2003 CHEVROLET CORVETTE radiator cap

Checking Coolant
The coolant surge tank is located in the engine
compartment behind the passenger's side headlamp.
See
Engine Compartment Overview on page 5-12for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap Ð even a little Ð when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark. The FULL COLD mark is on the front
of the coolant surge tank. Don't over®ll the surge tank.
Too much coolant can result in an over¯ow when
the ¯uid is hot.
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The coolant level should be at or above the FULL
COLD mark. If it isn't, you may have a leak at the
pressure cap or in the radiator hoses, heater hoses,
radiator, water pump or somewhere else in the cooling
system.
{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 ®re, and you could be
burned. Get any leak ®xed before you drive the
vehicle.
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, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant isn't covered by your warranty.
See ªOverheated Engine Protection Operating
Modeº in the Index for information on driving to a
safe place in an emergency.
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Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50 000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
How to Add Coolant to the Coolant
Surge Tank
If you haven't found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level isn't at the FULL COLD mark on the
coolant surge tank, add a 50/50 mixture of
clean,
drinkable waterand DEX-COOLžcoolant 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 on page 5-23for more
information.If no coolant is visible in the surge tank, add coolant as
follows:
{CAUTION:
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 Ð even a little Ð 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.
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1. Park the vehicle on a level surface. 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
counterclockwise about one-quarter turn 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 ®ll the coolant surge tank with the proper
mixture, to the FULL COLD mark on the coolant
surge tank.
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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 fan(s).
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 on
the coolant surge tank.5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
5-34

Fuel System Inspection
Inspect the complete fuel system for damage or leaks.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect all pipes,
®ttings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
Rear Axle Service
Check the gear lubricant level in the rear axle and add if
needed. SeeRear Axle on page 5-46. A ¯uid loss
may indicate a problem. Check the axle and repair it if
needed.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
cha®ng, etc. Inspect disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. You may need to
have your brakes inspected more often if your driving
habits or conditions result in frequent braking.
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