2006 Chevrolet Corvette Owner's Manual - Page 315

5. Then replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated. Check the level in the surge tank when the system has cooled down. If the coolant is not at the proper level, repeat Steps 1 through 4, then reinstall the pressure cap. If the coolant is not at the proper level when the system cools down again, see your dealer. 4. With the coolant surge tank pressure cap off, start the engine and let it run until you can feel the upper radiator hose getting hot. Watch out for the engine cooling fan. By this time, the coolant level inside the coolant surge tank may be lower. If the level is lower, add more of the proper mixture to the coolant surge tank until the level stabilizes at the FULL COLD mark on the coolant surge tank. 5-39