Another overheating Thread

[Marshall]

It sounds to me that that fan is not coming on when it should.
I seen a fan blade put on backwards on a old car one time, caused all types of problems, no one noticed till motor pulled.
But I don't think on these that could happen.
When sitting with it hot, have you opened the hood to make sure that the fan is blasting, not just free wheeling, you should hear it blasting. Hit the gas, it should keep up with the motor when hot.

 

[KJHagg]

It sounds to me that that fan is not coming on when it should.
I seen a fan blade put on backwards on a old car one time, caused all types of problems, no one noticed till motor pulled.
But I don't think on these that could happen.
When sitting with it hot, have you opened the hood to make sure that the fan is blasting, not just free wheeling, you should hear it blasting. Hit the gas, it should keep up with the motor when hot.

I'm second guessing everything. All seems to be working right but I'll verify.

 

[Marshall]

Hunterdan has a good point, You could also put a good light at front of motor and look thru the AC condenser & rad to make sure it's not plugged, thou I think you said Rad was new, in that case should be clear, double check the AC is clean and not plugged up with bugs. dirt.
I would change the thermostat again, I have had new ones that where NFG. Also make sure the rad hoses are good, but that should be more of a hi speed problem.
Just sipping coffee and thinking out loud.

 

[Jeepwalker]

I replaced a leaky radiator a month ago (in a car), and the gap between the condenser and radiator was full of years of dead bugs, moth wings, some grass, and debris. More than I normally see. And the gaps between the condenser fins were also quite plugged. Hard to imagine why the vehicle didn't overheat.

Did you (OP) look for bubbles in the radiator cap area... and sniff as it was running to rule out a leaking head gasket? Check the tailpipe for being extra-clean. A newly leaking head gasket (not to the point of blowing steam though) can definitely cause overheating.

Even if the fan clutch was bad, there should be enough wind at highway speed to keep it cool. But not if the radiator/Condenser is plugged, or some other issue is going on.

 

[Jeepwalker]

I've had it where an impeller on a water pump wasnt pressed on tight enough. Or...when the vehicle got hot..the heat caused the impeller to slip, where when it was cool, it would grip enough to flow coolant. So it would overheat on the road, not while idling. That was a tough one to debug!

So, flaky water pump isn't out of the question.

 

[Tony Donato]

Blockage somewhere in system.

+1