Disclosed is a seal assembly for a grading machine. The grading machine may include a machine body, a blade assembly, and a circle assembly supporting the blade assembly. The circle assembly may include a circle having a plurality of gear teeth. The grading machine may also include a drawbar assembly connecting the circle assembly to the machine body. The seal assembly may include a non-metallic seal component extending circumferentially around an inner circumference of the circle assembly for sealing the plurality of gear teeth.