Things You'll Need
Allen key wrenches
New pipe nipple
Replacing a broken or outdated tub spout with a new Moen is a relatively simple task. Moen makes two different versions of tub spouts. Its iron-pipe size, or IPS, screws onto 1/2-inch male threaded pipe. Its slip-fit tub spout attaches to 1/2-inch copper tubing and is held in place with a hex-screw.
Remove the old tub spout. For slip fit tub spouts, look for the setscrew on the underside of the spout. Remove the setscrew with an Allen key wrench or with an appropriate screwdriver. Gently twist side to side until the copper pipe is free from the pipe connection. For IPS tub spouts, you will need to twist the old spout counterclockwise until it is free from the pipe connection. It may be necessary to use a pipe wrench to loosen severely corroded spouts.
Inspect the pipe connection for damage. Replace the section of pipe if it is corroded or too long or short. The piece of pipe that protrudes from the wall is called a nipple. You can purchase nipple sections inexpensively. Wrap both sides of the nipple with plumber's tape. Insert it into the wall fitting and caulk around the fitting.
Turn the slip-fit tub spout so that the cutout faces the ceiling. Gently tighten the setscrew using the enclosed 5/32-inch Allen wrench. Turn the spout clockwise until the cutout is facing down and looks centered. Tighten it down.
Screw an IPS onto the tub spout clockwise until the tub spout is centered correctly.