Oldsmobile 1999 Alero - Manual (Page 209)

yellow blue
5-15
NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. So
use the recommended coolant.
CAUTION:
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.
1. You can remove the coolant surge tank pressure cap
when the cooling system, including the coolant surge
tank pressure cap and upper radiator hose, is no
longer hot. Turn the pressure cap slowly
counterclockwise (left) about two or two and
one
- half turns. If you hear a hiss, wait for that to
stop. This will allow any pressure still left to be
vented out the discharge hose; wait for that to stop.