A roller cone drill bit having a bit body with at least one support arm extending from the bit body. Each support arm may have an associated spindle extending inwardly. A respective cone assembly may be rotatably disposed on each spindle. At least one diverter plug may be disposed in a hole formed in each support arm. A void space may be formed between one end of each diverter plug and the bottom of the associated hole. At least one fluid flow passageway may extend from the surface of the associated support arm to the void space to allow communication of fluid containing debris with the void space. Rotating action of the roller cone drill bit and associated cone assemblies may force packing of debris into the void space which results in biasing the diverter plug outwardly from the associated hole to contact adjacent portions of the associated cone assembly.