The device has a valve including a closure member 344V that opens and closes in response to a temperature of
coolant flowing through the device. When moving from a closed position to an open position, the member moves in a direction downstream of the direction of
coolant flow through the device. A vehicle engine cooling
system comprising the device is also claimed. When claimed as part of the vehicle engine cooling
system, the device additionally comprises a first inlet 341 connected to a
cylinder head of the engine, a second inlet 342 connected to a
cylinder block of the engine, a first outlet 343 connected to a radiator bypass conduit and a second outlet 344 connected to a radiator, whereby the valve is associated with the second outlet. The closure member may automatically open when a pressure differential across the valve exceeds a predetermined value. The
system may include a variable speed
coolant pump controlled based upon at least one vehicle operating parameter, such as the temperature of coolant, engine / transmission oil, or engine speed, that pumps coolant in the system at two different non-zero rates, the higher rate causing opening of the valve. A method is also claimed.