1994 CHEVROLET SUBURBAN engine

6. 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 radiator filler neck may be
lower.
If the level is lower, add more of the proper mix through the
filler neck
until the level reaches the base of the filler neck.
8. Then replace the
pressure cap. At
any time during
this procedure
if
coolant begins to
flow out of the
filler neck,
reinstall the
pressure cap. Be
sure the arrows
on pressure cap
line up
like this.
Cooling System -Diesel Engines
When you decide it's
safe
to lift the hood,
here's what
you'll see:
A
A. Coolant surge
tank pressure cap
B. Engine fan(s)
C. Radiator
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If the coolant inside the coolant surge tank is boiling, don't do anything else
until it cools down.
The coolant level
should be at
or above
the
COLD mark. If it
isn't, you may have
a
leak in the radiator
hoses, heater hoses,
radiator, water
pump
or somewhere else in
the cooling system.
NOTICE:
Engine damage from running your engine without coolant isn't
covered by your warranty.
If there seems to be no leak, start the engifie 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.
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How to Add Coolant to the Coolant Surge Tank
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark add a 50/50 mixture of clean 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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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.
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While filling the surge tank, watch to see if coolant begins to stream out
the air bleed valve. When coolant begins to stream out, close the valve.
5. With the air bleed
valve closed and
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).
6. 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.
7. Then replace the
pressure cap.
Be
sure the arrows
on the pressure
cap line up like
this.
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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 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 section shows how to use your jacking equipment
to change a flat tire safely.
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Service & Appearance
I Section
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information
about your vehicle. and a section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
............................
Diesel Fuel Requirements and Fuel System ..........
Checking Things Under the Hood ........... .....
........ 6-4
.......... 6-5
......... 6-14
HoodRelease
.......................................... 6-14
Cleaning Your Diesel Engine
............................ 6-15
Engine Oil (Except Diesel)
................................ 6-16
Engine Oil (Diesel Engines)
............................... 6-22
Aircleaner
.................... .................. 6-27 ..
Automatic Transmission Fluid ............................. 6-28
Manual Transmission Fluid
............................... 6-31
Hydraulic Clutch
........................................ 6-32
RearAxle
............................................. 6-33
Transfer Case
.......................................... 6-34
FrontAxle
........................................... 6-35
Engine Coolant
......................................... 6-35
Power Steering Fluid
.............. .................. 640
Windshield Washer Fluid
............................... 6-42
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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
D4814 in the U.S. 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 U.S. 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.
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.
Methanol 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.
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