Mercury Impeller | Sierra 18-3052 Sierra 18-3052 Mercury Impeller Sierra 18-3052 Mercury Impeller Diameter 2 in. Depth 3/4 in. 6 blade Material: neoprene Drive: 3/4 in. brass ding Replaces Mercury 47-89982 Replaces Johnson/Evinrude 775462 Replaces Mallory 9-45311