This sealing brush fits into the radiator cowl of a grain harvester. It closes the gap between the cowl and the hood or chassis, directing airflow through the radiator core rather than allowing it to escape around the edges. A worn or missing brush allows debris ingress and reduces cooling efficiency by permitting recirculated hot air to re-enter the intake path. The brush is constructed as a continuous strip of bristles held in a rigid carrier that mounts to the cowl perimeter. When reinstalling, ensure the bristles contact the opposing surface evenly along the full length to maintain the seal.