Sink leaking? I bet the gasket in the sink strainer is leaking. This is a DIY plumbing repair I did at a friend's restaurant, but the concept is the same. But if you need to fix your leaking chef kitchen sink, this is how to repair a leaking sink.
For this sink, which is a bit more industrial than your average sink, you remove the top ring from inside the sink. For most household sinks, there is a ring with tabs on it that attaches the sink strainer to the sink itself. For either type, you can buy a fancy tool to remove the ring, or you can use my favorite tools, a hammer and a screwdriver.
First remove the pipe that is connected to the strainer - this is called a tailpipe, btw. Tap on the tabs under the sink to move the ring counterclockwise. You might have to jam a screwdriver into the basket from the top to keep it from spinning. If you break the tabs, its ok, you can go buy a new sink stainer for cheap, and its shiny clean too.
Remove the the strainer, and clean it and the sink surfaces. There may be old plumber's putty around the hole in the sink. Pick up a new gasket at your local hardware store, it will be a rubber gasket that also comes with a cardboard ring. If you are using the old sink strainer and there was plumber's putty on it or the inside part of the hole in the sink, roll out a long hot dog of plumber's putty about ¼' in diamter, and wrap this around the sink strainer and place the sink strainer back in the hole. Press down on strainer to squish out excess putty.
From underneath, place the rubber gasket onto the strainer, then the cardboard ring, then screw on the metal or plastic ring. For this restaurant kitchen sink, its a little backwards, but you get the idea. Screw the ring on tight, but don't break the ring getting it tight.
Re-attach the tailpipe - the piece of pipe that connects the sink to the drain pipes- and fill the sink with water, and check for leaks. If it leaks, you may be able to just tighten up the ring a bit, if that doesn't work, it may be that the sink hole is warped or has some crud in it that is not letting the gasket seal tight. You'll have to take it apart, clean up the hole, and re-assemble.
Have you done some DIY plumbing repair? Let us know below: