340 temp question

[Austinsguns]

71 Duster 340. Is running 3/4 of the way to hot on the temp gauge (stock gauge). After a ride, I pulled the cap off the radiator and it was 205 degrees. Is this too hot? I replace the thermostat (was 190 I put in a 180) and it did not help. I also notice the system never has any pressure, even when hot.


Motor is stock with stock radiator. Coolant levels are good, radiator is clean.


Please let me know your thoughts.

 

[1968FormulaS340]

That sounds about right. When you shut a car off the temp goes up before it starts to go down again (everything is still hot but you have cut off the airflow and circulation).

You could install a good after-market gauge for a bit so you could get an idea of what is really going on compared to your factory unit.

205 isn't hot.

 

[68gtxman]

If the cooling system never has any pressure, then there is a problem with it! First replace the radiator cap, assuming you haven't noticed any leaks and no "milk in the oil".

 

[1968FormulaS340]

Sorry, I didn't see the pressure part. Yes, I agree, replace the cap with a quality unit.

 

[Austinsguns]

No milky oil. I will replace the cap. Is there a certain cap I should be looking for pressure wise?

 

[68gtxman]

Yes, find a 16 psi cap.

 

[Austinsguns]

New cap fixed it, runs midway on temp gauge. Thanks all.