engine CHEVROLET IMPALA 2004 8.G Owners Manual

Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Engine Coolant Recovery Tank
B. Electric Engine Cooling Fans
C. Radiator Pressure CapA. Engine Coolant Recovery Tank
B. Electric Engine Cooling Fans
C. Radiator Pressure Cap
3400 V6 Engine
3800 V6 Engine
5-35

{CAUTION:
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.
The coolant level should
be at or above the COLD
mark on the coolant
recovery tank.To check the coolant level, look for the COLD mark on
the side of the coolant recovery tank that faces the
engine. When the engine is cold, the coolant level
should be at or above the COLD mark on the coolant
recovery tank. 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
system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them.
If you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
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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 is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
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 COLD mark, add a 50/50 mixture ofclean,
drinkable waterand DEX-COOL
®engine coolant at
the coolant recovery tank. SeeEngine Coolant on
page 5-29
{CAUTION:
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 would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
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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.
The coolant recovery tank is located in the rear of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12
{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. Do not spill coolant on a hot engine.
When the coolant in the coolant recovery tank is at the
COLD mark, start your vehicle.
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.
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How to Add Coolant to the Radiator
Notice:Your engine has a specic radiator ll
procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
The radiator pressure cap is located in the front of the
engine compartment near the diagonal cross brace
on the passenger’s side of the vehicle. SeeEngine
Compartment Overview on page 5-12.1. Turn the pressure cap slowly counterclockwise until
it rst 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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{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. Do not spill coolant on a hot engine.
3. If you have the 3800 V6 engine, remove the
3800 Series II V6 engine cover shield to access
the bleed valve.
3.1. Clean the area around the engine oil ll tube
and cap before removing. Twist the oil ll
tube, with cap attached, counterclockwise
and remove it.
3.2. Lift the engine cover shield at the front, slide
the catch tab out of the engine bracket and
remove the cover shield.
3.3. Put the oil ll tube, with cap attached, in the
valve cover oil ll hole until you’re ready to
replace the cover shield.
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4. After the engine cools, open the coolant air bleed
valve or valves.
3400 V6 engine: There are two bleed valves.
One is located on the thermostat housing.
The other is located on the thermostat bypass tube.3800 V6 engine: There is one bleed valve. It is
located on the thermostat housing. 3400 V6 BLEED VALVE
#1
3400 V6 BLEED VALVE
#23800 Series II V6 Bleed Valve
5-42

5. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the ller neck.
SeeEngine Coolant on page 5-29
If you see a stream of coolant coming from an
air bleed valve, close the valve. Otherwise,
close the valves after the radiator is lled.
6. Rinse or wipe any spilled coolant from the engine
and the compartment.7. If you have the 3800 V6 engine, replace the
3800 Series II V6 engine cover shield.
7.1. Remove the oil ll tube, with cap attached,
from the valve cover.
7.2. Insert the catch tab on the cover shield
under the bracket on the engine.
7.3. Place the hole in the cover shield over the
hole in the valve cover. Install oil ll tube and
cap by twisting clockwise.
8. Then ll the coolant recovery tank to the COLD mark.
9. Put the cap back on the coolant recovery tank,
but leave the radiator pressure cap off.
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10. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
11. By this time, the coolant level inside the radiator
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches
the base of the ller neck.12. Then replace the pressure cap. At any time during
this procedure if coolant begins to ow out of the
ller neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.
13. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the HOT
mark when the engine is hot or at the COLD mark
when the engine is cold.
5-44

Power Steering Fluid
The power steering uid reservoir is located toward the
rear of the engine compartment, on the passenger’s
side of the vehicle.
It will have the above symbol on its cap. SeeEngine
Compartment Overview on page 5-12.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired. SeeEngine Compartment Overview
on page 5-12for reservoir location.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
wipe the cap and the top of the reservoir clean, then
unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then remove
the cap again and look at the uid level on the dipstick.
When the 3400 V6 engine compartment is hot, the level
should be at the H (hot) mark. When it’s cold, the level
should be at the C (cold) mark. If the uid is at the
ADD mark, you should add uid.
For the 3800 V6 engine, the level should be at the
HOT mark when the engine compartment is hot.
If the uid is at the ADD mark, you should add uid.
What to Use
To determine what kind of uid to use, see
Recommended Fluids and Lubricants on page 6-12.
Always use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses and seals.
5-45