1997 Buick Park Avenue Owner's Manual - Page 249

6. Start the engine and let it run until you can feel the upper radiator hose getting hot. Watch out forthe engine fans. 7. By this time, the coolant level inside the radiator filler neck may be lower. Ifthe level is lower, add more of the proper DEX-COOL@coolant mixture through the filler neck until the level reaches the base of the filler neck. 8. Then replace the pressure cap. At any time during this procedure if coolant begins to flow out of the filler neck, reinstall the pressure cap. Be sure the arrows on the pressure cap lineup like this.