Oldsmobile 1997 Aurora Owner's Manual page 238

3. Then fill the coolant surge tank with the proper mix,
up to FULL COLD.
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 fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mix to the coolant surge tank
until the level reaches FULL COLD.
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