2003 CHEVROLET C/K overheating

2-16 Engine Starter Over-Crank Protection
(If Equipped)
Your vehicle may have an engine starter over-crank
protection system. If the starter motor overheats and
shuts off due to over
-cranking, the motor must cool
down before it will reset and allow starter operation.
It can take up to six minutes before the starter will
work again.
Starting Your Gasoline Engine
Engines start differently. The 8th digit of your Vehicle
Identification Number (VIN) shows the code letter for
your engine. See ªVehicle Identification Numberº in
the Index. Follow the proper steps to start the engine.
To start a diesel engine, see ªStarting Your Diesel
Engineº in the Index.
Automatic Transmission
Set the parking brake and move your shift lever to
NEUTRAL (N) or PARK (P) if so equipped. Your
engine won't start in any other position
-- that's a
safety feature.
Manual Transmission
Set the parking brake, shift to neutral and hold the clutch
pedal to the floor while starting the engine.
Starter Motor Operation

The starter motor will disengage if you release
the key or the engine reaches a predetermined
engine speed.

To prevent overheating, the starter motor will
disengage after continuously operating for
15 seconds. You must release the key from the
start position to re
-engage the starter.

The starter motor will not engage if the engine is
already running.

The starter motor will disengage if, after
two seconds, the starter pinion gear does not
engage the flywheel or there is no engine rpm
signal from the engine speed sensor.

2-27
Engine Checks Before Operating
When you've started your engine, let it run for 20 to
30 seconds before you put a load on the engine. But
don't leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped
vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature causes several
conditions which affect engine operation and reduce
engine life.
The engine should be permitted to go through a
warm
-up period. Operate the vehicle at a minimum of
600 rpm during the warm
-up period. During this period
and during operation, the following observations should
be made.
During this warm
-up period, check your warning lights
and gages:

If oil pressure doesn't begin to rise within
15 seconds of starting, stop the engine and
find the cause.
If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating.

If you have air brakes, the dual
-needle air pressure
gage should read at least 115 psi (790 kPa) for both
service systems before you try to move the vehicle.
When air pressure is below 60 psi (420 kPa), the
LOW AIR light will come on and you will hear a
tone alarm. If the pressure doesn't build up or
drops during warm
-up, stop the engine and find
the cause before you try to move the vehicle.
Recommended air pressure before actually driving
away is 120 psi (830 kPa).

The charging system light should come on when
the ignition key is turned to RUN or START and
should go out when the engine is running above idle.
If the light doesn't go out or comes back on during
normal engine operation, have the charging system
checked right away. (This light tells you if the
generator is not charging; it doesn't reflect the
condition of the battery.)

2-84 Trailer Anti-Lock Brake System
Warning Light
If your vehicle is connected
to an anti
-lock brake system
equipped trailer, this light
should come on briefly, as
a check, when you turn on
the ignition.
When this light comes on and stays on, it means there is
something wrong in the trailer anti
-lock brake system.
Have the system repaired immediately.
If an anti
-lock brake system equipped trailer is not
connected, this light is not functional.
Engine Coolant Temperature Gage
United States Canada
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, your engine
coolant might have overheated and your engine may be
too hot. You should pull off the road, stop your vehicle
and turn off the engine as soon as possible.
See ªEngine Overheatingº in the Index. If you have a
Caterpillar

diesel engine, also see your Caterpillar

Operation & Maintenance Manual.

5-
5-1
Section 5 Problems on the Road
Here you'll find what to do about some problems that can occur on the road.
5
-2 Hazard Warning Flashers
5
-3 Other Warning Devices
5
-3 Jump Starting
5
-10 Towing Your Vehicle
5
-17 Engine Overheating5
-20 Cooling System
5
-26 Engine Fan Noise
5
-26 If a Tire Goes Flat
5
-27 Changing a Flat Tire
5
-28 If You're Stuck: In Sand, Mud, Ice or Snow

5-17
6. Turn the stud nut
clockwise several turns
to release the brakes.
Follow the same
procedure to release the
other brake.
7. At the repair facility, apply air pressure of at least
70 psi (480 kPa) to the brake chambers, either from
an external air supply or the vehicle's air system.
8. Turn the stud nut counterclockwise several turns.
Remove the stud from the chamber.
9. Replace the stud and washer and tighten the nut
into the side of the chamber.
10. Replace the rubber cap.Engine Overheating
You will find a coolant temperature warning gage on
your vehicle's instrument panel, as well as a low coolant
warning light. Your vehicle also has a check gages
warning light on the instrument panel.

6-35
Engine Coolant
If your vehicle has a Caterpillar diesel engine, the
Caterpillar Operation & Maintenance Manual provided
with your vehicle has information regarding the proper
coolant to use.
The cooling system 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 ªEngine Overheatingº in
the Index.A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 252F (122C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
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.

6-38
Adding Coolant
If you need more coolant, add the proper DEX
-COOL

coolant mixture at the surge tank, but only when the
engine is cool.
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. Don't spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand
-tight.
Engine Coolant (Caterpillar

Diesel Engine)
If your vehicle has a Caterpillar diesel engine, see the
Caterpillar
Diesel Engine Operation & Maintenance
Manual provided with your vehicle to find out what to
add, also when and how to service your cooling system.
Surge Tank Pressure Cap
The surge tank pressure cap
is located in the engine
compartment, on the
driver's side of the vehicle.
The surge tank pressure cap must be tightly installed.
NOTICE:
Your surge tank pressure cap is a 15 psi (103kPa)
pressure
-type cap for use with medium duty
cooling systems only. It must be tightly installed
to prevent coolant loss and possible engine
damage from overheating.

6-58
Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service, see
your General Motors Warranty booklet for details.
CAUTION:
Poorly maintained and improperly used tires are
dangerous.

Overloading your tires can cause
overheating as a result of too much friction.
You could have an air
-out and a serious
accident. See ªLoading Your Vehicleº in
the Index.
CAUTION: (Continued)
CAUTION: (Continued)

Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.

Overinflated tires are more likely to be
cut, punctured or broken by a sudden
impact
-- such as when you hit a pothole.
Keep tires at the recommended pressure.

Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.