Jeff I normally spray some Contact Cleaner on the plunger shaft and drum make sure all the fingers are making good contact with the drum and are not bent or worn, use a pencil eraser on the drum to clean the contact surfaces. You need some special tools to disassemble the E Unit and that can be a little tricky. If the fingers need to be replaced I would suggest you locate someone in your area that has done that before as changing the Fingers and desoldering the wires is a little bit tricky if you have never done it before. There is a tool for opening up the E Unit bracket and removing/replacing the Fingers and another for holding the bracket together during the process.