Cooling System Pressure Cap

The cooling system pressure cap is located on the coolant outlet housing near the front of the cylinder head.
The cooling system will operate at higher than atmospheric pressure. The higher pressure raises the coolant boiling point, allowing increased radiator cooling capacity. The pressure cap will release cooling system pressure in a range of 97 - 124 kPa (14 - 18 psi).







A vent valve located in the center of the cap allows a small amount of coolant flow from the coolant reserve system (CRS) tank. This valve is spring loaded in the closed position. However, it must be free to open during system cool-down. If the valve is stuck shut, the radiator hoses will collapse on cool-down. Clean the vent valve to ensure proper sealing function.
There is a gasket in the cap that seals to the top of the filler neck so that vacuum is maintained to draw coolant back into the system from the coolant reserve system (CRS) tank.