cooling CHEVROLET SUBURBAN 1997 User Guide

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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A CAUTION:
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
-- 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.
I
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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.
2. Then keep turning the pressure cap, but now push
down as you turn
it. Remove the pressure cap.
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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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If the differential is at operating temperature (warm),
add enough lubricant to raise the level
to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant
to raise
the level to
1/2 inch (12 mm) below the filler plug hole.
What to Use
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 system in your vehicle is filled with new
DEX-COOL@ 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 the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F ( 129 * C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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.
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What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOLS coolant which
won’t damage aluminum parts.
If you use this mixture,
you don’t need to add anything else.
J
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. 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:
If’ you use an improper coolant mix, your engine
could overheat and be badly damaged. The repair
cost wouldn’t be covered by your warranty.
Too
much water in the mix can freeze and crack the
engine, radiator, heater core and other parts.
If you have to add coolant more than four times a year,
have
your dealer check your cooling system.
NOTICE:
~~ ~~
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
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I A CAUTION:
Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts and wheel nuts
for replacement.
-
I NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See “Changing a Flat
Tire” in the Index for
more information. Used
Replacement Wheels
I
Putting a used wheel on your vehicle is
dangerous. You can’t know how
it’s been used or
how far it’s been driven. It could fail suddenly
and cause an accident. If you have to replace
a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
If your vehicle has P265/75R16 size tires, don’t
use tire chains. They can damage your vehicle
because there’s not enough clearance.
NOTICE: (Continued)
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Cooling System Capacity (Approximate)
After refill, the level must be rechecked. See “Cooling System” in the Index.
ENGINE VIN QTY Without Rear Heater
“VORTEC” 5700 R 17.5 Quarts (16.5 L)
“VORTEC” 7400 J 25 Quarts (23.5 L)
Crankcase Capacity (Approximate)
After refill, the level must be rechecked. See “Engine Oil” in the Index.
ENGINE VIN QUANTITY WITH FILTER?
“VORTEC” 5700 R 5 Quarts (4.8 L)
“VORTEC” 7400 J 7 Quarts (6.5 L)
?Oil filter should be changed at every oil change.
QTY With Rear Heater
20 Quarts (19 L)
27.5 Quarts (26 L)
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