cooling CHEVROLET SUBURBAN 1994 Owners Manual

The air flow can be blended between the two positions. To blend between
positions press the side
of the button showing the area where you would like
more air flow. The system will automatically begin to blend toward the
position chosen.
To stop the system between positions, just press the SAME
side of the button again.
Right Button
Defrost (Top) : This setting operates the defroster. Air comes out near the
bottom of the windshield and at your front side windows. Use this setting,
along with a heat setting, when you get fog or ice on the windshield.
Heater (Bottom) : Press the bottom of this button and air comes out near
the floor. This setting, along
with a heat setting, is best for passenger
comfort in cold weather.
The air flow can be blended between the two positions.
To blend between
positions press the side of the button showing the area where
you would like
more air
flow. The system will automatically begin to blend toward the
position chosen. To stop the system between positions, just press
the SAME
side of the button again.
A/C Button
Press the button marked A/C to turn your air conditioner on and off. The
A/C symbol will light on your display and air will come out of your
instrument panel vents. The fan will automatically be set on
LOW .
When you press the A/C button to turn the air conditioner off, the system
will operate in the vent mode. When you turn the air conditioner back
on,
the system will operate in the mode that you last selected unless the OFF
button was pressed.
MAX Button
If you press the MAX button, the air in your vehicle will be recirculated.
With the air conditioner on,
MAX will give you maximum cooling. It can
also be used
in all modes to help keep dust out of your vehicle. When MAX
is selected, REC will light on your display.
If your air conditioner develops high system pressure, it will automatically
go into the
MAX mode and REC will light on your display. The A/C
system will remain in the MAX mode, even if you press the MAX button,
until system pressure returns to a normal level.
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After Off-Road Driving
Remove any brush or debris that has collected on the underbody, chassis or
under the hood. These accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings cleaned and checked.
These substances can
cause glazing and uneven braking. Check the body
structure, steering, suspension, wheels, tires, and exhaust system for
damage. Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due to off-road use. Refer
to the Maintenance Schedule for additional information.
Driving at Night
Night driving is more dangerous than day driving. One reason is that some
drivers are likely
to be impaired - by alcohol or drugs, with night vision
problems, or by fatigue.
Here are some tips
on night driving.
0 Drive defensively.
0 Don't drink and drive.
0 Adjust your inside rearview mirror to reduce the glare from headlights
behind
you.
Since you can't see as well, you may need to slow down and keep more
space between you and other vehicles.
up
only so much road ahead.
Slow down, especially on higher speed roads. Your headlights can light
0 In remote areas, watch for animals.
If you're tired, pull off the road in a safe place and rest.
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Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can work
hard on mountain roads.
Know how to go down hills. The most important thing to know is this:
let your engine do some
of the slowing down. Shift to a lower gear
when you go down
a steep or long hill.
0 Know how to go uphill. You may want to shift down to a lower gear.
The lower gears help cool your engine and transmission, and you can
climb the hill better.
0 Stay in your own lane when driving on two-lane roads in hills or
mountains. Don’t swing wide or cut across the center of the road. Drive
at speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There could be something in
your lane, like
a stalled car or an accident.
You may see highway signs on mountains that warn of special
problems. Examples are long grades, passing or no-passing zones, a
falling rocks area, or winding roads. Be alert to these and take
appropriate action.
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Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important in trailer operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, and brake
adjustment. Each
of these is covered in this manual, and the Index will help
you find them quickly. If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see
that all hitch nuts and bolts are tight.
Trailer Light Wiring
See “Trailer Wiring Harness” in the Index.
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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.
Tow a trailer.
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
3. If you’re in a traffic jam, shift to “N’ (Neutral).
window
as necessary.
If you
no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten 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 OFF THE 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.
Cooling System -Gas Engines
When you decide it’s
safe to lift the hood,
here’s what you’ll see:
A. Coolant recovery
“I tank
B. Engine fan(s)
C. Radiator pressure
cap
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If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until it cools down.
P
The coolant level
should be at or above
the
COLD 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.
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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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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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 to the left
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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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).
By this time the coolant level inside the radiator 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.
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 pressure cap
line up
like this.
Cooling System -Diesel Engines
When you decide it's
safe
to lift the hood,
here's what
you'll see:
A
A. Coolant surge
tank pressure cap
B. Engine fan(s)
C. Radiator
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If the coolant inside the coolant surge tank is boiling, don't do anything else
until it cools down.
The coolant level
should be at
or above
the
COLD 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.
NOTICE:
Engine damage from running your engine without coolant isn't
covered by your warranty.
If there seems to be no leak, start the engifie 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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