1995 Buick Century Owner's Manual - Page 183
1995 Buick Century Manual
Page 183 highlights
How to Add Coolant to the Coolant Recovery Tank I you haven't found a problem yet, but coolant level f the isn't at ADD, add a 50/50 mixture of clean water (preferably distilled) and a proper antifreeze the coolant at the recovery tank. (See "Engine Coolant" in Index for more information about the proper coolant mix.) NOTICE: Engine damage from running u r engine p without coolant isn't covered by your warranty. If there seems to be no leak, with the engine on, check to see if the electric enginefan is running. If the engine is overheating, both fan(s) shouldbe running. If it isn't, your vehicle needs service. 5-17