How to Replace a Garbage Disposal – Part 5

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I’m ready now for the final Waste King L-8000 Garbage Disposal garbage disposer installation. Recall the Waste King® was temporarily mounted in Part 3 of this series to fit the plumbing connections and is now just hanging in the “supported” position on the mount ring. In Part 4 the electrical outlet was installed to plug in the power cord. Now I’ll install the sink flange, mount the new unit, connect the waste arm and plug-in the new garbage disposer. This project is continued from How to Replace a Garbage Disposal – Part 4.

I begin the final installation by swinging the waste arm plumbing out of the way as shown for unobstructed access to remove the disposer, having loosened the slip joint nuts on the waste tee.

Waste King Legend 8000 Garbage Disposal Installation

Waste King Legend 8000 Garbage Disposal Installation

Install the Garbage Disposal Sink Flange

After dismounting the garbage disposer from the mount ring, I unscrewed the support ring and took out the sink flange.

The rim of the sink flange is packed with a generous bead of plumber’s putty for a watertight seal against the sink drain.

Garbage Disposer Sink Flange Packed with Plumber's Putty

Garbage Disposer Sink Flange Packed with Plumber’s Putty

Insert the sink flange into the sink drain hole and press it down with even pressure to seat it until the plumber’s putty just begins to squeeze out around the rim.

Install the Garbage Disposer Sink Flange

Install the Garbage Disposer Sink Flange

Position the anti-friction fiber gasket on the support ring and thread the support ring on the sink flange. Note the Up arrow printed on the support ring for correct orientation.

Attach the Garbage Disposer Fiber Gasket and Support Ring to the Sink Flange

Attach the Garbage Disposer Fiber Gasket and Support Ring to the Sink Flange

The plumber’s putty will squeeze out as the support ring is tightened, pressing the sink flange against the drain hole. Slowly tighten the support ring, pausing a few seconds between turns to allow the putty to squeeze out. You’ll feel when the flange is fully seated against the sink and support ring is stays tight with no more “give” as the putty squeezes out.

Look for an even squeeze out of the plumber’s putty like this photo to ensure there are no gaps or voids between the flange and sink bottom.

Plumber's Putty Squeeze Out around the Garbage Disposer Sink Flange

Plumber’s Putty Squeeze Out around the Garbage Disposer Sink Flange

Use the edge of the putty knife to trim away the excess plumber’s putty:

Trim the Excess Plumber's Putty from the Sink Flange

Trim the Excess Plumber’s Putty from the Sink Flange

Install the Waste King Sink Mount

Orient the mount ring and cushion mount as shown and attach it to the sink flange. Work the inner groove of the cushion mount over the lip of the sink flange.

Install the Waste King EZ Mount Support Ring and Cushion Mount

Install the Waste King EZ Mount Support Ring and Cushion Mount

Inspect the cushion mount to verify it’s installed correctly on the sink flange. Note how the inner beveled edge is seated evenly against the flange.

Waste King Garbage Disposer Cushion Mount Correctly Installed

Waste King Garbage Disposer Cushion Mount Correctly Installed

Mount the Waste King Garbage Disposer

Align the Waste King hopper projection and mount ring slot so it will slide into the mount ring when you raise it up. The Waste King is a bit on the heavy side at ~14 lbs and you’ll be working in an awkward position reaching inside the cabinet, so proper initial alignment will minimize the effort.

Position the Waste King Garbage Disposer for Mounting

Position the Waste King Garbage Disposer for Mounting

Lift the Waste King into the mount ring and set it in the “Supported” position. Check the unit alignment such that the discharge elbow is pointing where you want it to meet the waste arm plumbing.

Twist the mount ring until the hopper projection is in the “Lock” position. Take care not to turn the disposer unit, only turn the mount ring. I found it not too difficult to twist the mount ring with my thumbs on the mount ring ears. You can tap the ears with a hammer if needed until it’s locked.

If you need to realign the garbage disposer, loosen the mount ring first so as not to twist the sink flange which will break the seal with the plumber’s putty.

