Chevrolet 2007 Optra Owner's Manual page 275

How to Add Coolant to the Coolant
Surge Tank
Notice: This vehicle has a specific coolant fill
procedure. Failure to follow this procedure
could cause your engine to overheat and
be severely damaged.
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is
visible but the coolant level is not between the
Minimum and Maximum marks, add a 50/50 mixture
of clean, drinkable water and proper coolant at
the coolant surge tank, but be sure the cooling
system, including the coolant surge tank pressure
cap, is cool before you do it. See Engine Coolant on
page 268 for more information.
If no coolant is visible in the surge tank, add
coolant as follows:
CAUTION:
{
Steam and scalding liquids from a hot
cooling system can blow out and burn
you badly. They are under pressure, and if
you turn the coolant surge tank pressure
cap — even a little — they can come out at
high speed. Never turn the cap when the
cooling system, including the coolant
surge tank pressure cap, is hot. Wait for
the cooling system and coolant surge
tank pressure cap to cool if you ever have
to turn the pressure cap.
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