If the source is not a connection from above then your disposal needs to be replaced. Try cupping your hands around the very top under the sink while running water. The ring that seals the gasket turns clockwise to tighten. The only other repairable leak would be where the piping comes out the side. There can also be a smaller dishwasher drain hose above that.
Garbage disposals can range from $70 on the low end to $380 on the high end -- and generally speaking, you get what you pay for. A less expensive unit is likely to produce more noise, require more water, and clog more easily than a higher-end model. Likewise, a more expensive unit will be faster, quieter and less likely to malfunction than a lower end model -- and it will be lighter-weight and offer greater capacity as well. The average cost of a garbage disposal installation with a one-year manufacturer’'s warranty is $185. The average amount of time taken to install a garbage disposal, including cleanup, is three hours. The hourly cost for labor will range from $20 to $40 -- $28 on average.
Knowing the difference between what can go down the disposal and what should go into the trash can save you an emergency call to the plumber. This is especially pertinent during the holidays when the kitchen is filled with people and the sink with dirty dishes. Practice these three everyday maintenance tips to help you maximize the lifespan of your garbage disposal.
The first official use of the word dates from 1735, when a royal decree authorised the establishment of eight gambling houses in Naples. The word is likely a blend, or portmanteau, of "capo" (boss) and a Neapolitan street game, the "morra".[3][5] (In this game, two persons wave their hands simultaneously, while a crowd of surrounding gamblers guess, in chorus, at the total number of fingers exposed by the principal players.)[6] This activity was prohibited by the local government, and some people started making the players pay for being "protected" against the passing police.[3][7][8]
I thought that this might be underpowered (my last one almost had double the power, after all), but it has plenty of power to eat through whatever you throw at it. I don't dump EVERYTHING down the drain, but it takes what I give it with no problems. And the last garbage disposal was loud and raucous--yes, raucous. But this one is a pleasure. When you flip the switch, it makes a reassuring hum. It sounds more like a fine piece of machinery than a couple of animals fighting to the death inside my sink (like my old disposer).
The mounting bracket for your new garbage disposer assembles by inserting the fiber gasket, back-up flange and mounting ring over the sink flange, in that order. Be sure to hold these three pieces in place while you insert the snap ring over the flange. It’s called a snap ring because you’ll hear it snap in place. Then firmly tighten the three mounting screws against the backup flange, being careful to tighten them evenly.
We hate to say it, but stoppages in garbage disposals are generally due to “operator error”. Either we have put too much in at one time or tried to force something through, smashing it with a spoon (there is that pesky spoon again!). Pasta, rice and salad are killers of garbage disposal drains and really need to be put down the drain in small amounts; if you put half a pot of rice in at the same time you definitely stand the change up plugging up the pipes under your sink.
Lay the disposal on its side under the sink so you can make the electrical connections. Make sure the circuit breaker is off. Remove the plate on the bottom of the disposal to expose the wiring and use wire connectors to connect the wires from the disposal to the matching wires from the power supply. Finally, secure the power cord to the bottom of the disposal using the proper connection. Replace the plate to cover the wires. (See Fig 6)
You should first find out whether only the disposal is broken, or if the power has gone out completely in the areas near your kitchen sink. Try resetting the circuit breaker that leads to the kitchen, or replacing a fuse if you have an older electrical box. If the garbage disposal makes no noises at all when you flip the switch, you might also want to check under the sink to see that it’s plugged in.

Garbage Disposal Install