1996 CHEVROLET ASTRO engine

If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get
a little too hot when you:
0 Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” in
If you get the overheat warning with no sign of steam,
try this for a minute or
so:
1. If you have an air conditioner, turn it off.
the Index.
2. Turn on your heater to full hot at the highest fan
speed and open
the window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D).
If you no longer have the overheat warning, you
can drive. Just
to be safe, drive slower for about
10 minutes. If the warning doesn’t come back on,
you
can drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back
to normal idle speed
after two or three minutes. Now see if the warning stops.
But then,
if you still have the warning, turn ofthe
engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
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When you decide it’s safe to lift the hood, here’s what
you’ll see: If the coolant inside the coolant recovery tank is boiling,
don’t do anything else
until it cools down.
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan 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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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.
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 (preferably distilled) and DEX-COOL TM
(orange-colored, silicate-free) antifreeze at the coolant
recovery tank. (See “Engine Coolant’’
in the Index for
more information.)
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 TM antifreeze.
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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 mix.
I A 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.
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.

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine fan.
filler neck may be lower.
If the level is lower, add
more of the proper
mix through the filler neck until
the level reaches the base of the filler neck.
7. By this time the coolant level inside the radiator
8. 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. Be sure the
arrows on the pressure cap line up like this.
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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 every day 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 4‘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.
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Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning flashers.
'!!!h CAUTION:
I
Changing a tire can cause an injury. The vehicle
can slip off the jack and roll over you or other
people. You and they could be badly injured.
Find
a level place to change your tire. To help
prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in PARK (P).
3. 'hrn off the engine.
4. Put the wheel blocks at the front and
rear of the tire farthest away from the
one being changed. That would be the
tire on the other side of the vehicle, at
the opposite end. The
following steps will tell
you how to use the jack and
change a tire.
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If You’re Stuck: In Sand, Mud, Ice
or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help
you get out when you’re stuck, but
you must use caution.
A CAUTION:’
I
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts of the
vehicle can overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels
as little as possible. Don’t
~ spin the wheels above 35 mph (55 km/h) as shown
~ on the speedometer.
I
NOTICE:
Spinning your wheels can destroy parts of your
vehicle
as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
For information about using tire chains
on your vehicle,
see “Tire Chains” in
the Index.
Rocking your vehicle to get it out:
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE
(R) and a forward gear,
spinning the wheels as little as possible. Release the
accelerator pedal while you shift, and press lightly
on
the accelerator pedal when the transmission is in gear. If
that doesn’t get
you out after a few tries, you may need
to be towed out. If you do need to be towed out, see
“Towing Your Vehicle’’’ in the Index.
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