SEI MARINE PRODUCTS- Mercury Mariner Impeller Kit 47-89981Q1 3.9 4 4.5 6 7.5 8 9.8 HP 1975-1986 with .456 O.D. Shaft This impeller kit replaces OE#: 47-89981Q1 and fits 3.9-9.8 HP Mercury and Mariner outboard lower units from 1975-1986. Fits Units with .456 O.D. Shaft.