Buick RIVIERA 1993 Manual page 234

Adding Coolant
The engine coolant
recovery tank is located at
the left of the engine
compartment.
To Check Coolant:
When
your engine is cold, the
coolant level should be at
"FULL COLD," or a little
higher. When your engine is
warm, the level should be
up to "FULL HOT," or a
little higher.
To Add Coolant: If
you need more coolant, add the
proper mix at the coolant recovery
tank.
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