1993 GMC SIERRA coolant

Cooling System
PO21 0
When you decide it’s safe to lift the hood, here’s what you’ll see:
A. Coolant recovery tank
B. Radiator pressure cap
C. Engine fan
CAUTION
‘4
An electric fan under the hood can start up even when the engine\
is
not running and can injure you. Keep hands, clothing, and tool\
s
away from any electric fan.
m
If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until it cools down.
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I
I
‘4
!b P4
LL
1
PO593
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.
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 cou
lose all coolant. That could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the vehicle.
I I
NOTICE
Engine damage from running your engine without coolant isn’t covered by
I your warranty.
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 50hO mixture of clean water (preferably distilled) and a proper
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antifreeze at the coolant recovery tank. (See “Coolant” in the Index for more
information about the proper coolant mix.)
* 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
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
7 50/50 mix of clean water and a proper antifreeze.
I ln cold weather, water can freeze and crack the engine, radiator, heate\
r
:ore and other parts. Use the recommended coolant.
PO206
I * You can be burned if you spill coolant on hot engine parts. CoolQni
A contains ethylene glycol and it will burn if the engine parts are hut
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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If the overheat warning continues, there’s one more thing you c\
an try. You
can add the proper coolant mix directly to the radiator, but \
be sure the radiator is cool before you
do it.
‘ Steam and scalding liquids from a hot cooling system can blow \
out
I- and burn you badly. They are under pressure, and if you turn the
radiator pressure cap-even a little-they can come out at high
speed. Never turn the cap when the cooling system, including t\
he radiator pressure cap, is hot. Wait for the cooling system and\
radiator
pressure cap to cool
if you ever have to turn the pressure cap. I
. . . .
1
K2Jll
How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when the cooling system,
including the radiator 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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1
PO244
2. Then keep turning the pressure cap, but now push down as you turn it.
Remove the pressure cap.
K2341
3. Fill the radiator with the proper mix, up to the base of the filler neck.
4. Then fill the coolant recovery tank to COLD.
5. Put the cap back on the coolant recovery tank, but leave the \
radiator
pressure cap
off.
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Prob/ems on the Road
t
e;
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(s).
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 f\
iller
neck until the level reaches the base of the filler neck.
K2515
8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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Service & Appearance Care
Engine Coolant ........................................................................\
........................ 6-42
Power Steering Fluid
........................................................................\
............... 6-46
Windshield Washer Fluid
........................................................................\
......... 6-48
Brake Master Cylinder
........................................................................\
............. 6-49
Replacing Brake System Parts
........................................................................\
.. 6-50
Other Maintenance Items ........................................................................\
........... 6-51
Lubrication
........................................................................\
.................................... 6-52
Electrical System
........................................................................\
......................... 6-54
Battery
........................................................................\
...................................... 6-54
Fuses and Circuit Breakers
........................................................................\
.... 6-64
Bulb Replacement
........................................................................\
.................... 6-54
Exhaust System
........................................................................\
........................... 6-65
Loading Your Vehicle
........................................................................\
.................. 6-67
Tires
........................................................................\
.............................................. 6-72
Inflation-Tire Pressure
........................................................................\
........... 6-73
Tire Inspection and Rotation
........................................................................\
.. 6-78
When It's Time for New Tires
........................................................................\
6-80
Buying New Tires
........................................................................\
.................... 6-81
Wheel Alignment and Tire Balance
............................................................... 6-82
Wheel Replacement
........................................................................\
................. 6-83
Tire Chains
........................................................................\
............................... 6-84
Appearance Care
........................................................................\
........................ 6-84
Cleaning the Inside Of Your Vehicle
............................................................. 6-85
Cleaning the Outside Of Your Vehicle
.......................................................... 6-88
Appearance Care Materials
.r.ikl...rr.r.n.....lr. ........ ... .. 6-91
Vehicle Identification Number
........................................................................\
..... 6-92
Service Parts Identification Label
...................................................................... 6-94
Specification Charts
....++t....,.,.*,..-".,,. .............. , ........... .................... 6-95
Uniform Tire Quality Grading
........................................................................\
.. 6-81
..................................................
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Service & Appearance Cam
i r:
PO21 7
If your vehicle has air conditioning, the auxiliary fan under the \
hood
can start up and injure you even when the engine is not runn\
ing.
Keep your hands, clothing and tools away from any underhood
electric fan,
if you have one.
Things that burn can get on hot engine parts and start
a fire. These
b include liquids like gasoline or diesel fuel, oil, coolant, bra\
ke fluid,
windshield washer and other fluids, and plastic or rubber. You or
others could be burned. Be careful not
to drop or spill things that will
burn onto a hot engine.
Before closing the hood, be sure all the filler caps are
on properly. Then just
pull the hood down and close it firmly.
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