1997 CHEVROLET SUBURBAN 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:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
0 Tow a trailer. See “Driving on Grades” in the Index.
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.
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
-- AUTOMATIC OVERDRIVE (a)
for automatic transmissions. 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 oflthe
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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Cooling System -- Gasoline Engines
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(s)
LA
CAUTION:
I
If your vehicle has air conditioning, the auxiliary
electric 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.
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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.
The coolant level should be at or above the COLD mark. I NOTICE:
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.
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.
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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 or above the COLD
mark, add a 50/50 mixture of
clean water (preferably distilled) and DEX-COOL@
(silicate-free) antifreeze at the coolant recovery tank. (See
“Engine Coolant” in the Index for more information.)
-
A CAUTION:
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.
CAUTION: (Continued) CAUTION:
(Conwed)
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.
I 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.
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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 or
above 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
mix
directly to the radiator, but be sure the cooling system is
cool before you do it.
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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 fan(
s).
7. 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 Rvl coolant mixture
through the filler neck until the level reaches the
base
of the filler neck.
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 If a Tire Goes Flat
Your 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 fan is spinning slower and 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 as the clutch more fully 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. 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.
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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.
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. If you have a four-wheel-drive vehicle,
be sure the transfer case is in a drive
gear
-- not in NEUTRAL (N).
4. firn off the engine.
To be even more certain the vehicle won't move,
you can put 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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