engine overheat GMC ENVOY 1998 User Guide

1 h 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 fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
NOTICE: I
Engine damage from running your engine
without coolant isn’t covered by your
1 warranty.
If there seems to be no leak, start the engine again. See
if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off
the engine.
How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t
at the ADD mark, add a 50/50 mixture of clean
brater (preferably distilled) and DEX-COOL@ engine
coolant at the coolant recovery tank. (See “Engine
Coolant”
in the Index for more information.)
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.
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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.
A 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 the coolant in the coolant recovery tank is at the
ADD r&ark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling system is cool before you do
it.
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If You’re Stuck: In Sand, Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help
you get out when you’re stuck, but
you must use caution.
A CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts
of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
I
NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth, you can destroy your transmission.
For information about using tire chains on your vehicle,
see “Tire Chains”
in the Index.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change
it. See
”Scheduled Maintenance Services”
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant. When
the differential is cold, add enough lubricant to
raise the level to
1/2 inch (12 mm) below the filler
plug hole.
When the differential
is at operating temperature
(warm), add enough lubricant to raise the level
to the
bottom
of the filler plug hole.
What to use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See “Recommended Fluids and
Lubricants“
in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL J 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.
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A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 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
0- 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.
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.
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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
When your engine is cold, the coolant level should be at
ADD, or a little higher. When your engine is warm, the
level should be up to
FULL HOT, or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the cwolarzt recovery tank.
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-
A 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. 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.
A CAUTION:
I
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.
Radiator Pressure Cap
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant
loss and possible engine damage
from overheating. Be sure the arrows on the cap
line
up with the overflow tube on the radiator
filler neck.
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Engine (Continued) .............................. 6-9
Exhaust
..................................... 2-24
FanNoise
................................... 5-20
Identification
................................ 6-54
OilLevelCheck
.............................. 7-39
Overheating
................................. 5-11
Specifications
................................ 6-60
Engine Compartment Fuse Block
.................. 6-58
Engineoil
.................................... 6-10
Adding
..................................... 6-11
Additives
................................... 6-13
Checking
................................... 6-11
Kindtouse
................................. 6-12
Pressure Gage
................................ 2-69
Used
....................................... 6-14
When to Change
.............................. 6- I3
Exhaust, Engine
................................ 2-24
Exit Lighting
.................................. 2-39
Express-Down Window
.......................... 2-29
Fabric Cleaning
............................... 6-46
Filling
a Portable Fuel Container .................... 6-7
FillingYourTank
................................ 6-5
Fi 1 ter
Air
........................................ 6-14
Remote Oil .................................. 6- 14
Finish Care .................................... 6-5 1
Finish Damage ................................. 6-52
Running While
Parked
......................... 2-25
Starting
..................................... 2-15
Engine Coolant
................................. 6-2 1
FirstGear ..................................... 2-20
Flashers. Hazard Warning
......................... 5-2
Flat Tire. Changing
............................. 5-21
Fluids and Lubricants
............................ 7-4.5
FogLampSwitch ............................... 2-38
Foreign Countries. Fuel ........................... 6-5
Four-wheel Drive
......................... 2-26. 6-20
French Language Manual 11
FrontAxle .................................... 6-21
Front Reading Lamps
....................... 2.39. 2.43
Front Storage Area .............................. 2-45
FrontTowing
................................... 5-9
Filling a Portable Container
...................... 6-7
Filling Your Tank
.............................. 6-5
Foreign Countries .............................. 6-5
Engine Compartment
.......................... 6-58
Instrument Panel
............................. 6-56
Fuses and Circuit Breakers
....................... 6-55
Gages
.. ...........................
Front Turn Signal Lamp Bulb Replacement .......... 6-33
Fuel
.......................................... 6-3
Cage
....................................... 2-72
Fuse Block
Engine Coolant Temperature
.................... 2-66
Fuel
....................................... 2-72
Engine Oil Pressure ........................... 2-69
GasCap
....................................... 6-5
Gate A-jar Light ................................ 2-71
GAWR
....................................... 4-40
Gear
Positions ................................. 2-18
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Net. Convenience .............................. 2-46 Over Things That Burn ........................ 2-24
Neutral
....................................... 2-19 Passing ..................................... 4-12
New Vehicle “Break-In”
......................... 2- 13 Passlock’ ..................................... 2-12
Nightvision
................................... 4-27 Payload ....................................... 4-42
Normal Maintenance Replacement Parts
............. 6-6 1 Periodic Maintenance Inspections .................. 7-43
Power
Odometer
.................................... 2-6 1
Off-Road Driving .............................. 4- 15
Off-Road Recovery
............................. 4- I 1
OnStar System ................................ 2-57
Ordering Owner and Service Publications
....... 8- I 1, 8- 12
Outside Mirror
Power Remote Control
......................... 2-41
Convex ..................................... 2-42
Overhead Console
.............................. 2-42
Oil. Engine
.................................... 6-10
Accessory Outlets ............................ 2-52
DoorLocks
................................... 2-5
Remote Control Mirror
........................ 2-41
Seat
......................................... 1-2
Steering
..................................... 4-9
Steering Fluid
................................ 6-25
Windows
................................... 2-28
Pregnancy. Use of Safety Belts
.................... 1 . 19
Problems on the Road
............................ 5-1
Publications. Service and Owner .............. 8- 1 1. 8. 12
Overheating Engine
............................. 5- 1 1
Owner Checks and Services ....................... 7-39 Radiator. Adding Coolant ....................... 5-17
Owner Publications
........................ 8- I 1. 8- 12 Radiator Pressure Cap ........................... 6-24
Radio Reception
................................ 3-23
Paint Spotting. Chemical 6-52
Park
......................................... 2-18
Shifting Into 2-21
Shifting Out
of 2-23
AtNight
2-11
Brake ...................................... 2-20
Brake Mechanism Check 7-42
Lots ....................................... 2-11
On Hills with a Trailer 4-50
Radios ........................ Cassette Tape Player ........................... 3-8
Cassette Tape Player Care 3.24. 7.39
CDChanger 3-18
Compact Disc Player 3-12
Compact Disc Player Care 3-26
Rear Seat Audio
.............................. 3-16
Setting the Clock 3-8
Theft-Deterrent Feature
........................ 3-21
Rain. Driving 4-28
................. ................................. ................................. ............................... .......................... Parking ...................... ....................................
.............................. .......................
.................................. ......................... RAP ......................................... 2-15
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