I've never had to replace the foam. If you felt inclined you could probably use felt. The spring inside the silver plunger often becomes clogged with dried goop. You can use Triflow and a hair dryer to get it moving. The motor is not fun to disassemble, just take photos as you go. And replacing the gear is not for faint of heart. Most Berninas I've ever worked on look just like the photos-very clean. Do not put any grease on the nylon gears. They didn't use grease on them at the factory and they shouldn't be greased now.