1995 CHEVROLET SUBURBAN engine

Towing From the Rear
Engine Overheating
If Steam Is Coming From Your Engine
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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.
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.
0 Idle for long periods in traffic.
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:
I. 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
- AUTOMATIC OVERDRIVE (a) or
DRIVE (3) for automatic transmissions.
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.
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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 ofthe 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 - Gasoline Engines
When you decide it’s safe to lift the hood, here’s what you’ll see:
A. Coolant recovery tank
B . Engine fan( s)
C. Radiator pressure cap
If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until
it cools down.
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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.
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
the
COLD mark, add a 50/50 mixture of clean water (preferably distilled)
and a proper antifreeze at the coolant recovery tank. (See “Engine Coolant”
in the Index for more information about the proper coolant mix.)
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NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or.
heater core and other parts. Use the recommended coolant.
E
When the coolant in the coolant recovery tank is at or above the COLD
mark, start your vehicle.
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I
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).
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 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 the pressure cap line up like this.
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Cooling System - Diesel Engines
When you decide it’s safe to lift the hood, here’s what you’ll see:
A. Coolant surge tank pressure cap
B. Engine fan(s)
C. Radiator
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
1 or somewhere else in
the cooling system.
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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 Surge Tank
NOTICE:
The diesel engine has a specific coolant fill procedure. Failur\
e to
follow this procedure could cause your engine to overheat and \
be
severely damaged.
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark, add a 50/50 mixture of clean water (preferably distilled) and a proper
antifreeze at the coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap, is cool before you do it. (See
“Engine Coolant” in the Index for more information about the proper
coolant mix.)
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