What You Need to Know Before You Start

A Badger 5 garbage disposal installs under your sink in about an hour if you have basic plumbing tools and the right mounting hardware. The unit mounts to the sink drain opening using a three-bolt collar system, then connects to your drain line with a rubber coupling. You do not need to be a plumber—the job is mechanical, not electrical, and the hardest part is usually removing the old disposal if one exists.

Before you begin, turn off the power to your sink circuit at the breaker box and leave it off until the disposal is fully wired. Shut off the water supply under the sink. If you have an existing disposal, you will need to disconnect it first by loosening the mounting bolts and unbolting the drain connection. Clear out any standing water in the sink and have a bucket ready for drips.

Key Takeaways

  • The Badger 5 mounts using a three-bolt collar that screws onto the sink flange, and you must install the rubber gasket and mounting ring in the correct order or it will leak.
  • The drain outlet connects to your existing P-trap or drain line with a rubber coupling and hose clamp, which you tighten by hand first and then with a wrench.
  • The electrical connection is a straightforward plug into a standard outlet under the sink, or a hardwired connection if your sink has no outlet—do not attempt hardwiring yourself if you are unsure.
  • Test for leaks by running water for 30 seconds before you turn on the disposal, and check again after the first use.
  • The entire installation takes 45 minutes to an hour if you are replacing an existing disposal, or up to two hours if you are installing one for the first time.

Prepare the Sink Opening and Remove the Old Disposal

If you have an existing disposal, disconnect it first. Loosen the three bolts on the mounting collar underneath the sink using an adjustable wrench, turning counterclockwise. Once the bolts are loose enough, the disposal will drop slightly—support it with one hand so it does not fall and damage the drain line. Unbolt the rubber coupling that connects the disposal outlet to the P-trap or drain line by loosening the hose clamp with a screwdriver or wrench.

If the disposal is hardwired (connected directly to the electrical box rather than plugged in), do not touch the wires. Call a licensed electrician to disconnect it. Once the disposal is free, set it aside. Clean out any old putty or rubber gasket material from the sink flange using a plastic scraper or old credit card—do not use a metal tool, which can scratch the sink.

If you are installing a disposal for the first time and your sink does not have a disposal opening, you will need a plumber to cut one. This article assumes your sink already has the opening or you are replacing an existing unit.

Install the Mounting Hardware on the Sink Flange

The Badger 5 comes with a mounting assembly that sits on top of the sink flange. Lay out the parts in order: the rubber gasket (a flat rubber ring), the mounting ring (a metal ring with three tabs), and the three bolts with washers. The gasket goes first, directly under the sink flange, pressed up from underneath.

From above the sink, insert the mounting ring so its three tabs align with the three slots in the sink flange. The tabs should point outward. Push the ring down until it sits flat. From underneath, thread the three bolts through the holes in the gasket and into the threaded holes in the mounting ring. Hand-tighten all three bolts first, then use an adjustable wrench to tighten them in a crisscross pattern (bolt 1, then bolt 3, then bolt 2) so the ring pulls down evenly. Tighten until snug—do not over-tighten, which can crack the sink.

Attach the Disposal Unit to the Mounting Collar

The Badger 5 has a collar on top that screws onto the mounting ring. Align the three tabs on the collar with the three tabs on the mounting ring. Rotate the disposal clockwise by hand until the collar seats fully and the disposal hangs straight down. You should hear or feel a slight click when it locks into place. The disposal should not wobble or tilt.

If the disposal does not lock, rotate it back counterclockwise and check that the tabs are aligned. Rotate again slowly until you feel the collar engage. Do not force it—if it resists, the tabs are misaligned.

Connect the Drain Line with a Rubber Coupling

The outlet on the bottom of the Badger 5 is a threaded port. Your existing drain line (the P-trap or tailpiece) connects to it using a rubber coupling and hose clamp. Slide the rubber coupling onto the disposal outlet first, then slide it onto the drain line. The coupling should overlap both connections by at least half an inch on each side.

