A shower arm can leak at either the shower head's end or the end going into the wall. Below you will find directions on how to tackle both leak problems associated with a leaking shower arm.
Step 1 - Turn Off the Water
Turn off the water supply to your shower. Depending on the type of plumbing your home uses, you will either turn the water off at a tap leading into the shower or turn the main water shutoff to the house.
Step 2 - Wrap Duct Tape Around the Shower Arm
Wrap a rag or duct tape around the arm close to the shower head. The tape protects the shower head from damage when you remove it.
Step 3 - Remove the Shower Arm
To remove the shower head from the shower arm, use a vise grip, slip-joint pliers or a pipe wrench to turn it counterclockwise. Place another pipe wrench on the protected portion of the shower arm in a direction that would cause it to turn in a clockwise direction. You do this to hold the shower arm in place with one wrench and turn the head with the other wrench. If you are having trouble removing the shower arm, lubricate it with penetrating oil on the threads of the arm.
Step 4 - Clean the Shower Arm
Now clean the threaded area of the shower arm with a rag or a brass wire brush.
Step 5 - Wrap With Nonstick Tape
Wrap the clean threads with some nonstick tape. Wrap tightly in a clockwise direction, about 3 to 5 turns, and cover the threads. This step prevents further leaking from the connection between the shower arm and the shower head.
Step 6 - Install the Shower Head
Install the shower head onto the shower arm. Turn it in a clockwise direction until tight. You don’t need to over-tighten when you use nonstick tape; it seals quite well. Turn on the water at full force through the shower head to see if it leaks between the arm and the head. If it does, tighten the head a little more until it stops. An indication of the shower arm leaking in the wall connection is the evidence of water stains or leaks.
Step 7 - Slide the Trim Ring Back
Slide the trim ring back away from the wall, down the shower arm, and toward the shower head. If the trim ring doesn’t move, carefully insert a knife between the wall and ring and cut the caulking around it. You should be able to look along the arm through the hole in the wall with the aid of a light. If you see water stains or actual water droplets, this is the source of the leak.
Step 8 - Spray Penetrating Oil
Before attempting removal, spray some penetrating fluid on the threads and let it soak for a while.
Step 9 - Remove the Ear Elbow
Use 2 pipe wrenches on the shower arm directly opposite each other like a tee handle, 1 pushing up and the other pulling down. Turn the arm counterclockwise out of the drop ear elbow. Position the wrenches as close to the wall as you can.
Step 10 - Replace the Internal Ear Elbow
The internal ear elbow is usually the cause for most of the leaks. You can replace this with a simple piece of piping. Usually 0.5-inch pipe works well. Solder the piece together and reinstall the shower arm.