Chevrolet 2007 Corvette Owner's Manual page 357

3. Fill the coolant surge tank with the proper
mixture until the level inside stabilizes at
the FULL COLD mark on the front of the
surge tank.
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.
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