1995 GMC SIERRA engine

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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NOTICE:
In cold weather, water can freeze and crack the engine, radiator,
heater core and other parts.
So use the recommended coolant.
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.
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 to the left
until it first stops. (Don't press down while turning the pressure cap.)
If you hear a hiss, wait for that to stop. A hiss means there is still some
pressure left.
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2. Then keep
turning the cap,
but now push
down as
you turn
it. Remove the
pressure cap.
3. After the engine
cools, open the
air bleed valve on
the thermostat
housing.
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.
4. Fill with the proper mix. Add coolant until you see a steady stream of
coolant coming from the bleed valve.
5. Close the bleed valve.
6. Rinse or wipe the spilled coolant from the engine and compartment.
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-
7. Then fill the
coolant surg,e
tank with the
proper
mix. up to
the COLD mark.
8. 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 fan(s).
By this time, the coolant level inside the coolant surge tank may be
lower. If the level is lower, add more of the proper mix to the coolant
surge tank until the level reaches
the COLD mark.
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Engine Fan Noise
Your 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 every day
driving conditions the fan is spinning slower and the clutch is
not fully
engaged. This improves fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside temperatures, the fan
speed increases as the clutch more fully 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 partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the
fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out
of a tire, it’s much more likely to
leak out slowly. But if you should ever have a “blowout,” here are a few tips
about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot
off the accelerator pedal and grip the
steering wheel firmly, Steer
to maintain lane position, then gently brake to a
stop well out of
the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your
foot from the accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well
off the road if
possible.
If a tire goes flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
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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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You should keep a record with all parts receipts and list the mileage and the
date
of any service work you perform. See “Maintenance Record” in the
Index.
A CAUTION:
You can be injured if you try to do service work on a vehicle
without knowing enough about it,
Be sure you have sufficient knowledge, experience, and the
proper replacement parts and tools before you attempt
any
vehicle maintenance task.
Be sure to use the proper nuts, bolts and other fasteners,
“English” and “metric” fasteners can be easily confused. If
you use the wrong fasteners, parts can later break or fall
off.
You could be hurt.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel Requirements and Fuel
System”
in this Section. For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at 87 octane or higher. It should meet
specifications ASTM D48
14 in the United States and CGSB 3.5-92 in
Canada. These fuels should have the proper additives, so you should not
have to add anything
to the fuel.
In the United States and Canada, it’s easy to be sure
you get the right kind
of gasoline (unleaded). You’ll see UNLEADED right on the pump. And
only unleaded nozzles will
fit into your vehicle’s filler neck.
Be sure the posted octane is at least
87. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If it’s bad enough,
it can
damage your engine.
If you’re using fuel rated at 87 octane or higher and you still hear heavy
knocking, your engine needs service. But don’t worry
if you hear a little
pinging noise when you’re accelerating or driving up a hill. That’s normal
and you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the
heavy, constant knock that means you have a problem.
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