Waste King Garbage Disposer EZ Mount in the Locked Position

Waste King Garbage Disposer EZ Mount in the Locked Position

Connect the Waste Arm to the Discharge Elbow

Swing the waste arm around to the disposer discharge elbow, adjust the telescoping slip tube and insert the discharge elbow into the waste arm plumbing. Check the slip joint washers and tighten the slip joint nuts on the elbow, telescoping arm and waste tee joints.

Attach the Garbage Disposer Waste Arm to the Discharge Elbow

Attach the Garbage Disposer Waste Arm to the Discharge Elbow

Check that the disposer on/off switch by the sink is off.

Plug the power cord into the electrical outlet.

Garbage Disposal Splash Guard

Press the rubber splash guard into the disposal drain.

Insert the Splash Guard into the Garbage Disposal Drain

Insert the Splash Guard into the Garbage Disposal Drain

Leak Check and Operation Testing

Run the water for a couple of minutes and check all the plumbing connections and sink flange for leaks.

Insert the stopper, fill the sink with several inches of water, let is stand for around 15 minutes while checking the flange for leaks under the sink.

  • If you have a leak, unplug the power cord,  check and tighten the slip joint connections.
    If the slip joint continues to leak, make sure the slip washer is installed correctly and/or
    replace the plastic slip washer.
  • If the leak is coming from the sink flange, tighten the sink flange if you feel some “give”.
    Worst case, you may have to remove the sink flange and repack it with plumber’s putty.

Turn on the disposal switch, run the water and listen to the motor run. You’ll hear a loud click (this is normal) as the grinders swing into position.

Garbage Disposal Installation - Check for Leaks

Garbage Disposal Installation – Check for Leaks

Waste King Legend 8000 Product Review

I’ve had the Waste King Legend 8000 for a month now. My thoughts are:

  • The #1 Rating by Consumer Reports (August 2009) greatly influenced my purchase decision.
  • The Lifetime In-Home Service Warranty is unbeatable. The lifetime warranty is printed right
    on the box and not buried in fine print. All you need is the original purchase receipt for warranty service.
    Consumer Reports convinced me there was no catch for this high-end quality product.
  • Compared to my old 1/3 HP disposer, it’s much quieter – you can have a normal conversation while it’s running.
  • The 1 HP motor effortlessly ground up everything we put in it.
  • I really liked the EZ Mount system because it was sturdy and assembled without tools or complicated parts.
  • I’m glad I removed the old 3-bolt mount & sink flange because:
    • The plumber’s putty beneath the old flange was dried and brittle, and eventually would have leaked.
    • Reusing the old 3-bolt mount with the optional Waste King 3-bolt mount adapter isn’t worth the risk
      of having dried out plumber’s putty if your old disposer is several years old.
    • The extra effort of removing the old 3-bolt mount and cleaning the old putty only took 15 minutes. I therefore
      can’t imagine why you’d want to keep the old mount; or at least reinstall it with fresh putty.
  • The plug-in power cord is a better way to go in my opinion and installing the electrical outlet under the sink was no problem.
    • Removing the Waste King will much quicker when I install a new instant hot water dispenser.
  • The unit is a bit on the large and heavy side, but that’s due to the 1 HP motor, and a minor consideration only
    during installation. The “supported” position on the mount ring means you can hang the disposer
    to take the weight off your arms while adjusting the plumbing alignment. This is a nice feature for the

Take care,

Bob Jackson

Copyright © 2019   Reproduction strictly prohibited.


  1. Richard P. January 1, 2012 at 7:49 pm - Reply

    Thanks so much for an excellent tutorial on replacing an ISE disposal with the Waste King L-8000. The photos were a great and they answered all my questions. I wasn’t sure about replacing the sink flange and old three-bolt hanger, but it turned out to be a breeze. Thank you.

  2. Brian July 4, 2012 at 3:07 pm - Reply

    You saved me a ton of time and money! I had a leaking disposal that I installed 2 years ago. Well you forget how you did it and I pulled your tutorial since it’s a Wasteking model (I have the 2600) but identical and followed the steps exactly (also replaced the gasket going to the main drain and a new clamp for the dishwasher) works like a charm! Thanks!

