1997 Chevrolet Corvette Owner's Manual - Page 229

How to Add Coolant to the Coolant Surge Tank If you haven't found a problem yet, but the coolant level isn't at the FULL COLD mark, add a 50/50 mixture of clean water (preferably distilled) and DEX-COOL@ coolant at the coolant surge tank, but be sure the cooling system, including the coolant surge tank pressure cap, is cool before you do it. (See "Engine Coolant" in the Index for more information.) I Steam and scalding liquids from a hot cooling system can blow out andburn you badly. They are under pressure, and if you turn the coolant surge tankpressure cap even a little they can come out at high speed. Never turn the cap when the cooling system,including the coolant surge tankpressure cap, is hot. Waitfor the cooling systemand coolant surge tank pressure cap tocool if youever have to turn the pressure cap. -- --