My leyland daf 45 cooling system issue?

My Leyland daf lorry (2000 reg) runs and drives well. the temperature gauge is fairly steady indicating around 90 degrees. The in cab heater works well. However after driving the lorry I have noticed that the radiator is cold to the touch. I have found a slight water leak which I have repaired. The pipes leading to/from the radiator fell cold too. Any ideas if there actually is a fault or am I just imagining theres a problem