  3. Dustin July 21, 2012 at 1:42 am - Reply

    Wow. Thank you so much for the tutorial. We purchased our house in 2009 which came with a Waste King that I can only assume, based on looks, was installed when the house was built in the 80s. I also purchased the Waste King 8000 from Amazon after pricing out similar models in Canadian retailers for 3 to 4 times that amount. It seems we all have the same hang ups about the EZ mount system and the need to add a receptacle under the sink but your tutorial makes so much sense and the pictures are great. Now if only there was a 24HR Home Depot around here. Thanks again.

  4. Dave K November 27, 2012 at 3:15 am - Reply

    As you pointed out, it’s better for the outlet to be a bit higher so water cannot run down the cord and into the outlet. So my question is at what height did the outlet end up at once you mounted it? I’m mounting an outlet beneath the sink and was thinking of the required outlet height so it won’t be too low once all the cabinets and sink are installed.

    • Bob Jackson November 27, 2012 at 1:01 pm - Reply

      The bottom of the receptacle box is 12 inches above the bottom of the kitchen cabinet. I set the outlet box at 12 inches because:
      1) It’s the same height as measured from the finished floor to the bottom of the general wall receptacles in my home.
      2) The outlet placement was high enough that access isn’t obstructed by the plumbing.
      3) Most importantly, it was sufficiently high to guarantee a “drip loop” in the garbage disposal electrical cord.

      To my knowledge, there isn’t a specific height required the National Electrical Code (NEC). You can contact your local Building Dept. to ask if there are local building code requirements. See this link for more information: What is the proper height to mount a switch or receptacle?

      Thanks for reading!

  5. Davis January 13, 2013 at 10:03 pm - Reply

    Thanks, this was incredibly helpful! A wonderful walk-through.

  6. John January 14, 2013 at 12:02 pm - Reply

    Hi Bob – very nice tutorial, great explanations and excellent photos. I’m about to install the same disposer, and this confirms I’m on the right track.

    You commented:

    “I’m glad I removed the old 3-bolt mount & sink flange because:
    The plumber’s putty beneath the old flange was dried and brittle, and eventually would have leaked.
    Reusing the old 3-bolt mount with the optional Waste King 3-bolt mount adapter isn’t worth the risk
    of having dried out plumber’s putty if your previous disposer was several years old.
    The extra effort of removing the old 3-bolt mount and cleaning the old putty only took 15 minutes. I therefore
    can’t imagine why you’d want to keep the old mount; or at least reinstall it with fresh putty.”

    The reason I plan to use the adapter kit is that we just renovated our kitchen a year ago, and we installed a fairly expensive brushed nickel sink flange with an extended tailpiece that was needed for installing a disposal in our fireclay farmhouse sink, and which matches the faucet. I don’t want to install the cheaper looking shiny chrome flange included with the Waste King. Since the renovation was only a year ago, I don’t think dried out putty will be an issue. I did a test assembly using the adapter last night, and I think it should work quite nicely.

    Thanks again for posting the tutorial.


    • BobJackson January 14, 2013 at 6:17 pm - Reply

      > Since the renovation was only a year ago, I don’t think dried out putty will be an issue.
      You’ll be fine with the recently installed sink. My sink was over 10 years old so reworking the sink flange with fresh putty was a probably a good decision.

      Thanks for reading!

  7. Susan April 9, 2013 at 7:36 pm - Reply

    Thank you so much, this was great. I had exactly the same situation, replacing a 19 year old Badger which was installed when our house was built. I had already decided on the waste king 8000 from Amazon. Your instructions, step by step, and recommendations for parts and tools were spot on. Not only saved the cost of a plumber, but also the cost for the electrician to install the outlet.

  8. Jason May 13, 2013 at 12:35 pm - Reply


    I just replaced our Badger5 with the WK 8k (over the weekend) and I can’t be more proud, thank you for the great instructions!!

    I do have one question about the WK 8k though, now that it’s in place and working. When we cut it on, then engine causes it to move slightly. At first it was enough movement to rotate the mount and sink collar, but now that it’s settled in I’ve not see that happen. I’m just wondering if this is suppose to be by design with the easy lock system or do I need to re-look at how I’m supporting it?

    • BobJackson May 13, 2013 at 4:54 pm - Reply

      The start-up engine torque should not cause the unit to move or twist. Recommend checking the support ring is tight. I’m guessing the sink flange relaxed as the plumber’s putty squeezed out a little more, which relieved the clamping force of the support ring against the bottom of the sink; hence the wiggle on start-up.

