Please do NOT spray your bird with anything but fresh, clean water unless explicitly instructed to do so by an avian vet!
Seeing as you have had your bird so long and the plucking is a recent development, I would strongly suggest getting him in to see an avian specialized vet soon. Unless there have been any major life changes recently (such as spending less time with him, a new pet, moving to a new home etc...), happy, healthy, well adjusted parrots don't just start plucking at random. There are numerous medical reasons (such as a food allergy, heavy metal poisoning, infection, fatty liver disease etc...) that only a vet who specializes in birds can correctly diagnose. I see you live in California, where there are fortunately many avian specialized vets. Do a search in your area and get him in to see one ASAP.