Causes include a plugged radiator, low coolant, air pocket in cooling system, failed head gasket, warped or cracked cylinder head.
Try the rad. fan or the rad. fan relay
Assuming it did not overheat before you replaced thermostat and water pump you may have installed the thermostat backwards. It is also possible the cooling system wasn't refilled properly and was air bound.
I have the same problem and I think that I have found out that the radiator is too small for the size of the truck.
If you drive the Dart like I would (like a bat out of hell) the car would most likely overheat from fast acceleration, and more strain on the engine than what is needed. If you drive legaly, it could very well be the thermostat. Be sure that you use the correctly dilluted antifreeze.
bad water pump or thermostat. check both.
because the water pump is not working properly....
Occasional overheating, if not related to low fluid or other problems, is usually caused by a sticking thermostat.
If you are unsure if it is heating because of a water pump or a thermstat, you can find out by removing the thermostat. If it still heats without a thermostat, then you know it is the water pump. Without a thermostat, the water flow has nothing to cause it to heat unless the water pump fails to circulate the water. No circulation of the water would cause the over heating.
You need a new thermostat inside the electric hot water tank, as it is faulty. There is also a reset button on the thermostat that you could try. Does it heat up until the water boils?
The radiator fan is not working,or not working properly,or possibly the thermostat is bad.But,usually if the thermostat is bad the engine would still overheat even if you speed up,so I would suggest testing the radiator cooling fans.
maybe low on fluid? or maybe bad thermostat? or maybe bad water pump?
Water pump not pumping or a pluged radiater