1996 Buick Roadmaster Owner's Manual - Page 244

Checking Coolant 'hrning the surge tank pressure cap when the engine and radiator are hot can allow steam and scalding liquids to blow out and burn you badly. Never turn the surge tank pressure capeven a little when the engine and radiator are hot. -- -- When your engineis cold, the coolant level should be at the FULL COLD mark. The surge tankis in the engine compartment, directly behind the battery. If this light comes on, it means you're low on engine coolant. LOW COOLANT LEVEL See "Low Coolant Light" in Index. the ' 6-22