We unstop lots of urinals. We use the urinal auger by Rigid, but lots of Plumbing supply stores have them. The chemical that i used earlier in my career is called Clobber. It will eat through all that hair,gum and shit, but dont pour it in the urinal if water is sittin in it or it will splash back on you and burn you. To be sfe I would call a drain cleaning company in your area and let them clean/unstop that line. We usually charge $50.00 to unstop a urinal in my area.
ClogCleaner