Have a Coleman brand generator thats probably twenty years old if not more. Runs great, but its leaking oil from the crankshaft seal. I need to get the generator out of the way, but can't figure out how to get the rotor off the shaft. I tried a puller, but it felt like it was going to break the end of the rotor (the part where the brushes make contact at the end) because its some sort of composite. Any ideas here? I snapped a few pics, any help would be great, thanks!