      Your question made me curious and I just checked the support ring tightness on my Waste King 8000: after 2.5 years it needed about 3/4 turn to re-tighten it, but the sink flange hasn’t moved nor has there been a leak.

  9. Bill June 14, 2014 at 7:43 pm - Reply

    Bob thanks so much for the detailed instructions. You saved this DIY guy lots of money!! I replaced my crappy Badger 9 Insinkerator with the waste king 8000 and it only took me 90 minutes. This is the first plumbing task I’ve ever tried. I didn’t even really use the manual I basically followed your steps. Thanks again!!

  10. Russell July 17, 2014 at 7:43 pm - Reply

    Can a disposal be installed into a fireclay sink? Read somewhere that fireclay sinks are not strong enough and they may crack when installing the disposal. Has anybody here installed a garbage disposal to a fireclay Risinger sink? If so, which garbage disposal works? Bought the extra deep flange recommended by the manufacturer but it doesn’t seem to fit the hole.

    Thanks for any advice you can give me.

    • Bob Jackson July 17, 2014 at 9:15 pm - Reply

      Best to ask your sink manufacturer. The discussion at this link may be helpful.

  11. DBenson November 12, 2014 at 2:33 pm - Reply

    I am replacing my garbage disposal this week. I have a romex wire coming out of my wall under the sing straight into the current disposal. I have a switch on my breaker and I have turned it off.

    Can I just wire the cable into my new disposal without using a 3 prong power cord that comes with the Waste King? I know I will probably have to disconnect the 3 prong cable out of the Waste King.

    I am going to get a Waste King also but don’t have a outlet under my sink, just the romex wire coming out into the disposal from behind the wall. Not sure if it is a safety concern or convenience concern to add the outlet like you did.


    • Bob Jackson November 12, 2014 at 5:44 pm - Reply

      > Can I just wire the cable into my new disposal without using a 3 prong
      > power cord that comes with the Waste King?
      Doing so will probably void the warranty. It might be possible although I’ve not tried it and don’t recommend it. The factory power cord might be attached with screw terminals or it could be crimped or soldered connections which would be unsuitable for attaching NMB-14/2 Romex cable.

      Since your NMB-14/2 Romex cable exits the wall it should be a simpler job than mine was to mount and wire a metal junction box and receptacle. No need for the aluminum flex conduit in your situation.


      • DBenson November 12, 2014 at 10:02 pm - Reply

        You said metal, could I use a plastic blue box or the reason for not doing that is because water could get into it? Also, could I just use a 20amp single outlet instead of a 15amp outlet?

        • Bob Jackson November 13, 2014 at 8:01 am - Reply

          Neither metal and plastic boxes are waterproof. The advantage of a metal box is it can (and must) be grounded; that way if it should get wet and cause a short circuit the box won’t be “hot” or energized. Best to always have a path to ground that’s lower resistance than your person. I prefer metal boxes for new work and it’s easy to surface mount a metal outlet box to the wall. I use plastic boxes for old work when cutting a hole in the drywall for interior mounting. Check the Electrical projects on this site or use the search box for numerous examples of each box.

          If you have a 15Amp circuit breaker use a 15Amp rated receptacle and at least NMB-14/2 (14 gauge) cable for the pigtail connections. A 20Amp breaker requires a matching 20Amp rated receptacle and NMB-12/2 (12 gauge) cable. The Romex house wiring coming out of wall under the sink should be marked 14/2 or 12/2.

          • DBenson November 13, 2014 at 11:01 am - Reply

            This is great information. I picked up a single 20amp outlet and the same metal box you have and cover. I am looking at my circuit breaker and guess what? 15amp… awesome now I have to go back to the store to get a 15amp single outlet.

          • DumbQuestionDave January 19, 2015 at 8:35 pm - Reply

            Hi Bob – This 5-part series is great information and thanks to you I have almost worked up the courage to replace my girlfriend’s burnt-out insinkerator with a waste king. However, I want to make sure I understand the electrical part (part 4) completely. The current unit is hardwired and it is the white-jacketed romex coming straight from the wall, just like DBenson mentions. I notice you say the flex conduit can be skipped, and then mention that the metal box is preferable because it can and must be grounded. Now for my absolutely dumb question – connecting the romex ground wire to the outlet and then the outlet to the steel box is all I need to do to ground it, correct?

