2003 Chevrolet Corvette Owner's Manual - Page 254

Checking Coolant Turning 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 cap - even a little - when the engine and radiator are hot. The vehicle must be on a level surface. When your engine is cold, the coolant level should be at the FULL COLD mark. The FULL COLD mark is on the front of the coolant surge tank. Don't overfill the surge tank. Too much coolant can result in an overflow when the fluid is hot. The coolant surge tank is located in the engine compartment behind the passenger's side headlamp. See Engine Compartment Overview on page 5-12 for more intormation on locatlon. 5-25