engine coolant BUICK RANDEZVOUS 2004 User Guide

What Coolant to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOL®coolant which won’t damage
aluminum parts. If you use this coolant mixture,
you don’t need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice: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.
Checking Coolant
The coolant recovery tankr
is located on the driver’s
side of the vehicle, above
the engine air cleaner/lter.
SeeEngine Compartment
Overview on page 5-12for
more information on
location.
5-24

The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark, or a little higher. When your engine is
warm, the level should be above the FULL COLD mark
or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixtureat the coolant recovery tank.
{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 mixture at the recovery tank, but be careful
not to spill it.
{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.
Occasionally check the coolant level in the radiator. For
information on how to add coolant to the radiator,
seeCooling System on page 5-29.
Radiator Pressure Cap
Notice:The radiator cap on your vehicle is a
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 overow tube on the radiator ller
neck.
The radiator pressure cap is located at the front of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location.
5-25

Engine Overheating
You will nd an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-46. You also have
an engine coolant temperature warning message on
your instrument panel. SeeEngine Coolant Temperature
Warning Message on page 3-51.
Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to
be driven to a safe place in an emergency situation.
If an overheated engine condition exists, an overheatprotection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode,
you will notice a signicant loss in power and engine
performance. The temperature gage will indicate
an overheat condition exists. Driving extended miles
(km) and/or towing a trailer in the overheat protection
mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. See “Engine Oil” in the Index.
5-26

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
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 vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
See “Overheated Engine Protection Operating
Mode” in the Index for information on driving
to a safe place in an emergency.
Notice:If your engine catches re because you keep
driving with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered by
your warranty. See “Overheated Engine Protection
Operating Mode” in the Index for information on
driving to a safe place in an emergency.
5-27

Cooling System
When you decide it is safe to lift the hood, here’s what
you will see:
A. Radiator Pressure Cap
B. Electric Engine Cooling Fans
C. Coolant Recovery Tank{CAUTION:
An electric engine cooling 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.
If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.
5-29

The coolant level should be at or above the full cold
mark. If it is not, you may have a leak at the pressure
cap or in the radiator hoses, heater hoses, radiator,
water pump or somewhere else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.Notice:Engine damage from running your engine
without coolant isn’t covered by your warranty.
See “Overheated Engine Protection Operating
Mode” in the Index for information on driving to a
safe place in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-30

How to Add Coolant to the Coolant
Recovery Tank
If you have not found a problem yet, but the coolant
level is not at or above the full cold mark, add a 50/50
mixture ofclean, drinkable waterand DEX-COOL
®
engine coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-23for more information.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{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. Do not spill coolant on a hot engine.
5-31

How to Add Coolant to the Radiator
Notice:Your engine has a specic radiator
ll procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
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 counterclockwise until
it rst stops. Do not 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 pressure cap, but now push
down as you turn it. Remove the pressure cap.
{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. Do not spill coolant on a hot engine.
5-33

3. After the engine cools, open the coolant air bleed
valves.
There are two bleed valves. One is located on the
thermostat housing. The other is located on the
thermostat bypass tube.4. Fill the radiator with the proper DEX-COOL
®
coolant mixture, up to the base of the ller
neck. SeeEngine Coolant on page 5-23for more
information about the proper coolant mixture.
If you see a stream of coolant coming from an air
bleed valve, close the valve. Otherwise, close
the valves after the radiator is lled.
5. Rinse or wipe any spilled coolant from the engine
and the compartment. Housing
Bypass Tube
5-34

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
7. By this time, the coolant level inside the radiator
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches
the base of the ller neck.8. Then replace the pressure cap. At any time during
this procedure if coolant begins to ow out of the
ller neck, reinstall the pressure cap. Be sure
the arrows on the pressure cap line up like this.
5-35