            • Bob Jackson January 20, 2015 at 4:12 pm - Reply

              > connecting the romex ground wire to the outlet and then the outlet to the steel box is
              > all I need to do to ground it, correct?
              If you use a self-grounding outlet, correct. Most modern outlets with metal ears are self-grounding to the metal box, but verify it says so on the manufacturer’s labeling. Take care that a ground wire and ground screw connection is required to either the outlet or the metal outlet box.

              As I’ve wired the Leviton single outlet (see photo at the above link) the ground wire is connected to the outlet, and the outlet is grounding the metal junction box.

              You could also ground both metal box and the outlet with a pigtail connection as illustrated in this diagram. See the How to Wire an Attic Electrical Outlet and Light for details.

  12. HT March 1, 2015 at 1:16 pm - Reply

    Thanks so much! Your tutorial and photos probably saved me hours and were a great confidence boost that I could tackle this project. Waste King’s installation instructions were actually quite good, but I found this tutorial to be an excellent companion. Just installed the L1001 last night and everything seems to be in good working order.

  13. Della M Matthews December 8, 2015 at 2:13 pm - Reply

    Thank you , thank you the steps you gave on trouble shooting it was very helpful and I was able to get my garbage-disposal back working ,it was down for 3 weeks. I save money by using the 3 steps . My disposal now working again and I did this in 5 to10 minutes with a broom handle to unjam it.

  14. Maggi December 10, 2015 at 1:56 pm - Reply

    Thank you so much for the great tutorial! I’m in a similar situation with my old disposal being hard wired and the new one using a plug. The difference is that I have two sets of romex wires – one coming from the switch on the wall, the other running to a junction box in the basement below. Both have a set of black, white and ground wires. They were both connected to the old disposal, but I am unsure how to connect them all to the new single outlet. Can you help?

    • Bob Jackson December 12, 2015 at 10:58 am - Reply

      The wires that connected to old garbage disposal should be connected to the outlet in the same way. The outlet will be switch-controlled instead of the old hard-wired disposal. Identify each wire and label it with a small pieces of colored electrical tape. Now make a wiring diagram with pen and paper for the new outlet.

      I suspect the wires going to the basement junction box are the “line side” – meaning it provides power from the circuit breaker. I prefer to wire my switch controlled devices in this order:

      [circuit breaker] — [On/Off toggle switch] — [switch controlled outlet or light]

      My belief is your circuit is cabled as follows (not this is not a wiring connection diagram, rather a cable run order!):

      [circuit breaker] — [basement junction box] — [garbage disposal junction box under the sink] -[two (2) black wires for line & load]- [toggle switch]

      The key idea is the black/hot wire from the basement junction box goes directly to the toggle switch. Only the black/hot wire from the toggle switch is connected to the under-sink garbage disposal outlet. A bit more detail on this wiring point for the hot/black wiring only:

      [basement junction box] -line side black wire- [line side black/hot wire passes through the under sink junction box, probably a wire nut connection] -line side black wire- [toggle switch] -load side black wire- [load side black wire goes back to the under sink junction box] -load side black wire- [under sink outlet]

      Correct me if I’ve misunderstood your circuit layout. You can e-mail photos to bob[at], replace the [at] with the @ symbol.


  15. Bret M. December 12, 2016 at 2:09 pm - Reply

    Hi Bob. Thanks for your tutorial! It really helped this novice feel better about installing my 8000 which I just finished. The one thing I did different was that I did not use plumber’s putty because the instructions that came with the unit said to use the rubber sink flange gasket and fiber gasket when installing the unit onto a stainless steel sink.

    Another thing I found helpful in the instructions was that once the sink flange portion of the installation was done, to insert the stopper that came with the unit and fill the sink with water to check for leaks before proceeding with the rest of the installation. It would really be a pain to get everything done only to have a leak at the sink flange!

    Thanks again for your detailed instructions and I also appreciate that you actively answer questions we have so thoroughly.

