System

DESCRIPTION
This vehicle has a pressure-type engine cooling system with thermostatic control of coolant circulation. The cooling system is sealed by a pressure-type radiator cap that causes the system to operate at higher than atmospheric pressure. The high-pressure operation raises the boiling point of the coolant, thereby increasing the cooling efficiency of the radiator. The 103 kPa (15 psi) pressure cap raises the boiling point of the coolant to about 128°C (262°F) at sea level.

OPERATION
The pressure-vacuum valve radiator cap allows the coolant to expand through the pressure valve in the center of the cap without building unnecessary pressure. The expanding coolant flows into the coolant recovery reservoir. The vent valve closes due to expansion and coolant flow. The nominal 103 kPa (15 psi) pressure will not be reached until the system is working at maximum capacity. Any air in the cooling system will be-forced into the coolant reservoir and out the vent tube at the top of the reservoir. As the system cools, the coolant in the reservoir is drawn back into the radiator through the vent valve. Through this process, the radiator remains full at all times.