LSS V6-3.8L VIN K (1997)
Radiator Cap: Description and Operation
DESCRIPTION
A pressure vent cap is used on the cross-flow radiator to allow a build up between 93 kPa - 124 kPa (13.5 psi - 18 psi) in the cooling system. This
pressure raises the boiling point of coolant to approximately 129°C (265°F) at sea level. Do not remove radiator cap to check engine coolant level;
check coolant visually at the see through coolant reservoir. Coolant should be added only to the reservoir.
WARNING: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature
of the solution in the radiator without causing the solution to boil. Removal of the radiator cap while the engine is hot and pressure is
high will cause the solution to boil instantaneously - possibly with explosive force - spewing the solution over engine, fenders, and person
removing cap. Under some conditions, the ethylene glycol in engine coolant is combustible.
The pressure-type radiator filler cap contains a blow-off (or pressure valve) and a vacuum (or atmospheric valve). The pressure valve is held
against its seat by a calibrated spring and protects the radiator by relieving any internal pressure exceeding design specification.
PURPOSE
The radiator cap is designed to prevent accidental removal. The finger grips have been removed so that the cap is round in shape. It must be
pushed downward before it can be removed. A rubber/asbestos gasket is added to the diaphragm spring at the top of the cap. Also, embossed on
the cap is a caution against its being opened and arrows indicating the proper closed position.
WARNING: If there is evidence of steam, do not open hood until steam is dispersed as bodily injury could occur.
