What You Need to Know Before Starting

Replacing a Badger 5 garbage disposal takes two to four hours and requires turning off power at the breaker, not just at the switch. The Badger 5 is a 3/4-horsepower unit made by InSinkErator, and the replacement process involves disconnecting the old unit from the sink flange, drain line, and electrical box, then installing a new one in reverse order. You do not need a plumber for this job if you are comfortable working under a sink and following a step-by-step sequence.

The most common mistake is forgetting to turn off the circuit breaker before you start, which can cause serious injury. The second most common mistake is not supporting the old disposal as you loosen it, so it drops and damages the sink or your hands. A third mistake is cross-threading the mounting ring when you install the new unit, which creates a leak that shows up days later.

Key Takeaways

  • Turn off power at the circuit breaker before you touch anything under the sink, and test the disposal switch to confirm power is off.
  • You will need a bucket, adjustable wrench, screwdriver, plumber's putty, and a helper to support the old disposal as you disconnect it.
  • The mounting ring holds the disposal to the sink flange and must be loosened in a specific order to avoid cross-threading the new unit.
  • The drain line and electrical connection come off last, and the new disposal goes in by reversing the removal steps in exact reverse order.
  • Test for leaks by running water for one minute before you call the job complete, because some leaks only show up under water pressure.

Gather Your Tools and Materials

Before you go under the sink, collect everything you need in one place. You will need an adjustable wrench (8 to 10 inches), a screwdriver (flathead and Phillips), a bucket or shallow pan to catch water, plumber's putty, a flashlight or headlamp, and a helper to hold the old disposal steady while you work. If you do not have plumber's putty, you can buy it at any hardware store for a few dollars.

Check that your new Badger 5 unit is the same voltage as your old one (usually 120 volts) and that you have the mounting hardware that came with it. The new disposal should come with a mounting ring, rubber gasket, and fiber ring. If any of these pieces are missing, do not start the job—return the unit and get a complete one. Having a second person under the sink with you is not optional; the old disposal weighs 8 to 10 pounds and will drop if you try to hold it and loosen bolts at the same time.

Turn Off Power and Drain the Line

Locate your home's electrical panel and find the circuit breaker labeled for the kitchen or garbage disposal. Switch it to the OFF position. Go back to the sink and flip the disposal switch up and down three times to confirm there is no power. If the disposal makes any sound or movement, you have the wrong breaker—go back and find the correct one.

Place a bucket under the P-trap (the curved pipe under the sink) and loosen the slip nuts on both ends with your adjustable wrench. The water will drain into the bucket. Once the water stops, you can remove the P-trap completely and set it aside. This step prevents water from spilling all over you when you disconnect the disposal.

Disconnect the Old Disposal from the Sink Flange

Look up at the sink flange (the metal ring that holds the disposal to the sink opening). You will see three bolts arranged in a triangle around the flange. These bolts are part of the mounting ring, which sits below the sink. Using your adjustable wrench, loosen each bolt one-quarter turn in a rotating pattern—loosen the first bolt a little, then the second, then the third, then back to the first. Do not fully remove one bolt before moving to the next, because the mounting ring will tilt and jam.

Once all three bolts are loose enough to turn by hand, have your helper hold the disposal steady from below while you continue turning the bolts. The disposal will start to drop as the bolts come out. Keep your hands clear of the mounting ring as it spins—it can pinch your fingers. Once the bolts are fully removed, the mounting ring will fall away and the disposal will be free from the sink.

Disconnect the Drain Line and Electrical Box

With the disposal now loose, you can disconnect the discharge tube (the pipe that comes out of the side of the disposal and connects to the drain line). This connection is usually held by a hose clamp or a slip nut. Use your wrench or screwdriver to loosen it, then slide the tube off. Water may drip, so keep your bucket nearby.

Next, locate the electrical box on the side of the disposal. You will see a knockout (a removable metal disc) with a cable running into it. Loosen the cable connector nut by turning it counterclockwise with your wrench. Once it is loose, pull the electrical cable out of the box. Do not touch the wires inside the box. Now the old disposal is completely free and can be lifted out and set aside.

