Hi everybody ! I have a '77 w123 240D and it has an oil cooling radiator . Only problem is that it is cold all the time . My question is : does the oil pass through the cooler all the time , pushed by the pump , or is there some sort of thermostat ? The cooler is cold even after city driving ... Can anyone tell me how the oil is circulating , and if i should be worried about the cooler being cloggeg or something ?