    • Bob Jackson December 12, 2016 at 2:38 pm - Reply

      I don’t recall why I used plumber’s putty instead of the rubber flange gasket (lower right corner of photo). Both serve the same purpose but using the rubber gasket saves an extra trip to the hardware store to buy plumber’s putty. My Waste King 8000 has worked like a champ for 6 years now with no leaks.


  16. Ronnie March 3, 2017 at 10:22 am - Reply

    Hello…same situation here (except I bought a cheaper waste king disposal). But when I followed the steps my outlet won’t work! Here’s what I did (sorry for the long post but this is driving me crazy!)

    -I detached the wires going into my original garbage disposal. There were the usual three wires: neutral/white, hot/black, ground/copper. I didn’t realize this until later, but there were no wires coming from the light switch. Was there supposed to be a fourth wire from the switch?

    -I purchased a white, metal outlet box, and a GFCI 15 amp outlet with two receptacles. I connected the black wire to the brass screw, the white wire to the silver screw, and of course the copper wire to the green ground screw. I flipped the breaker, flipped on the light switch, and a lamp I plugged in would not power.

    -Since you used a non GFCI, i thought maybe that was the problem. So I went back out and bought a regular 15 amp outlet (still 2 receptacles). Still would not power anything. The outlets I used had two sets of screws and then the grounds crew. I noticed the second time around, I attached the wires to the bottom set of screws when the instruction said to attach the wires to the top set of screws. Either way, the outlet would not work.

    A few thoughts/questions…
    Should I have used a single outlet? I was going to at first like you did, but I could not find a 15 amp single outlet. They only had 20amp in single outlets. Should I have used the 20? None of the other outlets in the house that I can see are 20amps, so I was nervous about getting it.

    What about the wire from the light switch? The cable was coming directly from the basement and it was hardwired to the original disposal. I’m not sure where the light switch is wired to because it’s not visible under the sink. In your tutorial I didn’t see you do anything with a light switch wire. so I assume the light switch is wired behind the wall??

    Thank you for any help you can offer!

    • Bob Jackson March 4, 2017 at 10:51 am - Reply

      Did you have to flip a toggle switch (aka “light switch”) somewhere above to the kitchen counter to turn operate the old garbage disposal? If so, the disposal was hardwired to the switch like my old unit. My garbage disposal toggle switch is to the right side of the sink in this photo.

      Because I prefer a plug-in disposal the change I made was to install an outlet under the sink. The outlet is controlled by the same switch and wires.

      Original wiring:
      [circuit breaker] — [kitchen counter toggle switch] — [hardwired disposal]
      New wiring:
      [circuit breaker] — [kitchen counter toggle switch] — [under sink outlet] — [plugin disposal]


      RE: GFCI outlet.
      Did you check if the garbage disposal circuit was already protected by a GFCI circuit breaker or GFCI outlet somewhere in the kitchen? If you install a GFCI outlet on a branch circuit that’s already GFCI protected it will trip the new GFCI outlet, resulting in no power to everything on the load-side of the new GFCI outlet.

      RE: 20 AMP outlet
      A 20 AMP outlet on a circuit protected by a 15 AMP breaker is an electrical code violation. See NEC Table 210.21(B)(3).

  17. Elaine March 17, 2017 at 8:03 am - Reply

    Mr. Bob! Thank you so much, I was able to remove our garbage disposal, wire an outlet in and getting ready to put an instant hot water box under the sink. Slab Foundation and in winter it can take 4-5 minutes to get warm water. We are on a well so every drop is precious during droughts.

    These are the most easily understood directions with pictures I’ve come across!

    Kindest regards

  18. Sanjay August 19, 2018 at 4:31 pm - Reply

    Seems my problem is unique. So commenting here since the picture represents and similar to the setup to my issue (under the kitchen). I have cleaned every pipe however, when the garbage disposer is tuned on, water come up from the other side (second sink)? Even when the dishwasher drains, hear the bubble/water sound running into the sewer line? Can you help explain what is wrong.

    • Bob Jackson August 19, 2018 at 6:49 pm - Reply

      I need to see your drain configuration. Please e-mail pictures of the disposal and drain piping to bob[at], replace the [at] with the @ symbol.

      I suspect it’s a problem with the drain pipe arrangement, P-trap and/or the Drain Waste Vent (DWV).

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