Install the New Badger 5 Unit

Before you install the new disposal, clean the sink flange with a damp cloth to remove any old plumber's putty or debris. Roll a rope of fresh plumber's putty about the thickness of a pencil and press it around the underside of the sink flange. This creates a watertight seal between the sink and the new mounting ring.

Position the new disposal directly under the sink flange and align the three bolt holes. Have your helper hold the disposal in place while you insert the three bolts through the mounting ring and into the flange. Tighten the bolts in the same rotating pattern you used to loosen the old ones—a quarter turn on each bolt, moving around the triangle. Tighten until the mounting ring is snug against the sink, but do not over-tighten, which can crack the sink or strip the bolts.

Reconnect the Drain Line and Electrical Box

Slide the discharge tube back onto the outlet of the new disposal and tighten the hose clamp or slip nut. Make sure the connection is hand-tight plus one-quarter turn with your wrench—tight enough to seal, but not so tight that you cannot loosen it later if you need to.

Now reconnect the electrical cable. Feed the cable into the electrical box on the new disposal and tighten the cable connector nut by turning it clockwise with your wrench. The cable should not move when you tug on it. Reconnect the P-trap by sliding the slip nuts back onto the pipes and tightening them with your wrench. Hand-tight plus one-quarter turn is the right amount of tension.

Test for Leaks and Confirm Operation

Before you call the job complete, turn the circuit breaker back on and test the disposal. Flip the switch and listen for the motor to start. Let it run for 10 seconds, then turn it off. Now run water from the sink for one full minute while watching under the sink for drips. Check the P-trap connection, the discharge tube connection, and the area around the mounting ring. If you see any drips, turn off the water and tighten the connection that is leaking by one-quarter turn with your wrench, then test again.

Once the disposal runs without leaking, you are done. The job is complete and the new Badger 5 is ready to use. If a leak appears days later, it is usually because the mounting ring was not tightened evenly or the plumber's putty was not pressed firmly enough around the flange. You can fix this by loosening the three bolts slightly, re-pressing the putty, and re-tightening in the rotating pattern.

Frequently Asked Questions

Can I replace a Badger 5 with a different brand of disposal?

Yes, but the mounting ring and bolt pattern may be different. Most disposals use a similar three-bolt mounting system, but the size and spacing vary. Before you buy a replacement, measure the distance between the bolt holes on your sink flange or bring a photo to the hardware store. InSinkErator disposals are usually compatible with each other, but mixing brands sometimes requires a new mounting ring.

What if I cannot loosen the mounting bolts?

explore a penetrating oil like WD-40 to the bolts and wait 15 minutes for it to soak in. Then try again with your wrench. If a bolt still will not budge, you may need a longer wrench for more leverage, or you may need to tap the wrench gently with a hammer to break the bolt loose. Do not force it hard enough to strip the bolt, or you will have to drill it out.

Do I need to hire an electrician to reconnect the power?

No, if the old disposal was hardwired into an electrical box under the sink, you can reconnect the new one yourself by feeding the cable into the box and tightening the connector nut. If your old disposal was plugged into an outlet, straightforward plug the new one in. If you are uncomfortable working with electrical connections, a licensed electrician can do this step for $75 to $150.

How long does it take to replace a Badger 5?

Two to four hours for a first-time replacement, depending on how tight the old bolts are and whether you run into unexpected problems like a stuck discharge tube. If you have replaced a disposal before, you can do it in 90 minutes. Budget extra time if the old unit is corroded or if you need to make a trip to the hardware store for supplies.

What should I do with the old disposal?

Take it to your local recycling center or scrap metal facility, which will accept it for free or a small fee. Some hardware stores also take old appliances for recycling. Do not put it in the trash, because it is too heavy and takes up space in the landfill. If you cannot transport it yourself, ask your trash collection service whether they pick up large appliances on bulk collection day.