2006 BUICK LUCERNE radiator cap

If the overheat warning continues, there is one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system is cool before you do it.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out 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 the 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.
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 counterclockwise.
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. Remove the
pressure cap.
3. Remove the 3800 Series II V6 engine cover shield
to access the bleed valve.
5-32

3.1. Clean the area around the engine oil ll tube
and cap before removing. Twist the oil ll
tube, with cap attached, counterclockwise
and remove it.
3.2. Lift the engine cover shield at the front, slide
the catch tab out of the engine bracket and
remove the cover shield.
3.3. Put the oil ll tube, with cap attached, in the
valve cover oil ll hole until you are ready to
replace the cover shield.4. After the engine cools,
open the coolant air
bleed valve. There
is one bleed valve. It is
located on the
thermostat housing.
5. Fill the radiator with the proper DEX-COOL
®coolant
mixture, up to the base of the ller neck. See
Engine 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 valve after the radiator is lled.
6. Rinse or wipe any spilled coolant from the engine
and the compartment.
7. Replace the 3800 Series II V6 engine cover shield.
7.1. Remove the oil ll tube, with cap attached,
from the valve cover.
7.2. Insert the catch tab on the cover shield
under the bracket on the engine.
7.3. Place the hole in the cover shield over the
hole in the valve cover. Install oil ll tube and
cap by twisting clockwise.
5-33

8. Then ll the coolant recovery tank to the FULL
COLD mark.
9. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
10. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
11. 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.
12. 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 arrow on the pressure cap lines up properly.
Cooling System (4.6L V8 Engine)
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank with Pressure Cap
B. Electric Engine Cooling Fans
5-34

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.
You can remove the coolant surge tank pressure cap
when the cooling system, including the coolant
surge tank pressure cap and upper radiator hose, is no
longer hot.1. Turn the pressure cap slowly counterclockwise. 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 and remove it.
3. Fill the coolant surge
tank with the proper
mixture to the
FULL COLD mark on
the side of the
coolant surge tank.
4. With the coolant surge tank cap off, start the engine
and let it run until you can feel the upper radiator
hose getting hot. Watch out for the engine
cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark on
the side of the coolant surge tank.
5. Then replace the cap. Be sure the cap is hand-tight
and fully seated.
5-37

Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Engine cooling system service
(or every ve years, whichever occurs
rst).An Emission Control Service. See
footnote (j).•
Inspect engine accessory drive belt.
An Emission Control Service. See
footnote (n).•
Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts or
signs of wear. Inspect power steering lines and hoses
for proper hook-up, binding, leaks, cracks, chang, etc.
(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
ttings and clamps; replace with genuine GM parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
6-7

(d)Visually inspect wiper blades for wear or cracking.
Replace wiper blades that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors, and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken airbag
coverings, and have them repaired or replaced.
The airbag system does not need regular maintenance.
(f)Lubricate all key lock cylinders. Lubricate all
hinges and latches, including those for the hood, rear
compartment, glove box door, and console door.
More frequent lubrication may be required when
exposed to a corrosive environment. Applying silicone
grease on weatherstrips with a clean cloth will make
them last longer, seal better, and not stick or squeak.
(g)If you drive regularly under dusty conditions, the lter
may require replacement more often.(h)Change automatic transaxle uid and lter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(j)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer perform
this service. See Engine Coolant on page 5-23 for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap, and ller neck. Pressure test the
cooling system and pressure cap.
(k)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.
(l)Inspect throttle body bore and valve plates for
deposits. Open the throttle valve and inspect all
surfaces. Clean as required.
(m)If you drive regularly under dusty conditions, inspect
the lter at each engine oil change.
(n)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8

Power (cont.)
Inadvertent Battery Saver.............................3-18
Lumbar Controls........................................... 1-3
Retained Accessory (RAP)............................2-22
Seat ............................................................ 1-2
Steering Fluid.............................................5-38
Windows....................................................2-17
Pretensioners, Safety Belt................................1-29
Programmable Automatic Door Locks.................2-13
Q
Questions and Answers About Safety Belts.........1-15
R
Radiator Pressure Cap....................................5-27
Radios..........................................................3-74
Care of Your CD Player..............................3-101
Care of Your CDs ......................................3-100
Navigation/Radio System,
see Navigation Manual..............................3-98
Radio with CD....................................3-77, 3-82
Setting the Time..................................3-75, 3-76
Theft-Deterrent............................................3-98
Understanding Reception............................3-100
Rainsense™ II Wipers....................................... 3-9Rear Door Security Locks................................2-13
Rear Safety Belt Comfort Guides......................1-27
Rear Seat Armrest..........................................2-46
Rear Seat Passengers, Safety Belts..................1-25
Rearview Mirror, Automatic Dimming..................2-33
Rearview Mirror, Automatic Dimming with
Compass....................................................2-33
Rearview Mirror with Compass and
Temperature...............................................1-10
Rearview Mirrors.............................................2-33
Reclining Seatbacks.......................................... 1-6
Recommended Fluids and Lubricants.................6-12
Recreational Vehicle Towing.............................4-34
Remote Keyless Entry System............................ 2-5
Remote Keyless Entry System, Operation............ 2-6
Removing the Flat Tire and Installing the
Spare Tire..................................................5-75
Removing the Spare Tire and Tools...................5-74
Replacement Bulbs.........................................5-55
Reporting Safety Defects
Canadian Government..................................7-14
General Motors...........................................7-14
United States Government............................7-13
Restraint System Check
Checking the Restraint Systems....................1-69
Replacing Restraint System Parts
After a Crash..........................................1-70
10