1994 GMC SIERRA radiator

1. You can remove the coolant surge tank pressure cap when the coolin\
g
system, including the coolant surge tank pressure cap and upper\

radiator hose, is no longer hot.
I
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.
2. Then keep
turning the cap,
but now push down as
you turn
it. Remove the
pressure cap.
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3. Open the air
bleed valve
located on the
thermostat
housing.
4. Fill the coolant
surge tank with
the proper mix,
up to the
COLD
mark.
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).
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I NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged.
The repair cost wouldn’t be covered by
your warranty.
Too much water in the mix can freeze and crack
the engine, 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 proper way to add
coolant.
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.
Adding Coolant -Gas Engines
To Check Coolant
The coolant recovery
tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
When your engine
is cold, the coolant level should be at COLD, or a little
higher. When
your engine is warm, the level should be up to HOT, or a little
higher.
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To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tunk.
A CAUTION:
Turning the radiator pressure cap when the engine and radiator
are hot can allow steam and scalding liquids to blow out and
burn you badly. With the coolant recovery tank, you will almost
never have to add coolant at the radiator. Never turn the
radiator pressure cap
- even a little - when the engine and
radiator are hot.
Add coolant mix at the recovery tank, but be careful not to spill it.
A 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.
Adding Coolant -Diesel Engines
The coolant surge tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
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To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark,
or a little higher. When your engine is warm, the level should be above the
COLD mark.
If this light comes on,
it means you’re low
on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix at the surge tnnk, but only
when the engine is cool.
Open the air bleed valve on the thermostat housing to allow trapped air
out
of the system. Close the bleed valve when coolant begins to flow out.
I A CAUTION:
nrning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow
out:
and burn you badly. Never turn the surge tank pressure cap -
even a little - when the engine and radiator are hot.
A 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.
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Radiator Pressure Cap-Gas Engines
The radiator pressure
cap must be tightly
installed with the
arrows
on the cap
lined
up with the
overflow tube
on the
radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa) pressure-type cap and
must be tightly installed to prevent coolant
loss and possible
engine damage from overheating. Be sure the arrows
on the cap
line
up with the overflow tube on the radiator filler neck.
Surge Tank Pressure Cap- Diesel Engines
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It must be tightly installed to prevent coolant
loss and possible
engine damage from overheating. Be sure the arrows on the cap
line up with the top tube
of the coolant surge tank.
Thermostat
Engine coolant temperature is controlled by a thermostat in the engine
coolant system. The thermostat stops
the flow of coolant through the
radiator
until the coolant reaches a preset temperature.
When
you replace your thermostat, an AC" thermostat is recommended.
Power Steering Fluid
NOTICE:
Always turn the engine off before checking or adding power
steering fluid. The power steering pump cap is close to the fan
and other moving parts.
How To Check Power Steering Fluid
Unscrew the cap and
wipe the dipstick
with
a clean rag. Replace
the cap and completely
tighten it. Then
remove the cap again
and
look at the fluid
level on the dipstick.
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Windshield Washer Fluid
To Add
Open the cap labeled
“WASHER FLUID
ONLY.” Add washer
fluid until
the bottle is
full.
NOTICE:
When using concentrated washer fluid, follow the
manufacturer’s instructions for adding water.
Don’t mix water with ready-to-use washer fluid. Water can
cause the solution to freeze and damage your washer fluid
tank and other parts of the washer system. Also, water
doesn’t clean as well as washer fluid.
Fill your washer fluid tank only 314 full when it’s very cold.
This allows for expansion, which could damage the tank if it is
completely full.
Don’t use radiator antifreeze in your windshield washer. It
can damage your washer system and paint.
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