Cooper is a compulsive licker but he doesn't lick himself... he licks ME. I've tried to break him of it but have been unsucessful with the exception of training him to stop when he hears "that's enough". He'll stop for 10 seconds then resumes the licking party.
Did anything in the house change before he started licking himself? Changing his food, cleaning products you use in the house, your shampoo, his shampoo ... anything like that can cause anxiety that would lead to behavior like that. My cat has an anxiety problem and will "cover up" things - imaginary and not - when something changes in our house.
Also, have you checked him for fleas? That could be it. Or a skin irritation. You might want to give him a bath using an oatmeal shampoo and see if that makes a difference. If it does, you would probably want to go to the vet and see if there's a skin irritation causing the licking.
Or he could be just a crazy chi licking machine. Redirecting him is your best bet but I don't know how well that will work... it doesn't work on mine