1993 GMC SIERRA radiator

When using concentrated washer flui
follow the manufacturer’s
instructions for adding water.
Don’t mix water with ready-to-use washer fluid. Water can ca\
use the
solution
to freeze and damage your washer fluid tank and other parts
of the washer system.
Also, water dc ;n’t clean as well as washer
fluid.
allows for expansion, which could damage the tank
if it is completely
full.
’
I
Fill your washer fluid tank only 314 full when it’s very cold. This
Don’t use radiator antifreeze in your windshield washer. It can
damaae your washer system and paint.
Cruise Control (Option)
K2247
With Cruise Control, you can maintain a speed of about 25 mph (40 km/h) or
more without keeping your foot on the accelerator. This can re\
ally help on
long trips. Cruise Control does not work at speeds below about 25 mph
(40 km/h).
When you apply your brakes, or push the clutch pedal, if you \
have
a manual
transmission, the Cruise Control shuts
off.
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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.
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8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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1 CAUTION
4 Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before th(
)per 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.
NOTICE
If you use an improper coolant mix, your engine could overheat an\
d 1:
badly damaged. The repair cost wouldn’t be covered by your warranty. 1
much water in the mix can freeze and xk +?e t line radiator, heater
core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to add
coolant.
If you have the low coolant warning system, refer to the General Motors
Service Manual or see your dealer for the proper coolant
fill procedure. (To
purchase a Service Manual, see “Service Publications’’ in the Index.) Using
the wrong
fill procedure can cause a low coolant warning indication.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
If you use the proper coolant, you don’t have to add extra inhibitors or
additives which claim to improve
the system. These can be harmful.
-
NOTICE .I
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