engine overheat GMC SIERRA 1995 User Guide

I A 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.
I NOTICE:
Engine damage from running your engine without coolant isn’t
covered by your warranty.
If there seems to be no leak, start the engine again. See if the 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 Surge Tank
I NOTICE:
The diesel engine has a specific coolant fill procedure. Failure to
follow this procedure could cause your engine to overheat and be
severely damaged.
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark, add a
50/50 mixture of cleun water (preferably distilled) and a proper
antifreeze 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”
in the Index for more information about the proper
coolant mix.)
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A 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.
A CAUTION:
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 mix
will. Your vehicle’s coolant
warning system is set for the proper coolant mix. With plain
water
or the wrong mix, 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 mix of clean
water and a proper antifreeze.
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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 nlust 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 par\
ts
of the vehicle can overheat. That could cause an engine
compartment fire or other damage. When you’re stuck, spin th\
e 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.
Rocking
your vehicle to get it out:
First. turn your steering wheel left and right. That will clear the area around
your front wheels. Then shift back and forth between REVERSE
(R) and a
forward gear (or
with a manual transmission, between FIRST (1 ) or
SECOND (2) gear and REVERSE), spinning the wheels as little as possible.
Release
the accelerator pedal while you shift, and press lightly on the
accelerator pedal when the transmission
is in gear. If that doesn’t get you
out after a few tries, you may need
to be towed out. Or, you can use your
recovery hooks,
if your vehicle has them. If you do need to be towed out.
see “Towing Your Vehicle”
in the Index.
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NOTICE:
If there is water in your diesel fuel and the weather is warm or
humid, fungus and bacteria can grow in the fuel. They can
damage your fuel system. You'll need a diesel fuel biocide to
sterilize your fuel system. Your dealer can advise
you if you ever
need this.
If your fuel tank needs to be purged to remove water, see your
dealer or a qualified technician. Improper purging can damage
your fuel system.
Running Out of Fuel (Diesel Engines)
If the engine stalls and you think that you've run out of fuel, do this:
First, open the fuel filter air bleed valve.
Briefly crank the
engine and have
someone watch the
bleed valve. If there is
air, then you are
probably
out of fuel.
To restart your engine:
I. If you're parked on a level surface, add at least two gallons of fuel.
However, if you're parked
on a slope, you may need to add up to five
gallons of fuel.
2. With the air bleed valve open, turn your ignition key to START for 10
to
15 seconds to crank (but not start) your engine. Wait one minute
between intervals
of cranking to allow the starter motor to cool.
Overheating the starter motor could damage it. Keep doing this until
you can just see some clear fuel at the air bleed valve. (If, during this
step, the engine starts, turn the ignition off and close the valve before
restart.)
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If the differential is at operating temperature (warm), add enough lubricant
to raise the level to the bottom
of the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to
1/2 inch
( 12 mm) below 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 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.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
What to Use
Use a mixture of one-half cleun water (preferably distilled) and one-half
antifreeze that meets “GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M.” Use GM Coolant Supplement (Sealer) with a
complete coolant flush and refill. If you use this mixture. you don’t need to
add anything else.
A CAUTION:
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 mix will. Your vehicle’s coolant
warning system
is set for the proper coolant mix. With plain
water or the wrong mix, 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 mix of clean
water and
a proper antifreeze.
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NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged. The repair cost wouldn’t be covered by
your warranty.
Too much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions. such as air trapped
in the cooling system. can affect the
coolant level
in thc radiator. Check the coolant level when the engine is cold
and
follow the steps under “Adding Coolant“ for the proper way to add
coolant.
If you have to add coolant more than lour timcs a ycar, 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.
Adding Coolant - Gasoline Engine
The coolant reco\wy
tank is located on the
passenger side
at the
rear comer
of the
engine compartment.
To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher. When your engine is warm, the level should be up to the
HOT mark, or a little higher.
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To Check Coolant
A 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.
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher.
If this light comes on, it means you’re low on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tmk, but only
when the engine is cool. If the surge tank is empty, see “Engine
Overheating”
in the Index for the proper fill procedure.
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 replacing the pressure cap, make sure it is tight.
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Radiator Pressure Cap - Gasoline Engine
The radiator pressure
cap must be tightly
installed with
the
arrows on the cap
lined up with the
overflow tube on the
radiator filler neck.
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.
Surge Tank Pressure Cap - Diesel Engine
The surge tank
pressure cap must be
tightly installed with
the arrows on the cap
lined up with the top
tube of the coolant
surge tank.
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It 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 top tube of the coolant surge tank.
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine
coolant system. The thermostat stops the flow
of coolant through the
radiator until the coolant reaches a preset temperature.
When you replace your thermostat, an AC@ thermostat is recommended.
Power Steering Fluid
How To Check Power Steering Fluid
When the engine compartment is cool, unscrew the cap and wipe \
the
dipstick with a clean rag. Replace the cap and completely tighten it. Then
remove the cap again and look at the fluid level on the dips\
tick.
The level should be at the
FULL COLD mark. Add enough fluid to bring
the level
up to the mark.
A fluid loss in this system could indicate a problem. Have the system
inspected and repaired.
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Engine (continued)
Coolant
..................................................... 6-35
Coolant Heater
...................................... 2.18.3-4. 6.21
Coolant Temperature Gage (See “Gages”)
Control Module System
........................................ 6-57
Diesel Heater Output
............................................ 34
Exhaust
..................................................... 2-32
FanNoise
................................................... 5-25
Identification
....................................... 6-76,677, 6-81
Oil (See “Oil”)
Overheating
.................................................. 5-10
RunningWhileParked
......................................... 2-32
Starting Your Gasoline Engine
................................... 2-12
Starting Your Diesel Engine
..................................... 2-14
Exhaustsystem
................................................. 6-56
F
Filter Replacement Chart (See “Service-Replacement Parts and Filter
Recommendations”)
FinishDamage
.................................................. 6-74
Fluid Capacities (See “Capacities and Specification”)
FluidLeakCheck
................................................ 646
Fluids (See “Scheduled Maintenance Services”)
Fog Lamps (See “Lamps-Fog”)
Four-WheelDrive
.......................................... 2-33, 6-33
Front Axle Locking Feature
..................................... 2-36
Transfer Case
........................................... 2-34, 6-33
Canadian
...................................................... 6-5
Diesel
....................................................... 6-3
FillingYourTank
............................................. 6-11
Fuel
Foreign Countries (Gasoline Engines)
............................. 6-11
Filter Replacement (Diesel Engines)
............................... 6-9
Gage (See “Gages”)
Gasoline
..................................................... 6-2
Gasolines for Cleaner Air
........................................ 6-3
Running Out of Fuel (Diesel Engines)
.............................. 6-8
Tankcapacity
................................................ 6-83
Water in Fuel (Diesel Engines)
............................... 2-74, 6-5
Fuses and Circuit Breakers ................................... 6-79, 6-87
FuseBlock
............................................. 6-80, 6-86
G
Gages Engine Coolant Temperature Gage
................................ 2-80
Oil Pressure Gage
............................................. 2-81
Tamper Resistant Odometer ..................................... 2-69
Trip Odometer
................................................ 2-69
FuelGage
................................................... 2-79
Speedometer
................................................. 2-69
Tachometer
.................................................. 2-70
Voltmeter
.................................................... 2-82
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