2003 CHEVROLET ASTRO CARGO VAN engine

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. Engine Cooling 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 the ADD mark.
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. 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 ®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, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
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-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50 000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
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 ADD mark, add a 50/50 mixture ofclean
drinkable water, and DEX-COOLžengine coolant at the
coolant recovery tank. SeeEngine Coolant on
page 5-28for more information.
{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 wouldn't 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
žcoolant.
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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.
{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.
When the coolant in the coolant recovery tank is at the
ADD mark, start your vehicle.
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3. Fill the radiator with the proper DEX-COOLž
coolant mixture, up to the base of the ®ller
neck. SeeEngine Coolant on page 5-28for more
information about the proper coolant mixture.4. Then ®ll the coolant recovery tank to the ADD mark.
5. Put the cap back on the coolant recovery tank,
but leave the pressure cap off.
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6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. 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
žcoolant mixture
through the ®ller neck until the level reaches
the base of the ®ller neck.
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.
Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
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Power Steering Fluid
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. See
Engine Compartment Overview
on page 5-14for 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.
The level should be at the FULL COLD mark.
If necessary, add only enough ¯uid to bring the
level up to the mark.
What to Use
To determine what kind of ¯uid to use, seePart D:
Recommended Fluids and Lubricants on page 6-32.
Always use the proper ¯uid. Failure to use the proper
¯uid can cause leaks and damage hoses and seals.
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Windshield Washer Fluid
What to Use
When you need windshield washer ¯uid, be sure to read
the manufacturer's instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a ¯uid that has
sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it. Add
washer ¯uid until the
tank is full.
Notice:
·When using concentrated washer ¯uid, follow
the manufacturer's instructions for adding
water.
·Don't mix water with ready-to-use washer ¯uid.
Water can cause the solution to freeze and
damage your washer ¯uid tank and other parts
of the washer system. Also, water doesn't
clean as well as washer ¯uid.
·Fill your washer ¯uid tank only three-quarters
full when it's very cold. This allows for
expansion if freezing occurs, which could
damage the tank if it is completely full.
·Don't use engine coolant (antifreeze) in your
windshield washer. It can damage your
washer system and paint.
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Brakes
Brake Fluid
Your brake master cylinder reservoir is ®lled with DOT-3
brake ¯uid. SeeEngine Compartment Overview on
page 5-14for the location of the reservoir.There are only two reasons why the brake ¯uid level in
the reservoir might go down. The ®rst is that the
brake ¯uid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
the ¯uid level goes back up. The other reason is
that ¯uid is leaking out of the brake system. If it is, you
should have your brake system ®xed, since a leak
means that sooner or later your brakes won't work well,
or won't work at all.
So, it isn't a good idea to ªtop offº your brake ¯uid.
Adding brake ¯uid won't correct a leak. If you add ¯uid
when your linings are worn, then you'll have too
much ¯uid when you get new brake linings. You should
add (or remove) brake ¯uid, as necessary, only when
work is done on the brake hydraulic system.
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