Dodge Repair: 03 3.9L Dakota: coolant not circulating


Question
I have a 2003 Dodge Dakota 4wd V6 3.9L I have changed water pump flushed out radiator replaced thermostat and radiator cap and is still over heating the coolant is not circulating I'm going crazy I don't know what it could be unless I got a bad thermostat or water pump. O also before I changed the water pump the heater was working now its only blowing cold are please HELP

Answer
Hi Jessica,
I do have the manual for the '04 Dakota which shows a 3.7 and 4.7L engine, rather than the 3.9L that you have. However, if the 3.9L is based upon the 4.7L then there may be an explanation for your problem...air trapped in the system when it was refilled. The manual shows that at the front of the engine, where the upper radiator hose attaches to the inlet housing, that there is a bleed valve which is basically a removable plug. When the system has been drained, you begin the refill procedure with that screw plug removed and then add coolant to the radiator until it reaches the opening of the bleed valve. You then re-insert the screw plug, and then continue to fill the radiator to the top and put on the radiator cap. Finally fill the overflow bottle to the 'full' line. Then operate the engine till it warms up, then let it cool, then recheck the level in the overflow bottle.
Let me know if this is what you find to be the case for your 3.9L engine.
Please read the PS below and respond to it.
Thanks,
Roland