1999 CADILLAC CATERA radiator cap

yellowblue
5-15
1. 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. Turn the pressure cap slowly
counterclockwise (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 pressure cap slowly, and
remove it.

yellowblue
5-16
3. Then fill the coolant surge tank with the proper
mixture, to the KALT/COLD line (seam).4. With 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
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 KALT/COLD line (seam).

yellowblue
6-20
Surge Tank Pressure Cap
NOTICE:
The surge tank cap is a 14 psi (97 kPa)
pressure
-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating.
If the surge tank pressure cap needs to be replaced, a
GM cap is recommended.
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.
If the thermostat needs to be replaced, a GM thermostat
is recommended.
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL
engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL
extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.

yellowblue
6-23
CAUTION:
Turning 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.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
KALT/COLD line (seam).
If the light comes on and
stays on, it means you're
low on engine coolant.
For more information, see ªLow Coolant Warning
Lightº in the Index.Adding Coolant
If you need more coolant, add the proper DEX
-COOL

coolant mixture at the surge tank, but only when the
engine is cool.
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.
When replacing the pressure cap, make sure it is
hand
-tight.