of the disposal can also loosen connections.

Inspect the disposal's seals for cracks, gaps, or excessive wear. Tightening bolts may help, but replacing worn out gaskets and O-rings is usually required to stop leaks between mating surfaces.

Cracks and Corrosion

The grinding chamber inside the disposal is subjected to a lot of abuse. Over time, cracks and holes can develop in the metal housing. Rust and corrosion will also eat away at the body.

Consider replacing the entire disposal if the housing is too far gone. For small leaks, you can sometimes patch cracks and holes temporarily with epoxy adhesives or metal epoxy putty.

Improper Installation

If a disposal was installed incorrectly, leaks can develop around the mounting assembly and discharge tube. Leaks typically appear right away in these cases rather than later in the machine’s service life.

Check for alignment issues and tighten the mounting bolts. Adjusting the discharge tube may also help stop water from dripping during operation.

How to Troubleshoot a Leaky Disposal

Pinpointing the exact source of the leak is the first step towards fixing the problem. Here are some tips for troubleshooting common leaks:

Inspecting Visible Leaks

Wipe down the outside of the disposal unit and look closely for dripping water. Use a flashlight to peer inside the grinding chamber for cracks and moisture.

Leak locations help indicate the problem. Leaks at the base point to drain line or seal issues. Leaks along the housing or mount signal corrosion and cracks.

Checking Mounting Bolts

Leaks often develop around the mounting assembly. Verify the flange and gasket are seated flush to the underside of the sink. Try tightening the mounting bolts evenly to see if that stops water from escaping.

Assessing Drain Line

Disconnect the discharge tube where it attaches to the disposal or drain tailpiece. Turn on the faucet and check if water flows freely. Insert a drain snake or auger to clear any blockages.

Testing Motor Function

With the power disconnected, insert an Allen wrench in the bottom of the unit to turn the motor spindle and blades by hand. Listen and feel for odd grinding or catching that could indicate jammed impellers.

How to Fix a Leaky Garbage Disposal

Once you’ve diagnosed the leak, here are tips for completing common garbage disposal repairs:

Unclogging Drain Lines

For sludgy organic clogs, use a plumber's snake to break up and extract debris. Or apply a boiling water flush. For mineral deposits, try an acidic drain cleaner.

To avoid future clogs, be mindful about what goes down the disposal. Grind ice cubes regularly to clean the blades and pipes.

Replacing Seals and Gaskets

Remove the disposal and detach it from the sink flange. Clean seal surfaces then apply plumber's putty to seat the new gasket. Reinstall the unit with a watertight connection.

Use the manufacturer instructions to replace any inner seals or O-rings. Make sure to get an exact replacement.

Tightening Mounting Assembly

Remove pipes to get a clear view of the flange underneath. Realign if needed, verify the gasket is seated evenly, and tighten all three mounting bolts incrementally.

Don't overtighten bolts. The gasket should be snug but not crushed or distorted.

Installing New Disposal

For extensive rust or cracking, replacement is the best option. Use a universal mount kit and adjustable ring for easy installation. Make sure discharge tube aligns cleanly.

Modern disposals are more resistant to leaks and corrosion. Upgrade to a quieter, more durable model.

Preventing Future Leaks

With some simple maintenance, you can get years of leak-free service from your disposal:

Regular Maintenance

Run water before and after grinding to flush debris. Grind citrus peels and ice cubes to scrub the chamber and blades clean.

Check seals annually and tighten mounting bolts to stop leaks before they start. Lubricate grinding parts with mineral oil.

Avoid Certain Items

Never put fibrous or starchy foods down the disposal. Egg shells, onion skins, rice, and pasta can swell up or get lodged in pipes.

Grease and fat can slowly accumulate and lead to clogs. Scrape plates first and avoid pouring fats down the drain.

Check Mounting Bolts

The metal flange connecting the disposal to the sink can loosen over time. Verify the mounting bolts are snug once a year to prevent leaks.

Use a backup flange kit if corrosion has damaged the original flange. Replace worn out bolts.

Know When to Call a Plumber

Extensive corrosion or cracking in the grinding chamber may require more repairs than DIY is practical. Let a pro tackle:

• Complete disposal replacement and installation
• Leaks between cabinet floors or into walls
• Electrical issues with the grinding motor

For complex leaks or mounting issues, it's best to have a professional install your new garbage disposal to avoid future problems.

Don't let a leaky garbage disposal go unchecked. With some handy troubleshooting, you can likely find the source of the leak and make needed repairs yourself. Just be sure to take precautions when working inside the unit.

Regular maintenance and avoiding misuse will prevent most leaks down the road. But with this guide, you now have the knowledge to diagnose issues and get your disposal working properly again.