Stop garbage disposal leaks: How to replace a faulty sink flange

Does your kitchen sink resemble a miniature lake whenever you flip on the garbage disposal? A leaky disposal is more than just a nuisance—it can be downright messy, especially if the sink flange is to blame. But don’t stress—we’ve got your back. Let’s tackle this fix together, so you can get your kitchen running smoothly again.

The tips in this article might not exactly fit your specific appliance. We try to give advice that works for most DIY repairs, but different models can have their quirks—whether it’s in the steps, error codes, or the parts you might need. For the best results, check out your appliance’s manual, or feel free to reach out to us if you’ve got questions.

Identify the leak

Hold on before you fetch your toolbox—let’s figure out exactly where that leak is coming from. Garbage disposals can drip from a bunch of spots, so nailing down the source is key to fixing it right.

Signs of a faulty sink flange

The sink flange is that top part of your garbage disposal that hooks up to the sink drain. If you’re seeing water collecting under the sink or dripping from the top of the disposal, chances are the sink flange is loose or shot.

Inspect for leaks

1. Empty out everything from under your sink so you’ve got room to work.
2. Grab a flashlight and check out the disposal and nearby pipes.
3. Run some water into the sink (without turning on the disposal) and watch for any drips or dampness around where the sink flange is.
4. Switch on the disposal and look again—some leaks only happen when the unit’s up and running.

If you spot moisture around the sink flange, it’s probably time to replace or reseal it.

Tools and materials you need

• Plumber’s putty
• Pipe wrench or adjustable wrench
• Screwdriver
• Bucket or some towels (to catch any leftover water)
• New sink flange (if the old one’s busted)

If you’re scratching your head about finding the right parts, take a peek at our guide on how to find your appliance’s model number.

Replace the sink flange

Swapping out a bad sink flange might seem intimidating, but trust me, with some patience and a bit of know-how, you can handle it. Here’s the lowdown.

Step 1: Disconnect the garbage disposal

1. First things first—make sure you’re safe by cutting off power to the disposal. If it’s plugged into an outlet, just unplug it. If it’s hardwired, flip the circuit breaker off.
2. Stick a bucket or some towels under the sink to catch any spills.
3. Loosen the nuts holding the drain pipe to the disposal and disconnect it.
4. If there’s a dishwasher hose hooked up, disconnect that too.

Step 2: Remove the old flange

1. Find the mounting ring at the top of your disposal.
2. Use a screwdriver or whatever tool fits to turn the mounting ring counterclockwise until it loosens up. Some disposals might need a special tool from the manufacturer.
3. Carefully hold and lower the disposal unit, then set it aside. Heads up—it can be pretty heavy, so you might want a hand.
4. Under the sink, take off the mounting assembly by unscrewing the bolts or screws.
5. Push the old sink flange up through the drain hole and pull it out.

Step 3: Apply new plumber’s putty

1. Clean up the area around the sink drain hole, getting rid of any old putty or gunk.
2. Grab a good chunk of plumber’s putty and roll it between your palms to make a rope about as thick as a pencil.
3. Press the putty around the underside rim of your new (or cleaned-up old) sink flange.

Step 4: Reinstall the flange

1. Pop the sink flange back into the drain hole, pressing down firmly to get a nice seal.
2. Under the sink, slide the mounting assembly back over the flange.
3. Evenly tighten the mounting bolts to lock the flange in place. Don’t go overboard—overtightening can warp the flange or sink.
4. Up top, wipe away any extra plumber’s putty that oozed out around the flange.

Step 5: Reattach the garbage disposal

1. Hoist the garbage disposal back up, lining it up with the mounting ring.
2. Turn the mounting ring clockwise to lock it in.
3. Reconnect the drain pipe, tightening the nuts snugly.
4. Reattach the dishwasher hose if you’ve got one, making sure the clamp’s tight.
5. Plug the disposal back in or flip the circuit breaker back on.

Step 6: Test for leaks

1. Run some water into the sink and peek underneath to see if there are any leaks around the flange or connections.
2. Flip on the garbage disposal and check again while it’s running.

If it’s all dry down there, give yourself a pat on the back—you just replaced your sink flange!

We’re here to help

Dealing with a leaky garbage disposal doesn’t have to be a nightmare. With some elbow grease, you can fix it yourself and save some cash. If you need parts, advice, or a helping hand, AppliancePartsPros.com is here for you.

Keep in touch for more tips and updates. Follow us on Facebook and Twitter. Got questions or need some one-on-one help? Don’t hesitate to reach out. We’re here to make your DIY repair journey as smooth as possible.