I'm having over heating issues. My car runs at normal temp when driving but overheats at stops. I changed thermostat still overheats I took it to shop and noticed engine fan wasn't kicking on. Could this bee water pump failure? I tried to move the fan by hand it doesn't move is this normal? I put new radiator, fan clutch and fan blade in 1 year ago, due to fender bender. They think is a electric fan but the engine cooling fan is belt driven. I'm a chef and am not close to a mechanic all my car knowledge is mostly from this sight and Internet . My car is a 1979 280 e and has 250000 miles well maintained. I need help!!