1997 GMC SAVANA cooling

Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
The coolant level should be at or above the
FULL
COLD mark.
A. Radiator pressure cap
B. Coolant recovery tank
C. Engine fan(s)
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it cools down.
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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.
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 a11 coolant. That could
cause an engine fire, and
you could be burned.
Get any leak fixed before
you drive the vehicle.
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.
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’ 1 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
FULL 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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uu
Steam a--l scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the 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.
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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
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 partially disengages.
You may
also hear this fan noise when you start the engine.
It will go away as the fan clutch partially 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.
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Rear Axle Engine Coolant
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.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in
the Index. The cooling
s stem in your vehicle
is filled with
DEX-COOL
8 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 sysre~ 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 will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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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 water (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@ coolant.
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