Mercury Mariner 8/9.9HP 4-Stroke Factory Service Manual, Page 204Get this manual
Water Pump Cover Reassembly 1Apply Special Lubricant 101 to O.Dof seal and seal surface2Install seal into cover3Place water tube guide onto seal
Impeller and Pump Cover Installation
1Install neoprene washer2Install drive keyUse 2-4-C wTeflon to hold key to drive shaftIMPORTANT: It is recommended that the impeller be replaced regardless of appearanceIf impeller must be reused, it must be installed in the direction of original rotationInstalling impeller with vanes reversed from their previous "set" will result in vane breakage shortly after unit is returned to service3Install new impeller and align with drive key4Install neoprene washer5Lubricate I.Dof water pump cover with 2-4-C w Teflon6Install cover on drive shaft and while pushing down on cover, rotate drive shaft CLOCKWISE and install cover over impeller