radiator CHEVROLET SUBURBAN 1993 Owners Manual

Cooling System
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When you decide it's safe to lift the hood, here's what you'l\
l see:
A. Coolant recovery tank
B. Radiator pressure cap
C. Engine fan
A
An 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.
CAUTION
If the coolant inside the coolant recovery tank or surge tank is \
boiling, don't
do anything else until it cools down.
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The coolant level should be at or above COLD. 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.
CAUTION
A
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, 1‘ it coulc
lose all coolant. That could cause an engine fire, and you could
be
I burned. Get any leak fixed before you drive the vehicle.
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If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running. If the engine is overheating, the fan \
should be running.
If
it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
If
it doesn’t, your vehicle needs service. Turn off the 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 or above
COLD, add a 50150 mixture of clean water (preferably distilled) and a proper
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antifreeze at the coolant recovery tank. (See “Coolant” i\
n the Index for more information about the proper coolant mix.)
Adding only plain water to your cooling system can be dangerou\
s. 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 50150 mix of clean water and a proper antifreeze. I I
NOTICE I
In cold weather, water can freeze and crack the engine. radiator, heater
I core and other parts. Use the recommended coolant.
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CAUTION
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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
is at or above COLD, start your
vehicle.
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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
radiator is cool before you
do it.
I CAUTION
4 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 capeven a little-they can come out at high
speed. Never turn the cap when the cooling system, Including the
radiator pressure cap, is hat. Wait for the cooling system and radiato
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 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.
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PO244
2. Then keep turning the pressure cap, but now push down as you turn it.
Remove the pressure cap.
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3. Fill the radiator with the proper mix, up to the base of the filler neck.
4. Then fill the coolant recovery tank to COLD.
5. Put the cap back on the coolant recovery tank, but leave the radi\
ator
pressure
cap off.
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K2550
6. Start the engine and let it run until you can feel the upper radiator hose
getting hot. Watch out for the engine fan@).
7. By this time, the coolant level inside the radiator filler neck m\
ay 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.
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8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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Service & Appearance Care
The following explains your cooling system and how to add cool\
ant when it is
low.
If you have a problem with engine overheating, see “Engine
Overheating” in the Index.
The proper coolant for your vehicle
will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use:
Use a mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification
6038-M,” which won’t damage aluminum parts. Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change.
If
you use these, you don’t need to add anything else.
Adding only plain water to your cooling system can be dangerous.
I
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. Us\
e
a 50/50 mix of clean water and a proper antifreeze.
jIi ,yo.w use an improper coolant mix, your engine .coutd overheat andi
badly damaged. The repair cost wouldn’t be covered by your warranty.’ TP~
much water in ;the mix can freeze and crack the engine, radiator, .heater
wre-ad -.other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when th\
e engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to
add
coolant.
.. .. ..
If you have to add coolant mdre than four times a year, have your dealer
check
your cooling system.
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k
NOTICE
f YOU use the proper coolant, you don’t have to add extra inhibitors or
idditives which claim to improve the system. These can be harmful
Adding Coolant
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To Check Coolant: When your engine is cold, the coolant level should be at
COLD, or a little higher. When your engine is warm, the level shoul\
d be up
to HOT, or a little higher.
To Add Coolant: If you need more coolant, add the proper mix at the
coolant recovery tank.
I CAUTION
4
Turning the radiator pressure cap when the engine and radiator are
hot can allow steam and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will almost never have to
add coolant at the radiator. Never turn the radiator pressure
I cap-even a little-when the engine and radiator are hot. I
Add coolant mix at the recovery tank, but be careful not to spill it.
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1 CAUTION I
You can be burned if you spill coolant on hot engine parts. Coolant
- b contains ethylene glycol, and it will burn if the engine parts are hot
I enough. Don’t spill coolant on a hot engine. I
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Service & Appearance Care
Radiator Pressure Cap
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1 NOTICE
four radiator pressure cap is a 15 psi (105 kPa) pressure-type cap and
nust be tightly installed to prevent coolant loss and possible engine
mage from overheating. Be sure the arrows on the cap line up \
with
werffow tube
on the radiator filler neck.
-m recommended.
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Thermostat
Engine coolant temperature is controlled by a thermostat in the engine coolant
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.
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Composite Headlights
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1. Remove the two screws at the top of the radiator support.
2. Pull the composite headlight lens out.
3. Unplug the electrical connector.
4. Turn the bulb counterclockwise and remove it.
5. Put the new bulb in and turn it clockwise until it is tight.
6. Plug in the electrical connector.
7. Put the headlight back into the vehicle and tighten the two screws.
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