Instructions
Climb the ladder next to the office that Patrick told you about in MySims Agent. The control box for the crane will be on the right and once you approach, you will be able to select "Repair."
Connect the wires from the generator to the big box. Place the large gear at the bottom of the three small gears to the right on the screen. Put a small gear beneath the two gears near the top middle.
Connect everything with the three pulleys and the MySims crane will work.