1998 CHEVROLET CORVETTE cooling

Downloaded from www.Manualslib.com manuals search engine The coolant level should be at or above the FULL
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.
A CAUTION:
I
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 if you keep running your engine
without coolant isn’t covered by your warranty.
See “Overheated Engine Protection Operating
Mode” in the Index.
If there seems to be no leak, with the engine on, check to
see if the electric engine cooling
fans are running. If the
engine is overheating, both
fans should be running. If
they aren’t.
vow vehicle needs service.
5-17

Downloaded from www.Manualslib.com manuals search engine How to Add Coolant to the Coolant
Surge 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@
coolant 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.)
A CAUTION:
I
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 coolant surge
tank pressure cap -- even a little -- they can come
out at
high speed. Never turn the cap when the
cooling system, including the coolant surge
tank
pressure cap, is hot. Wait for the cooling system
and coolant surge
tank pressure cap to cool if you
ever have to
turn the pressure cap.

Downloaded from www.Manualslib.com manuals search engine 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.
NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
So
use the recommended coolant.
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.
5-19

Downloaded from www.Manualslib.com manuals search engine 1. You can remove the coolant surge tank pressure cap
when the cooling system, including the coolant surge
tank pressure cap and upper radiator hose, is no
longer hot. Turn the pressure cap slowly about
one-quarter turn to the left and then stop.
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 slowly, and
remove it.
3. Then fill the coolant surge tank with the proper
mixture, up to the
FULL COLD mark.

Downloaded from www.Manualslib.com manuals search engine 4. With the coolant surge tank pressure cap off, start the
engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the
FULL COLD mark.
5. Then replace the pressure cap. Be sure the pressure
cap is tight.
5-21

Downloaded from www.Manualslib.com manuals search engine 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.
What to Use
To add lubricant when the level is low, use Axle
Lubricant (GM Part
No. 12345977) or SAE 8OW-90
GL-5 gear lubricant. To completely refill after draining,
add
4 ounces (1 18 ml) of Limited-Slip Differential
Lubricant Additive (GM Part
No. 1052358). Then fill to the bottom
of the filler plug hole with Axle Lubricant
(GM Part No. 12345977) or SAE 8OW-90 GL-5
gear lubricant.
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 km) whichever occurs first, if you add only
DEX-COOL’ extended life coolant.
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).
8
0 Give boiling protection up to 265 “F (129” C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gauges work as
they should.
6-22

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
/II CALTTION:
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.
6-23

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:
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
The coolant surge tank is in the engine compartment
behind the headlamp.