Chevrolet 2000 Lumina Owner's Manual page 201

CAUTION:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can injure you. Keep hands, clothing and tools
away from any underhood electric fan.
If the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down.
When the engine is cold, the coolant level should be at
or above the COLD mark on a cold engine. The coolant
level should be at or above the HOT mark on a hot
engine. If it isn't, you may have a leak in the radiator
hoses, heater hoses, radiator, water pump or somewhere
else in the cooling system.
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