DEAR TIM: My wife has been fighting with a stinky garbage disposal. It's relatively new (I replaced it for other reasons last year). She's tried many different approaches to cleaning, and yet to her the smell returns. Before I pop the drain pipe and see if there's something accumulating down there, do you have any tips for cleaning a garbage disposal? Leo N., Seattle, WA

DEAR LEO: This is pretty simple to solve but because you now have an odor problem, it is going to take a little work. Let me explain what has probably happened over time. The inside surfaces of the garbage disposal get a slime on them because I suspect the disposal is not being used properly.

Many people simply throw garbage down into a garbage disposal, turn it on while some water is running through it and quickly turn the disposal off as well as the water. The spinning motion of the disposal blades throws a slurry of garbage up on the sides of the disposal chamber and the small amount of water coming from the faucet doesn't always completely wash this organic slurry off the sides of the disposal.

If this slurry of organic debris is not completely washed off the inside of the disposal, it begins to rot and this decomposition produces a foul gas. If you do this enough times - meaning not rinse off the organic slurry, it can harden over time and then becomes a problem to clean. You have to re-hydrate the hardened slurry.

The proper way to run a garbage disposal, in my opinion, is to put the garbage in it and grind it up with a strong stream of water running from the faucet. Once you have finished grinding all of the garbage, immediately place the stopper in the large hole at the bottom of the sink and fill the sink with water. As the water is filling the sink, add a generous squirt of liquid dish soap. Fill the sink at least 2/3 the way with water.

Once the sink is filled with this soapy water, immediately remove the stopper from the sink and quickly turn the disposer back on. If you could see inside your disposal, you would see a wild vortex of action.

Because the sink was filled with water, the inside of the disposal fills with water the instant you remove the stopper. The spinning blades of the disposal agitate this soapy water inside the disposal and this completely washes the sides and all parts of the disposal.

There is another bonus benefit to this rinsing operation. The actual drain pipe leaving the disposal and all downstream pipes get thoroughly flushed. Often kitchen drain pipes and the plumbing branch line that connects the sink to the main plumbing drain line leaving your home get clogged with the slurry produced by a garbage disposal. People simply do not let water run long enough after the garbage is ground up.

If you don't let perhaps a gallon of water run in the sink after the garbage disposal makes that high-pitched noise telling you the garbage is gone, the slurry of organic debris is not carried completely out of your house. It can take 30 or 40 seconds of running water to fill a gallon container. My guess is you rarely run the water that long.

To remove any hardened food slurry deposits from the inside of your garbage disposal, you are now going to have to do a small amount of plumbing work. Go to a real plumbing supply house and purchase a rubber test cap that has a stainless steel tightening band on it. This clamp is just like a muffler band clamp. Plumbers use these temporary test caps to close off the ends of pipes for either water or air pressure testing required by a plumbing inspector.You should be able to find one made for 1 and 1/4 inch diameter PVC schedule 40 pipe that will fit perfectly on the 1 and 1/2 inch diameter tubular pipe leaving the disposal.

Disconnect the pipe that leaves the disposal from the drain system piping under your sink or from the p-trap under the sink. Attach the rubber test cap to the end of the tubular pipe leaving the garbage disposal and tighten the clamp. Place an empty five-gallon bucket under the end of this pipe in case the clamp leaks or slips.

With the rubber test cap in place, start to fill the disposal with very warm water. If you purchased the right clamp and you have the clamp tightened just right, the disposal will act as if it is clogged and the water will begin to back up into the sink. Stop running the water as soon as the level reaches the top of the chrome strainer basket in the bottom of the sink that connects to the disposal.

Now add one-half cup of powdered oxygen bleach to the garbage disposal filled with water. Oxygen bleach is non-toxic and will not harm you, the garbage disposal, the plumbing system or septic tank should your home be connected to one.

Once the powder is added to water it begins to create millions of tiny oxygen ions that start to soften and attack the rotten, hardened garbage on the sides of the disposal and any slurry on the side walls of the drain pipe leaving the disposal. The oxygen bleach solution, if left in the disposal for up to an hour, does a fantastic job of sanitizing the unit.

After letting the oxygen bleach solution work inside the disposal for an hour, loosen the clamp on the rubber test cap and let the water rush into the bucket. Reconnect the disposer to the plumbing drain system and perform the same operation as described above as if you had just ground up some garbage. In other words, insert the stopper into the sink, fill the sink with warm, soapy water, remove the stopper and turn on the disposer.

Once you have done this, the disposer should be as clean as the day it was installed. It should also smell as good as the day it was installed!

Some people have tried placing ice cubes in a smelly disposal to clean it. The problem is you can't be sure the chips of ice will clean off all of the hardened slurry.

If the disposal is smelly, you are going to have to clean it the right way just once. After that, if you rinse it thoroughly after each use, it will never give you a problem. An odor problem that is!

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Author's Note: I received the following tip from Julian L. not too long ago. I thought it was a good addition to this column and am happy to share it with you. Thanks, Julian. TC

In 2007, my InSink Erator garbage disposal developed a severe blockage, which I  attempted to fix as follows.

STEP ONE:
Thinking that I had loosened the motor enough from the disposal's bottom with a 1/4" Husky Allen Wrench, which is definitely more effective than a regular one (with a small handle), I did the following.

1. Depressed disposal's bottom pushbutton.
2. Inserted and locked disposal's magnetic cover.
3. Flipped disposal's wall switch to on.

Subsequently, I heard some spinning but the motor soon stopped. Although I hadn't succeeded, I felt good knowing that the motor was still alive.

STEP TWO:
I then realized that the blockage was still there.  With power off, I continued turning the motor in both directions repeatedly with the wrench until I felt that the motor was turning relatively freely.  To me, the wrench is a great tester because it tells me whether a blockage is still present or not, major or minor.

STEP THREE:
Suddenly, I thought of using WATER PRESSURE to help overcome the residual blockage as follows.

1. Ensured disposal's wall switch was off.
2. Inserted and locked disposal's magnetic cover.
3. Stored plenty of cold water in sink.
4. Depressed disposal's bottom pushbutton.
5. Flipped disposal's wall switch to on.

The disposal now started to spin and continued spinning! It still worked after I had turned the power off and back on.

CONCLUSION:
Gist of my idea: I use water pressure to re-enforce and sustain the motor's initial spinning. In a very difficult case, it is this re-enforcement that ensures the unclogging. No matter how bad the clogging is, one can always create enough water pressure to overcome the clogging (by storing enough water in the sink prior to running the motor). The principle of my idea applies to other disposal brands also.

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Message from Tim: Years ago while researching a column about cleaning decks, I discovered the wonders of Oxygen Bleach. It is perhaps the 'greenest' cleaner I know of as it uses oxygen ions to break apart stains, dirt and odor molecules. There are no harsh chemicals, and it works on just about anything that is water washable. I decided to create my own special blend using ingredients made in the USA. In fact, the raw materials in the active ingredient are food-grade quality registered with the FDA. I call my product Stain Solver. I urge you to use it to help with cleaning your garbage disposal. You will be amazed at the results!

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