engine CHEVROLET SUBURBAN 1993 Workshop Manual

Pmbkms on the Road
If your vehicle has the four-wheel-drive option and the transfer case is
engaged,
a dolly must be used under the rear wheels when towing from the
front.
Engine Overheating
You will find a coolant temperature gage on your vehicle instrument panel,
If Steam Is Coming From Your Engine:
I
‘i Steam from an overheated engine can bum you badly, even if you
just open the hood. Stay away from the engine if you see or hear
steam coming from it. Just turn it off and get everyone away from
the vehide until it cools down. Wait until there is no sign of steam or
coalant before opening the hood.
If you keep driving when your engine is overheated, the liquids in it
can catch fire. You or others could be badly burned. Stop your
engine if it overheats, and get out of the vehicle until the engine is
Cool.
you keep driving with no coolant, your
costly repairs would not be covered
by
your warranty.
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If No Steam Is Coming From Your C gine:
If you get the overheat warning but see or hear no steam, the problem may
not be too serious. Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam, try this for a minute
or so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan speed and open the
3. If you’re in a traffic jam, shift to N (Neutral).
window
as necessary.
If you no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten minutes.
If the warning doesn’t come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your vehicle right away.
If there’s still no sign of steam, push the accelerator until the engine speed is
about twice as fast as normal idle speed. Bring the engine speed back to
normal idle speed after two or three minutes.
Now see if the warning stops.
But then,
if you still have the warning, TURN OFF THE ENGINE AND GET
EVERYONE
OUT OF THE VEHICLE until it cools down.
You may decide not
to lift the hood but to get service help right away.
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Cooling System
.i
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PO21 0
When you decide it's safe to lift the hood, here's what you'l\
l see:
A. Coolant recovery tank
B. Radiator pressure cap
C. Engine fan
A
An electric fan under the hood can start up even when the engine is
not running and can injure you. Keep hands, clothing, and tools
away from any underhood
electric fan.
CAUTION
If the coolant inside the coolant recovery tank or surge tank is \
boiling, don't
do anything else until it cools down.
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The coolant level should be at or above COLD. 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.
CAUTION
A
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, 1‘ it coulc
lose all coolant. That could cause an engine fire, and you could
be
I burned. Get any leak fixed before you drive the vehicle.
I
If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running. If the engine is overheating, the fan \
should be running.
If
it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
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 or above
COLD, add a 50150 mixture of clean water (preferably distilled) and a proper
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antifreeze at the coolant recovery tank. (See “Coolant” i\
n the Index for more information about the proper coolant mix.)
Adding only plain water to your cooling system can be dangerou\
s. 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 50150 mix of clean water and a proper antifreeze. I I
NOTICE I
In cold weather, water can freeze and crack the engine. radiator, heater
I core and other parts. Use the recommended coolant.
1
1 ::.
L.
k’
II
PO206
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
is at or above COLD, start your
vehicle.
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K2550
6. Start the engine and let it run until you can feel the upper radiator hose
getting hot. Watch out for the engine fan@).
7. By this time, the coolant level inside the radiator filler neck m\
ay 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.
1
K2515
8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the clutc\
h is engaged,
the fan spins faster
to provide more air to cool the engine. In most every day
driving conditions the clutch is not engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer towing \
and/or high
outside temperatures, the fan speed increases when the clutch e\
ngages.
So
you may hear an increase in fan noise. This is normal and sh\
ould 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 disengages.
You may also hear this fan noise when you start the engine. \
It will go away
as the fan clutch disengages.
If a Tire Goes Fiat
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 co\
ntrol 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 your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driving slowly to a
level place. Turn
on your hazard warning flashers.
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L
Changing a tire can cause an injury. The vehicle can slip off the jack
injured. Find a level place to change your tire. To help prevent the
vehicle
from moving:
- and roll over you or other people. You and they could be badly
1. Set the parking brake firmly.
2. Put the shift lever in P (Park).
3. Shift a manual transmission to 1 (First) or R (Reverse).
4. If you have a four-wheel-drive vehicle, be sure the transfer case \
5. Turn off the engine.
is in a drive gear-not in N (Neutral).
To be even more certain the vehicle won't move, you can put chocks
at the front and rear of the tire farthest away from the one being
changed. That would be the tire on the other side of the vehicle, at
the opposite end.
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The following steps will tell you how to use the jack and change a tire.
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K2143
If you have a utility model, use these locations.
Put the cover back on the tire if your vehicle has one.
Put the tire into the vehicle, over the bolt. Slide the adapter onto the bolt in
the proper location for your model, and put the wing nut on. Turn\
the wing
nut clockwise until the adapter is tight against the wheel, then close the
cover.
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. The method known as “rocking” can help you get o\
ut when you’re stuck, but you must use caution.
If you let your tires spin at high speed, they can explode and \
you or I
I-, others could be injured. And, the transmission or other parts of the
vehicle can overheat. That could cause an engine compartment fi\
re or other damage. When you’re stuck, spin the wheels as litt\
le as
possible. Don’t spin the wheels above
35 mph (55 kmlh) as shown
on the speedometer.
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Service & Appearance Care
.
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 ........................................................................\
................................................ 6-4
Checking Things Under the Hood
....................................................................... \
6-8
Hood Release
........................................................................\
............................ 6-8
Engine Oil ........................................................................\
.................................. 6-9
Air Cleaner
........................................................................\
............................... 6-16
Automatic Transmission Fluid
........................................................................\
. 6-17
Manual Transmission Fluid ........................................................................\
..... 6-20
Hydraulic Clutch
........................................................................\
....................... 6-21
Transfer Case
........................................................................\
.......................... 6-23
Front
Axle ........................................................................\
................................. 6-24
Rear Axle
........................................................................\
................................. 6-24
Engine Coolant
........................................................................\
........................ 6-25
Power Steering Fluid
........................................................................\
............... 6-29
Windshield Washer Fluid
........................................................................\
......... 6-31
Brake Master Cylinder
........................................................................\
............. 6-32
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