Defective Sink Flange

• 1). Shut off the main water supply to the house if the sink does not have a separate water supply valve. The water main is typically located either in an adjacent room or in the basement near the water heater.
  
  
• 2). Loosen the slip nut that is connected to the sink trap with channel lock pliers. The slip nut helps attach the sink trap to the main drain line in the wall. Remove the nut, and gently pull down on the sink trap and take it off the pipe.
  
  
• 3). Remove the slip nut attaching the sink drain pipe to the sink drain with channel lock pliers. Disconnect the stopper mechanism by turning the screw on it counter-clockwise with your fingers, which will release the stopper mechanism.
  
  
• 4). Remove the retaining nut connecting the sink drain to the sink with a pipe wrench. Pull out the sink drain and scrape off any remaining plumber's putty with a putty knife. Inspect the sink flange, and if it is damaged or worn, replace it.
  
  
• 5). Form a thin line of plumber's putty by rolling it in your hands. Place the plumber's putty on the bottom side of the sink drain flange. Push the sink drain back into place. Replace the retaining nut to the sink drain below the sink with channel lock pliers.
  
  
• 6). Cover any exposed pipe threads with three layers of plumber's tape. Replace the pipes in the order you removed them. Tighten the slip nuts with channel lock pliers.
  
  

Defective Drain Pipes

• 1). Shut off the main water supply to your home before beginning any work.
  
  
• 2). Remove the slip nut securing the sink trap to the wall pipe with channel lock pliers. Pull off the drain pipe from the sink drain, and lift out the drain assembly from the sink.
  
  
• 3). Cover any visible threads with plumber's tape. Push a slip nut onto the untapered end of the new tail piece and the threaded portion of the nut facing outward. Attach the tailpiece or straight pipe to the sink drain, and tighten the slip nut with the channel lock pliers.
  
  
• 4). Push the two slip nuts on each end of the new sink trap pipe. Attach the sink trap to the main drain line in the wall, and the slip nut will secure the sink trap.
  
  
• 5). Connect the opposite end of the sink trap to the tail piece, and attach the sink trap to the tail piece by tightening the slip nut with channel lock pliers.