Sierra 18-3207 Impeller Kit for Mercury Marine Engines Sierra 18-3207 Impeller Kit is an aftermarket replacement kit for Mercury Marine engines. All Sierra marine parts are manufactured to meet or exceed OEM requirements. For Use On Engine Models 30 1271884 - 1448139 30 Jet C159200 - G589999 35hp 1217222 - 1448139 35hp 1571114 - 1960826 35hp 1960827 - 6445652 35hp 6445653 UP 40hp 2874704 - 4362214 40hp 4362215 - 4860102 40hp 2 cyl 4860103 - 6445653 40hp 4 cyl C159200 UP 45hp 5531630 UP 50hp 1