What causes the engine to over heat?

Question

I have a 97 Dodge Ram Van 2500, what causes the engine to over heat in the hot temp>80F? and on cool days everything is fine. I have checked and changed the radiator fluid and oil, but it still doesn't help. Any thoughts? Thanks

Answer 1

This should be very easy to pin point. With the motor off and cold, remove the radiator cap. Start the motor and let idle until you have the thermostat open, the upper hose will get warm, this will eliminate a bad t-stat. if it dosn't replace the t-stat. withy flow through the radiator, it should be hotter on the top and cooler on the bottom. You will have to have your hands feel the core for temp. If it dos'nt over heat on cool days
I would suspect that your radiator is plugged by about 50%.
I hope that this leads you in the right direction good luck

Answer 2

Five things that can cause a motor to over heat. 1)bad thermostat 2)bad cooling pump 3)leak in the radiator system 4)a plug cooling system in the motor and radiator 5)broken belt. If you are repairing it our self I would look at these areas. If not take the van the a shop that work on cooling system to have check out.

Answer 3

Start with something simple: the thermostat. Thermostat opens or closes the coolant passage as the car heats up. If that's is stuck (or open at wrong temperature) then you'll have cooling problem

Also, you mention that all is well in cooler weather. Check to see if your fan ever turn on. If you let the car idle for about 5 to 10 minutes (from cold - and less if already hot) the fan should should turn on and off. If not then check the fan, fuse, water temperature sensor, electrical wiring / connection.

Answer 4

Check the radiator or thermostat working conditions..or check whether the coolant is properly supplied to the engine, i guess there may be a blockage in the coolant passage which is why the engine is not getting sufficient amout of coolant and gets heated up...

Answer 5

I hate to give credit to a person who calls himself "Mr. Know it all," but I do think he's right. He probably also knows that if you turn your heat on in the summer, it will help cool a hot engine. Heat on full, fan on high, driver and passengers sweating, but engine safer from damage. The heater core, can act as an auxiliary radiator.

Answer 6

too much coolant, too little coolant, maybe your radiator cap is bad. try gettin a cap that has a lil more psi. it will raise the boiling point for the coolant... make sure that the radiator doesnt have a bunch of dirt in the fins blocking the airflow. try to clean it out with a hose squirtin water from under the hood side, to the front of the van...

Answer 7

here is some stuff you can check!. check the thermostat,check to see if the fan works,check the radiator,after you run it a while,check the radiator next to the fan and see if theres cold spots on the radiator,if there is,then its stopped up,give your cooling system a good flushing.

Answer 8

I don't think its your pump because it would overheat all the time, it has to be your thermostat which must be sticking. They are pretty cheap and it will fix the problem.

P.S. Buy one of those manuals (Haynes) at the auto store for your van, it will have a troubleshooting guide and "how to" sections......its very helpful and saves you alot on labor.

Answer 9

If it overheats in stop and go traffic rather than highway driving, read this to understand how your radiator electric cooling fan works:

http://autorepair.about.com/cs/troubleshooting/l/aa032903g.htm

Answer 10

Check the thermostat.