Do you have a stinky machine? There are potentially two culprits to a smelly machine. The first source could be old grease on your upper and lower steel gears. They need to be cleaned and new grease added. Another source is the Oil Drip Pan Felt Liner. Over the decades, the Felt Liner collects spare oil and grease from the belly of your machine. That is the main purpose of the liner to protect the pan. It also traps odors, mold and mildews. Think about how old these machines are and how we used to smoke in our homes, etc. Maybe the machine lived in a humid climate. Most of the machines that come through our service department have NEVER had a new felt liner. We recommend changing these pads annually to avoid the collection of excessive oils, grease, and odors. Please specify 221 or 222 for the proper felt liner size.