1996 CHEVROLET EXPRESS engine overheat

Downloaded from www.Manualslib.com manuals search engine Engine Overheating (Gasoline Engine)
You will find a coolant temperature gage on your
vehicle instrument panel.
If you have a diesel engine,
you will also find a low coolant light
on your
instrument panel.
If your vehicle has a diesel engine, see "Engine
Overheating"
in the GM Diesel Engine Supplement.
If Steam Is Coming From Your Engine
--- - >?.
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay
away
from the engine if you see or hear steam coming
from it. Just turn it
off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before
opening the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered
by your warranty.
5-10

Downloaded from www.Manualslib.com manuals search engine 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:
0 Climb a long hill on a hot day.
0 Stop after high-speed driving.
0 Idle for long periods in traffic.
0 Tow a trailer. See “Driving on Grades” in the Index.
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 window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift
to the highest gear while
driving
-- DRIVE (D).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 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, you can idle the engine
for two or three minutes while you’re parked,
to 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 ofthe engine and get everyone out qf the
vehicle
until it cools down.
You may decide not to lift the hood but to get service
help right away.
5-11

Downloaded from www.Manualslib.com manuals search engine 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.
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.
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 5060 mixture of
clean water (preferably distilled) and DEX-COOL’”
(orange-colored, silicate-free) antifreeze at the coolant
recovery tank. (See “Engine Coolant”
in the Index for
more information.)
Adding only plain water to your cooling sy,,,m
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
TM antifreeze.
c 11

Downloaded from www.Manualslib.com manuals search engine 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.
A CAIJTION:
-
You can be b ed 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.
5-14

Downloaded from www.Manualslib.com manuals search engine 5. Put the flat end of the extension on an angle through
the
hole in the rear door frame, above the bumper.
Turn the ratchet clockwise until the tire is against the
underside
of the vehicle.
You will hear two “clicks”
when the tire is up all the
way. Try
to move the tire with your hands to make
sure
it is securely in place.
Return the jacking equipment to the proper location.
Secure the items and replace the jack cover.
If You’re Stuck: In Sand, Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking’’ can help you get out when you’re stuck, but
you must use caution.
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts
of the
vehicle can overheat. That
could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels
as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
L 2t

Downloaded from www.Manualslib.com manuals search engine Engine Coolant
The cooling system in your vehicle is filled with new
DEX-COOL
TM (orange-colored, silicate-free) engine
coolant. This coolant is designed to remain
in your
vehicle for 5 years or 100,000 miles ( 166 000 km),
whichever occurs first.
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 5060 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
NOTICE:
When adding coolant it is important that you use
DEX-COOL TM (orange-colored, silicate-free)
coolant meeting
GM Specification 6277M.
If silicated coolant 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.
6-20

Downloaded from www.Manualslib.com manuals search engine What to Use
Use a mixture of one-half
clean water (preferably
distilled) and one-half DEX-COOL
Rul (orange-colored,
silicate-free) antifreeze that meets
GM Specification
6277M, which won’t damage aluminum parts. Use
GM Engine Coolant Supplement (sealer) (GM Part
No. 3634621) with any complete coolant change. If you
use this mixture, you don’t need
to add anything else.
’/d 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 TM (orange-colored,
silicate-free) antifreeze.
6-21

Downloaded from www.Manualslib.com manuals search engine 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.
Checking Coolant
When your engine is cold, the coolant level should be at
FULL COLD, or a little higher.
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