2007 CHEVROLET COBALT radiator

Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. This system does not have its own
reservoir. It receives uid from the brake master
cylinder reservoir.
SeeBrakes on page 318for more information.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, 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, seeEngine
Overheating on page 309.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down
to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
302

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as 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 would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not 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 extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 406for more information.
303

Checking Coolant
The coolant surge tank is located in the engine
compartment on the driver’s side of the vehicle.
SeeEngine Compartment Overview on page 290
for 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 — even a little — 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 COLD FILL line.
304

A. Electric Engine Cooling Fans
B. Intercooler System Pressure Cap
C. Coolant Surge Tank and Pressure Cap
{CAUTION:
An electric engine cooling 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.
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
The coolant level should be at the COLD FILL line.
If it is not, you may have a leak at the pressure cap
or in the radiator hoses, heater hoses, radiator,
water pump, or somewhere in the cooling system.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
CAUTION: (Continued)
2.0L L4 Supercharged Engine
312

CAUTION: (Continued)
Do not 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 your vehicle is equipped with the 2.2L or
2.4L L4 engine and there seems to be no leak,
with the engine on, check to see if the electric
engine cooling fan is running. If the engine is
overheating, the fan should be running. If it is not,
your vehicle needs service.
If your vehicle is equipped with the
2.0L L4 Supercharged engine and 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, the fans should be
running. If they are not, your vehicle needs service.
Notice:Engine damage from running your
engine without coolant is not covered by
your warranty.Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner,
at 30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
How to Add Coolant to the Coolant
Surge Tank
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure
could cause your engine to overheat and
be severely damaged.
If you have not found a problem yet, check to
see if coolant is visible in the coolant surge tank.
If coolant is visible but the coolant level is not at the
COLD FILL line, add a 50/50 mixture of clean,
drinkable water 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. SeeEngine Coolant on
page 302for more information.
313

2.2L and 2.4L L4 Engines
If no coolant is visible in the coolant 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 — 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.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as 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 would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
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 mixture.
314

{CAUTION:
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. Do not
spill coolant on a hot 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 counterclockwise
about two or two and one-half turns. If you
hear a hiss, wait for that to stop. This will allow
any pressure still left to be vented out the
discharge hose.2. Then keep
turning the
pressure cap
slowly, and
remove it.
315

3. Fill the coolant surge tank with the proper
mixture, to the COLD FILL line on the tank.
Wait about ve minutes, then check to
see if the level is below the COLD FILL line.
If the level is below the line, add additional
coolant to bring the level up to the line.
Repeat this procedure until the level remains
constant at the COLD FILL line for at least
ve minutes.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.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower
than the COLD FILL line, add more of the
proper mixture to the coolant surge tank
until the level reaches the COLD FILL line.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
See your dealer, if necessary.2.0L L4 Supercharged Engine
If no coolant is visible in the coolant surge tank,
you will need to either see your dealer or refer
to the Dealer Service Manual for a special coolant
service ll procedure to ensure enough coolant
is added. To purchase a service manual, see
Service Publications Ordering Information
on page 430.
316