Puzzling overheating?

I have a 98 Ford Taurus SE with a 3.0, 24 valve v6. Here is the puzzle, the radiator and overflow are full of water to their proper levels. Oil is at its proper level. The fan comes on as it should when engine gets warm. However the car continues to overheat and overflow coolant. Engine runs quiet, no misses or rod noise. The exhaust is clean, no blue or black smoke. Does any one have any Ideas as to the problem I am having and how to solve it?

The problem might be with a restricted radiator. The radiator is a simple heat exchanger. If not enough coolant can pass thru the radiator to remove the engine heat the heat has nowhere to go. So the engine overheats.


You may have a sticking thermostat or a partially plugged radiator or a collapsed rad hose.

If after those suspects are eliminated and you still have an overheating problem, you may have the beginnings of a leaking head gasket. Keep an eye on the exhaust when the engine overheats.

I wouldn’t let this problem continue as overheating can cause cylinder head warpage among other unforseen problems.

The vehicle is 11 years old, and I assume that the water pump, thermostat and radiator hoses have not been replaced. I would suspect all of these.

I believe the 3.0 Duratec engine water pump Impeller is plastic. Its possible the Impeller has broken of the shaft, and this wouldn’t be the first time. However if this is the case the car would overheat very quickly, with no heat coming out the heater, because of no coolant flow whatsoever.