1997 Buick Regal Owner's Manual - Page 256

If the overheat warning continues, there's one more thing you can try. You can add the proper coolant mix directly to the radiator, but be sure the cooling system is cool before you do it. a Steam and scalding liquids fromhot cooling system canblow out and burn you badly. They are under pressure, and you turn the radiator if pressure cap even a little they can come out at high speed. Neverturn the cap when the cooling system, including the radiator pressure cap, is hot. Wait for the cooling system and radiator pressure cap to if you ever have to cool turn the pressure cap. -- -- You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and itwill burn if the engine parts are hot enough. Don't spill coolant on a hot engine. When the coolant in the coolant recovery tank is at the COLD mark, start your vehicle. 5-20