1993 Buick Century Owner's Manual - Page 203

All Cooling Systems A CAUTION: Adding only plain water to your c.ooling system can be dangerous. Plain water, some other or liquid like alcohol, can boil before the proper coolant mix will. Your vehicle's coolant warning systemis set for the proper coolant mix. With plain water or the wrong mix, your engine could get too hot but you wouldn't get the overheat warning.Your engine could catch fire and youor others could be burned.Use a 50/50 mix ofclean water and a proper antifreeze. I I A CAUTION: You can be burned you spill coolant on hot if engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough.Don't spill coolant on a hot engine. I 201