Our server is on 10.3.1. Our locators are located in a folder, I right click them in Catalog and select Rebuild, then right click the Composite one and go to Share As>Geocode Service, and overwrite the existing service on our server. I haven't had any issues with it, and I update at least monthly. Eventually, I would love to script it and have it run automatically once a month. Is your service hanging on the starting/stopping? Were you rebuilding it another way?