Step 5 · Remove Dome Cap
With the handle removed, you will see a rounded or dome-shaped metal piece called the dome cap. This part is usually threaded. Grasp it firmly and turn it counter-clockwise by hand to unscrew it. If it's too tight, wrap a rag around it and use adjustable pliers to get a better grip and turn it loose. Lift it off to expose the plastic components and the cartridge retaining clip.