Grand Caravan FWD V6-229 3.8L VIN L MFI (1997)
Radiator Pressure Cap: Description and Operation
GENERAL INFORMATION
The radiator is equipped with a pressure cap that releases built up pressure, maintaining a range of 97 - 124 kPa (14 - 18 psi). The cooling system
will operate at higher than atmospheric pressure. The higher pressure raises the coolant boiling point thus, allowing increased radiator cooling
capacity.
VENT VALVE
There is also a vent valve in the center of the cap. This valve also opens when coolant is cooling and contracting allowing coolant to return to
radiator from coolant reserve system tank by vacuum through connecting hose. If valve is stuck shut, or the coolant recovery hose is pinched, the
radiator hoses will be collapsed on cool down. Clean the vent valve and inspect coolant recovery hose routing, to ensure proper sealing when
boiling point is reached.
GASKET
The gasket in the cap seals the filler neck, so that vacuum can be maintained, allowing coolant to be drawn back into the radiator from the reserve
tank.