2003 OLDSMOBILE AURORA cooling

Notice: When adding coolant, it is important that
you use only DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL@ is added to
the system, premature engine, heater core or
radiator corrosion may result.
In addition, the engine
coolant will require change sooner
-- at 30,000 miles
(50,000 km) or 24 months, whichever occurs first.
Damage caused by the use of coolant other
than DEX-COOL@
is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half
DEX-COOL@ coolant which won’t damage
aluminum parts.
If you use this coolant mixture,
you don’t need
to add anything else. Adding
a plain water
to your cooling
system can be dangerous. Plain water, or
some other
liquid such as aicohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system
is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others
could be burned. Use a
50/50 mixture of clean,
drinkable water and DEX-COOL@ coolant.
Notice: If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty. Too much water
in the mixture can freeze
ana crack ihe engine, raiiiaiur, bakr
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice: If you use the proper coolant, you don’t
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
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Coolant Surge Tank Pressure Cap
The cooling system pressure cap is located on the
surge tank.
Notice: Your cooling system pressure cap is a
pressure-type cap and must be tightly installed to
prevent coolant
loss and possible engine damage
from overheating.
Engine Overheating
You will find a coolant temperature gage on your
vehicle’s instrument panel. Your Driver Information
Center (DIC) will also display messages about engine
overheating. See
Engine Coolant Temperature Gage on
page 3-38.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message HOT STOP
ENGINE is displayed, an overheat
protection mode which alternates firing groups of
cylinders helps prevent engine damage. In this mode,
you will notice a
loss in power and engine performance.
This operating mode allows your vehicle to be driven
to a safe place in an emergency. Driving extended miles
(km) and/or towing a trailer in the overheat protection
mode should be avoided.
Notice: After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded. Repair the cause of coolant
loss, change the oil and
reset the oil life system. See “Engine
Oil” in the
Index.
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Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Surge Tank with Pressure Cap
S. Two Electric Engine Cooling Fans
I
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.
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If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.
A low coolant level should be indicated by a LOW
ENGINE COOLANT message on the Driver Information
Center.
If it is, you may have a leak at the pressure
cap or
in the radiator hoses, heater hoses, radiator,
water pump or somewhere else in the cooling system. Heater
and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is a leak. If you
run the engine,
it could lose all coolant. That
could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the
vehicle.
If there seems to be no leak, with the engine on, check
to see
if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running.
If they aren’t, your vehicle needs service.
Notice: Engine damage from running your engine
without coolant isn’t covered by your warranty.
See “Overheated Engine Protection Operating
Mode’’ in the Index for information on driving to a
safe place
in an emergency.
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Notice: When adding coolant, it is important that
you use only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or radiator corrosion may result. In addition, the engine
coolant will require change sooner
- at 30,000 miles
(50 000 km) or 24 months, whichever occurs first.
Damage caused by the use of coolant other
than DEX-COOL@
is not covered by your new vehicle
warranty.
How to Add Coolant to the Coolant
Surge Tank
If you haven’t found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn’t at or above the
FULL COLD fill
mark line (4.5 inches (1 1 cm) from the top of the filler
neck), add a
50/50 mixture of clean, drinkable water and
DEX-COOL@ coolant at the coolant surge tank, but be
sure the cooling system, including the coolant surge tank
Coolant on page 5-24 for more information.
If no coolant is visible in the surge tank, add coolant as
follows:
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Steam and scalding Ii ids 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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1 Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the proper coolant mixture.
CAUTION: (Continued)
I I
With plain water or the wrong mixture, your
engine could get too hot
but you wouldn’t get
the overheat warning. Your engine could catch
fire and you or others could be burned. Use a
50/50 mixture of clean, drinkable water and
DEX COOL@ coolant.
Notice: In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant
IT-:-’=- e.
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.
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1. Park the vehicle on a level surface. 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 one-quarter turn and
tnen stop.
If you hear a hiss, wait for that to stop.
A hiss
means there
is still some pressure left.
2. Then keep turning the
pressure cap slowly,
and remove
it.
3. Then fill the coolant
surge tank with the
proper mixture, to the
FULL COLD fill
mark line (4.5 inches
(1 1 cm) from the top of
the filler neck).
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4. With the coolant surge tank pressure cap off, start
the engine and let
it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower.
If the level is lower, add
more of the proper mixture to the coolant surge
tank until the level reaches about
4.5 inches
(1 1 cm) from the top of the filler neck.
5. Then replace the pressure cap. Be sure the arrow
on the pressure cap lines up like this.
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