cooling CHEVROLET EXPRESS 1998 1.G User Guide

Downloaded from www.Manualslib.com manuals search engine 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. 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.
NOTICE:
I
Engine damage from running your engine
without coolant isn’t covered by your warranty.
I I
If there seems to be no leak, start the engine again.
See if the engine cooling 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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Downloaded from www.Manualslib.com manuals search 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 FULL COLD mark, add a 50/50 mixture of
clean water (preferably distilled) and DEX-COOL@
engine coolant 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 mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
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 mixture 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 mixture.
I
.. .
5-16

Downloaded from www.Manualslib.com manuals search engine I CAUTION: I
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
mixture directly
to the radiator, but be sure the cooling
system is cool before you do it,
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
CAUTION: (Continued pressure cap
-- even
a lit 0- ey 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.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
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Downloaded from www.Manualslib.com manuals search engine I .....
6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out
for the
engine cooling fan.
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@ 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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Downloaded from www.Manualslib.com manuals search engine 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 partially disengages.
You may also hear this fan noise when you start
the engine. It will go away as the fan clutch
partially 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.

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
DEX-COOL engine coolant. This coolant is designed
to remain in your vehicle for
5 years or 150,000 miles
(240
000 kmg whichever occurs first, if you add only
DEX-COOL extended life coolant.
8
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 will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F (1 29” C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning lights and gages work as
they should.

Downloaded from www.Manualslib.com manuals search engine 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.
I
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 mixture will. Your vehicle’s coolant
warning system is set for the
proper coolant
mixture. With plain water or the wrong mixture,
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 mixture of clean water and
DEX-COOL@ coolant.
6-22

Downloaded from www.Manualslib.com manuals search engine NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty. Too much water in the mixture 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:
Checking Coolant
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. When
your engine is cold, the coolant level shoi FULL COLD, or a little higher. Ad
be
at

Downloaded from www.Manualslib.com manuals search engine Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine cooling system. The thermostat stops the
flow
of coolant through the radiator until the coolant
reaches
a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
Power :ring !
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is a leak in the system or
you hear an unusual noise. A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap
and the top of the reservoir clean, then unscrew the
cap and wipe the dipstick with
a clean rag. Replace
the cap and completely tighten it.
Then remove the
cap again and look at the fluid level on the dipstick.
The level should be at the
FULL COLD mark. If
necessary, add only enough fluid to bring the level up
to the mark.
To prevent contamination of brake fluid, never check or
fill the power steering reservoir with the brake master
cylinder cover
off.
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