If you brought a generator to the watchtower or to the bunker, but still cannot install it, please note that first it has to be fully assembled at your home base as well as radio, gunsmith bench, chopper and other similar objects that are crafted in two stages. After you complete crafting the generator at your home base, pick it up with both hands and fix it on the luggage rack of your motorcycle and deliver to the watchtower (or to the bunker).