1995 CHEVROLET SUBURBAN engine

NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or,
heater core and other parts.
So use the recommended coolant.
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.
4. Fill with the proper mix. Add coolant until you see a steady stream of
5. Close the bleed valve. coolant coming
from the bleed valve.
6. Rinse or wipe the spilled coolant from the engine and compartment.
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7. Then fill the coolant
surge
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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h
9. Then replace the
pressure cap. Be
sure the arrows
on the pressure
cap line up like
this.
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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You should keep a record with all parts receipts and list the mileage and the
date
of any servi-work you perform. See “Maintenance Record” in the
Index.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains the
maintenance your
new vehicle needs, and when it should be done. It also
has a form that
you can use to record the maintenance work done on your
vehicle. Be sure
to read this information.
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.
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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.
What about gasoline
with blending materials that contain oxygen
(oxygenates), such as MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.’’ Fuel that is no more than 15%.
MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel that is no more than
10% ethanol is fine for your vehicle.
Methnrzol is methyl or wood alcohol.
~
NOTICE:
Fuel that is more than 5% methanol is bad for your vehicle.
Don’t use it.
It can corrode metal parts in your fuel system and
also damage plastic and rubber parts. That damage wouldn’t be
covered under your warranty. And even at
5% or less, there
must be “cosolvents” and corrosion preventers in this fuel to
help avoid these problems.
Gasolines for Cleaner Air
Your use of gasoline with deposit control additives will help prevent
deposits from forming
in your engine and fuel system. That helps keep your
engine
in tune and your emission control system working properly. It’s good
for
your vehicle, and you’ll be doing your part for cleaner air.
Many gasolines are now blended with oxygenates. General Motors
recommends that you use gasolines with these blending materials, such as
MTBE and ethanol. By doing so,
you can help clean the air, especially in
those parts of the country that have high carbon monoxide levels.
In addition, some gasoline suppliers are now producing reformulated
gasolines. These gasolines are specially designed
to reduce vehicle
emissions. General Motors recommends that
you use reformulated gasoline.
By doing
so, you can help clean the air, especially in those parts of the
country that have high ozone levels.
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You should ask your service station operators if their gasolines contain
deposit control additives and oxygenates, and
if they have been
reformulated
to reduce vehicle emissions.
Diesel Fuel Requirements and Fuel System
Some states and provinces have restrictions on the purchase of diesel fuel
for light-duty vehicles and require you
to buy permits or pay special taxes.
Some
of these restrictions apply only to residents, and others apply to both
residents and visitors. These restrictions can change.
To learn the current
restrictions
in any state or province, contact your auto club, the police or
other officials.
Fuel Requirements
NOTICE:
Diesel fuel or fuel additives not recommended in this manual
could damage your fuel system and engine. Your warranty
wouldn’t cover this damage. And:
Diesel fuel that has been mixed with engine oil could damage
your engine and emission controls.
Always check with your
service station operator to make sure his diesel fuel has not \
been mixed with engine oil.
If you ever run out of diesel fuel, it can be difficult to restart
your engine. “Running Out
of Fuel,” later in this section, tells
you how to get it started again.
To avoid all this, try never to
let your tank get empty.
What Fuel to Use
For best results, use Number 2-D diesel fuel year-round (above and below
freezing conditions) as
oil companies blend Number 2-D fuel to address
climate differences. Number 1-D diesel fuel may be used
in very cold
temperatures (when it stays below
0°F or -1 8°C); however, it will produce
a power and fuel economy
loss. The use of Number 1-D diesel fuel in warm
or hot climates may result in stalling, poor starting when the engine
is hot
and may damage the fuel injection system.
Diesel fuel may foam when you fill your tank. This can cause the automatic
pump nozzle
to shut off, even though your tank isn’t full. If this happens,
just wait for the foaming
to stop and then continue to fill your tank.
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Canadian Fuels
Diesel-powered trucks are now equipped with emission control systems that
require the use of diesel fuel with low-sulfur
(.05% by weight) content.
Both low- and higher-sulfur fuels will be available
in Canada. Only
low-sulfur diesel fuels are available
in the United States. It is important that
diesel-powered trucks are refueled with low-sulfur fuel. Use of fuels with
higher-sulfur content will affect the function
of the emission components
and may cause reduced performance, excessive smoke and unpleasant odor.
Cold Weather Operation
Follow the instructions listed previously under the heading “What Fuel to
Use
.”
If you’re driving in very cold temperatures and can’t get a “winterized”
Number
2-D that has been adapted to cold weather or a Number 1-D, you
can use one gallon of kerosene for every two gallons of diesel fuel. Once
you add the kerosene, run your engine for several minutes
so the fuels will
mix. Add kerosene only when
the temperature fills below 0°F (-I 8”C),
because the fuel economy of kerosene isn’t as good as that of diesel fuel.
I NOTICE:
Never use home heating oil or gasoline in your diesel engine.
They can cause engine damage.
In cold weather, your fuel filter may become clogged (waxed). To unclog it,
warm the filter to between 32°F and 50°F (0°C to 10°C). You won’t need
to replace it.
Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen if a service station doesn’t regularly inspect and clean
its fuel tanks, or if it gets contaminated fuel from its suppliers.
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