Chrysler Repair: Caravan overheating, core tubes, radiator shop

Question
I have a Dodge 1996 2WD Caravan witn a 3.3L engine which is overheating.  The fans weren't kicking on.  I did some research, hotwired the fans (they worked) and replaced the fan relay.  Still not working.  I replaced the engine temp. sensor.  Now the fans come on when the engine heats up, but it still overheats two minutes later.  It seems that there is no coolant circulating to/through the radiator because it doesn't even get hot.  There is plenty of coolant in it.  I have replaced the thermostat too. Could this be a bad water pump?  Help!

Answer
Hi Craig,
It could be the water pump or more likely the radiator core tubes are partially/fully blocked, or the thermostat is stuck closed. So begin with the thermostat located in the manifold to which the top radiator hose is attached. You can remove it and see if it opens when you put it in a pan of heating water. It should open around 195F. If not, replace it. If it is the orginal radiator and you haven't been flushing it out that would be my second choice. Water pumps usually fail by leaking rather than failing to spin. But check the pulley on the pump to make sure the belt isn't so loose that it isn't turning responsively to the belt movement. If one side of the radiator is hot and the other side is cold, then that would be a good sign of poor/no circulation across the tubes. See if you can clean it out with a heavy duty cleaner or remove it and have a radiator shop clean it out.
Roland