What are the installation instructions for replacing the motor and rubber boot in the roof-mount solar powered fan (Model SC8BL)?

Disconnect the solar panel wiring, loosen the three motor bracket screws, and remove the six dome arm screws from the roof side to get access to the fan blade.
Remove the fan blade from the motor shaft. The motor and donut should slide out from the top where the new motor and donut can go in its place.
Reverse the process.
A 3/8″ socket or box/open end wrench will be needed for the hex heads and a 5/16″ box/open end wrench for the square head set screw on the solar fan blade (it's not the Allen head set screw used on the other fan blades).

See Installation Instructions.