2003 PONTIAC BONNEVILLE coolant

Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans
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.
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.
See
Engine Compartment
Overview on page
5- 14 for
more information on
location.
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The coolant level should be at or above the FULL COLD
mark when the engine is cold. The coolant level
should be at the FULL HOT mark under normal
operating conditions.
If it isn’t, 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
syster
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.
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
1
Heater and radiator hoses, and other engine radiator corrosion may result.
-In addition, the engine
parts, can be very hot. Don’t touch them. If you coolant will require change sooner - at 30,000 miles
(50 000 km) or 24 months, whichever occurs first.
do, you can be burned.
Damage caused by the use of coolant other
Don’t run the engine if there
is a leak. If you than DEX-COOL@ is not covered by your new vehicie
run the engine,
it could lose all coolant. That warranty.
could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the
vehicle.
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How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t at the FULL COLD mark, add a
50/50 mixture of
clean, drinkable water and DEX-COOL@ engine coolant
at the coolant recovery tank. See
Engine Coolant on
page
5-26 for more information.
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. 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 mixture. 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.
When the coolant in the coolant recovery tank is at the
FULL
COLD mark, start your vehicle.
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If the overheat warning continues, there’s one more
thing you can
try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system
is cool before you do it.
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 radiator
pressure cap
-- even a little -- they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap,
is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
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How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise until
it first stops. (Don’t press down while turning the
pressure cap.)
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, but now push
down as you turn it. Remove the pressure cap.
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3. Remove the 3800 Series II V6 engine cover shield
to access the bleed valve.
3.1. Clean the area around the engine oil fill tube
and cap before removing. Twist the oil
fill
tube, with cap attached, counterclockwise
and remnvc! it^
3.2. If you have the supercharged engine,
remove the nut in the center of the cover
shield.
3.3. Lift the engine cover shield at the front, slide
the catch tab out
of the engine bracket and
remove the cover shield.
3.4. Put the oil
fill tube, with cap attached, in the
valve cover oil
fill hole until you’re ready to
replace the cover shield.
4. After the engine cools,
open the coolant air
bleed valve. There
is one bleed valve. It is
located on the
thermostat housing.
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5. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler
neck. See
Engine Coolant on page 5-26 for more
information about the proper coolant mixture.
If you see a stream of coolant coming from an air
bleed valve, close the valve. Otherwise, close
the valve after the radiator is filled.
6. Rinse or wipe any spilled coolant from the engine
and the compartment.
5-38
7. Replace the 3800 Series II V6 engine cover shield.
7.1. Remove the oil fill tube, with cap attached,
i.2. Insert the catch tab on the cover shield
under the bracket on the engine.
from the
valve cover.
7.3. Place the hole in the cover shield over the
hole in the valve cover. Install oil
fill tube and
cap by twisting clockwise.
7.4. If you have the supercharged engine, install
the nut in the center of the cover shield.
8. Then fill the coolant recovery tank to the
FULL
COLD mark.

9. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap
off.
11. By this time, the coolant level inside the radiator
filler neck may be lower.
If the level is lower, add
more of the proper
DEX-COOL@ coolant mixture
through the filler neck until the level reaches
the base
of the filler neck.
12. Then replace the
pressure cap. At any
time during this
procedure
if coolant
begins to
flow out
of the filler neck,
reinstall the
pressure cap.
IO. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans. Be
sure the arrow on the pressure cap lines
up like this.
5-39