engine CHEVROLET COLORADO 2007 1.G Manual Online

How to Check and Add Fluid
The proper uid should be added if the level does
not reach the bottom of the diaphragm when it
is in place in the reservoir. See the instructions
on the reservoir cap.
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 348.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.
345

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 the proper 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.
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 452for more information.
Checking Coolant
The coolant recovery
tank cap has this
symbol on it.
346

It is located toward the rear of the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview
on page 332for more information on location.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be
at FULL COLD, or a little higher. When your
engine is warm, the level could be above the
FULL COLD level.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the coolant
recovery tank.
{CAUTION:
Turning the radiator pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. With the coolant
recovery tank, you will almost never
have to add coolant at the radiator.
CAUTION: (Continued)
CAUTION: (Continued)
Never turn the radiator pressure
cap — even a little — when the engine
and radiator are hot.
Add coolant mixture at the recovery tank, but be
careful not to spill it.
{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.
Occasionally check the coolant level in the
radiator. For information on how to add
coolant to the radiator, seeCooling System
on page 350.
347

Radiator Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is
properly and tightly secured.
SeeEngine Compartment Overview on page 332
for more information on location.
Engine Overheating
A coolant temperature gage is on the instrument
panel. SeeEngine Coolant Temperature Gage
on page 191.
The air conditioning might stop working if the
engine is too hot. This is normal and helps
cool the engine.
If Steam Is Coming From Your Engine
{CAUTION:
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 you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re.
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 re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
348

If No Steam Is Coming From
Your Engine
If you get an engine 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.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades”
underTowing a Trailer on page 306.
If you get the overheat warning with no sign
of steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL and let the engine idle.
2. Turn off the air conditioning.
3. Turn on your heater to full hot at the
highest fan speed and open the windows
as necessary.If you no longer have the overheat warning,
you can drive. Just to be safe, drive slower
for about 10 minutes. If the warning does not
come back on, you can drive normally.
If the warning continues, pull over, stop, and
park your vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. Push down
the accelerator until the engine speed is about
twice as fast as normal idle speed for at least
three minutes while you are parked. If you
still have the warning, turn off the 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.
349

Cooling System
When you decide it is safe to lift the hood,
here is what you will see:
A. Coolant Recovery Tank
B. Engine Cooling Fan
C. Radiator Pressure Cap
If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.When the engine is cold, the coolant level should
be at least up to the FULL COLD mark. 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 else in the cooling system.
350

{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
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 there seems to be no leak, start the engine
again. The engine cooling fan speed should
increase when idle speed is doubled by pushing
the accelerator pedal down. If it does not,
your vehicle needs service. Turn off the engine.
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.
351

How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the coolant
level is not at the FULL COLD mark, add a 50/50
mixture of clean, drinkable water and DEX-COOL
®
engine coolant at the coolant recovery tank. See
Engine Coolant on page 345for more information.
{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.
{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.
When the coolant in the coolant recovery tank
is at the FULL COLD mark, start your vehicle.
352

3. Fill the radiator with the proper DEX-COOL®
coolant mixture, up to the base of the ller
neck. SeeEngine Coolant on page 345
for more information about the proper
coolant mixture.
4. Fill the coolant recovery tank to the
FULL COLD mark.
5. Reinstall the cap on the coolant recovery tank,
but leave the radiator pressure cap off.6. Start the engine and let it run until you can
feel the upper radiator hose getting hot.
Watch out for the engine cooling fan.
7. By this time, the coolant level inside the
radiator ller neck might be lower. If the level
is lower, add more of the proper DEX-COOL
®
coolant mixture through the ller neck until the
level reaches the base of the ller neck.
8. Then replace the pressure cap.
At any time during this procedure if coolant begins
to ow out of the ller neck, reinstall the pressure
cap. Be sure to secure it tightly.
354

Engine Fan Noise
This vehicle has a clutched engine cooling fan.
When the clutch is engaged, the fan spins faster
to provide more air to cool the engine. In most
everyday driving conditions, the clutch is not
engaged. This improves fuel economy and reduces
fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the
fan speed increases when the clutch engages.
So you may hear an increase in fan noise.
This is normal and should not be mistaken as
the transmission slipping or making extra shifts.
It is merely the cooling system functioning
properly. The fan will slow down when additional
cooling is not required and the clutch disengages.
You may also hear this fan noise when you
start the engine. It will go away as the fan
clutch disengages.
Power Steering Fluid
The power steering uid
reservoir is located near
the front of the engine
compartment, behind
the radiator. SeeEngine
Compartment Overview
on page 332for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering uid unless you suspect there is a leak
in the system or you hear an unusual noise.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
355