Step 3 · Clean the Shower Arm Threads
Once the old shower head is removed, inspect the exposed male threads on the end of the shower arm. Use a small, stiff-bristled brush (an old toothbrush works well) or a rag to carefully remove any old, shredded plumber's tape, plumber's putty residue, or mineral scale. For stubborn buildup, you can use a cloth dampened with a calcium/lime remover. A clean, smooth threading surface is essential for creating a new, watertight seal with the diverter.