1997 CHEVROLET ASTRO cooling

Downloaded from www.Manualslib.com manuals search 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 Fan
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else
until it cools down.
The coolant level should be at the ADD mark.
If it isn’t, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere
else in
the cooling system.
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Downloaded from www.Manualslib.com manuals search engine A 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 fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
I NOTICE:
Engine damage from running your engine
without coolant isn’t covered by your warranty.
If there seems to be no leak, start the engine again. See
if the fan speed increases when idle speed is doubled by
pushing the accelerator pedal down.
If it doesn’t, your
vehicle needs service. Turn off the engine.
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 of clean water
(prefembly distilled) and DEX-COOL@ (silicate-free)
antifreeze at the coolant recovery tank. (See “Engine
Coolant”
in the Index for more information.)
,/!
CAU [ON:
---
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will. Your vehicle’s coolant warning
system
is set for the proper coolant mix. With
plain water or the wrong mix, 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 mix of clean
water and DEX-COOL@ coolant.
5-16

Downloaded from www.Manualslib.com manuals search engine 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 mix. 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.
If the overheat warning continues, there’s one more
thing
you can try. You can add the proper coolant mix
directly
to the radiator, but be sure the cooling system is
cool before
you do it.
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Downloaded from www.Manualslib.com manuals search engine JTION:
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
-0 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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Downloaded from www.Manualslib.com manuals search engine 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.
I
2. Then keep turning the
pressure cap, but now
5-19

Downloaded from www.Manualslib.com manuals search engine 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.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially if
you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to leak out slowly.
But if you should ever have a “blowout,” here are a few
tips about what to expect and what
to do:
If a front tire fails, the
flat tire will create a drag that
pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer
to maintain lane position, and then gently brake to
a stop well
out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid.
In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering
the way you want the vehicle to go. It may be
very bumpy and noisy, but
you can still steer. Gently
brake to a stop
-- well off the road if possible.
If a tire goes flat,
the next part shows how to use your
jacking equipment to change a flat tire safely.
5-22

Downloaded from www.Manualslib.com manuals search engine Rear Axle What to Use .
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant and when to change it. See
“Scheduled Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need
to add some lubricant. Add enough lubricant
to raise
the level to the bottom of the filler plug hole. Refer to the Maintenance Schedule to
determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants”
in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with new
DEX-COOL
J engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km) whichever occurs first, if you add only
DEX-COOL’ extended life coolant.
The following explains your cooling system and how to
add coolant when
it is low. If you have a problem with
engine overheating, see “Engine Overheating”
in
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant for
your vehicle
will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning lights and gages work as they should.
6-25

Downloaded from www.Manualslib.com manuals search engine I
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 wuter (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum parts.
If you use this mixture,
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will, Your vehicle’s coolant warning
system is set for the proper coolant mix. With
plain water or the wrong mix, 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 mix of clean
water and DEX-COOL@ antifreeze.
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