Buick 2003 Century Owner's Manual page 250

You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
I
I
3. After the engine cools, open the coolant air bleed
valves.
4. Fill the radiator with the
proper DEX-COOL@
coolant mixture,
up to the base of the
filler neck. See
Engine Coolant on
page 5-22 for more
information about the
proper coolant mixture.
5. if you
see
a stream of cooiani coming from an air
bleed valve, close the valve. Otherwise, close the
valves after the radiator is filled.
6. Rinse or wipe any spilled coolant from the engine
and the compartment.
There are two bleed valves. One is located on the
thermostat housing. The other is located on the
ihermostat bypass tube.
5-33