Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 259Get this manual
IMPORTANT: When using an impeller whose blades have taken set, face the curl of the blades in counterclockwise directionDO NOT install the impel lerwilh its blades oriented in reversed direction from original rotation, or premature impeller failure will occur3Assemble the water pump impeller onto the drive shaft and down over the keyApply light coat of 2-4-C Marine Lubricant (92-90018A12) to the inside of the pump coverPosition the water pump body over the drive shaft and water pump locating pinsRotate the drive shaft in clockwise directionwhile pushing down on the water pump body to ease the water pump over the impeller blades 52725 Waler Pump Impeller Waler Pump Impeller Key