Turn off the electrical power to your dishwasher from the kitchen circuit breaker and turn off the water-supply valve below your sink.
Remove the screws from the bottom toe panel using a screwdriver, then lift up the panel to remove it from the dishwasher.
Disconnect the drain hose from the pump motor in the center of the unit, then remove the bolts holding in the motor using an adjustable wrench.
Disconnect the wires from the motor. Turn the motor and lift it out of the dishwasher.
Hold the motor shaft and then pull up the cutter blade. Lift up and remove the grater and stainless steel ring.
Turn the fan counter-clock wise and lift it up to remove it. Remove the shaft seal below the fan.
Insert the new shaft seal onto the motor shaft and the place the fan back over the new seal. Turn the fan clockwise to lock it into place.
Reinsert the stainless steel ring, grater and cutter blade onto the shaft. Place the motor back into the dishwasher and reconnect the wires to the motor.
Reinsert the bolts into the motor to hold it in, then reconnect the drain hose to the motor.
Place the toe panel back in place and reinsert the screws. Turn the water supply valve on and turn on the electrical power from the circuit breaker.