The oil in the "bath" is the oil sitting in the bottom of the base of the filter. This oil holds larger pieces of debris, such as leaves and insects, that drop into it due to the abrupt change in direction of the airflow. The air, now only contaminated with finer particles, goes through the mesh to remove them. The particles stick to to the oil treated mesh.
Some styles of oil bath use metal mesh, others use fiber mesh. Some filters called oil bath filters don't actually have a bath. They just have the oil treated mesh through which the air passes as it enters the carburetor.
Last edited by Otto Skorzeny; 02/03/2023 1:27 PM.