Tighten the hose clamp on the disposal side first by hand, then use a screwdriver or wrench to turn the clamp screw clockwise until it is snug. Do the same on the drain line side. Hand-tighten first so you can adjust the coupling if it is not aligned, then use a tool to finish. The coupling should not leak when water runs through it, but it will weep slightly if it is under-tightened.

Make the Electrical Connection

The Badger 5 comes with a three-prong plug. If your sink has a standard electrical outlet underneath (most modern installations do), straightforward plug the disposal into it. Make sure the outlet is on the same circuit as your sink light or a nearby counter outlet, and verify the breaker is labeled for that circuit.

If your sink has no outlet, or if the outlet is not in a convenient location, you have two options: install a new outlet (hire a licensed electrician) or hardwire the disposal directly to the electrical box (also hire an electrician). Do not attempt hardwiring yourself unless you are a licensed electrician. Improper wiring is a fire and shock hazard.

Once the disposal is plugged in, do not turn on the breaker yet. First, run water through the sink to check for leaks.

Test for Leaks Before First Use

Turn the water on at the supply valve under the sink. Let water run into the sink for 30 seconds and watch underneath for drips. Check the rubber coupling connection on both sides and the P-trap connection. A small amount of condensation on the outside of the pipes is normal, but actual water dripping means the hose clamp is loose.

If you see a drip, turn off the water, dry the area with a towel, and tighten the hose clamp another quarter turn with a wrench. Turn the water back on and check again. Repeat until the drip stops. Once the sink is dry and no water is running, turn the breaker back on and test the disposal by flipping the switch. Let it run for five seconds with no food in it, then turn it off.

Run water again for 30 seconds while the disposal is off, then turn it on and let it run for another five seconds. Turn it off and listen for any unusual grinding or rattling. A low hum and a slight vibration are normal. If you hear grinding that does not stop, turn off the disposal when ready and check for a foreign object inside.

Common Installation Mistakes to Avoid

The most common error is installing the rubber gasket upside down or forgetting it entirely, which causes leaks around the mounting collar. The gasket is slightly thicker on one side—the thicker side faces down, toward the drain. If you install it backwards, water will seep between the gasket and the sink flange.

Another frequent mistake is under-tightening the hose clamps on the drain coupling. Hand-tightening is not enough—use a tool to turn the screw until it is snug, but not so tight that you strip the screw. If the coupling leaks after you have tightened it, the coupling itself may be cracked or the drain line may not be seated fully inside it.

A third mistake is turning on the disposal before checking for leaks. Water running through the disposal will hide small drips, and by the time you notice a leak, water may have pooled under the sink and damaged the cabinet. Always test with the disposal off first.

Frequently Asked Questions

Do I need a special outlet for the Badger 5, or can I use any outlet under the sink?

Any standard 120-volt outlet works. It does not need to be a GFCI outlet, though many building codes now require one under the sink for safety. If your outlet is not GFCI-protected, ask an electrician to install a GFCI outlet or add a GFCI breaker to your circuit.

What if water leaks from the mounting collar after I install it?

The gasket is probably installed backwards or the bolts are not tight enough. Turn off the water, remove the three bolts, and check that the rubber gasket is seated correctly with its thicker side facing down. Reinstall and tighten the bolts in a crisscross pattern. If it still leaks, the gasket may be damaged and needs replacement.

Can I install a Badger 5 if my sink does not have a disposal opening?

No. Your sink must have a drain opening sized for a garbage disposal, usually 3.5 inches in diameter. If your sink does not have one, a plumber can cut one, but this requires special tools and may not be possible on all sink materials. Stainless steel and cast iron can be cut, but some composite materials cannot.

How tight should the hose clamp be on the drain coupling?

Tight enough that you cannot twist the coupling by hand, but not so tight that you strip the screw or crack the rubber. If you can turn the coupling with moderate hand pressure, it is too loose. If the screw spins without tightening, you have over-tightened and stripped it—replace the clamp.

What should I do if the disposal makes a loud grinding noise that does not stop?

Turn it off when ready. Something is stuck inside—usually a piece of bone, glass, or metal. Turn off the power at the breaker, wait 30 seconds, then use tongs or pliers to remove the object from the chamber. Never put your hand inside. If you cannot see or reach the object, call a plumber.