I have checked my temp by obd2, it shows me a temperature between 203 and 210 deg far, engine running.

Please tell me if this ts a normal temperature.

 

That's normal.

 

Looks good, that's where mine sits.


210 is right at the mid point, right of your needle in the pic.

 

I have read that some of you have replaced the original 203deg thermo by a 180 deg. Is there any advantage to do that. Isn't it better for the motor to run with a lower temperature?

 

If you have snow 2-3 months out of the year, I'd leave the stock 203f Thermostat in the truck. If you do a bunch of towing or hauling during the summer months, you could probably get away with a 180f thermostat.

There are people who say going to a 180 degree thermostat is pointless unless you have a tune, but those are people who obviously know nothing about Pre-detonation and how that affects an engine. Hemi engines in general are less prone to knock than pretty much any engine on earth because of the spherical design...even with the more complex design of the new heads this still holes true. Pre-detonation is when fuel ignites prior to the timed ignition event of the engines design parameters due to excessive heat. Our engines computer system is equipped with knock sensors to listen for this condition and if it doesn't hear this condition it can retard or advance the timing to the optimal point of ignition for maximum power within the stock design parameters of the ignition system, on the other hand if it hears knocking the computer will pull timing and your performance will suffer. Putting a 180 Degree thermostat would be the mechanical equal to putting in a higher octane fuel to combat pre-detonation, essentially those actions are almost one in the same despite their very different methods.

If your goal is to simply eliminate "knocking" or its more familiar term "Pre-Detonation" under high stress high heat situations like towing or racing then most certainly a 180 degree thermostat will help you no matter what even WITHOUT a tune. It basically gives you a safety cushion against damaging pre-detonation when there is high torque demand from the engine.


WITH a tune, you can get more wild with your engines timing and take advantage of the cooler combustion chamber temps to run the timing at an even more optimal point for making more horsepower.

 

Thanks so much for all the details. My point of view is not to avoid knocking on high torck but have a lower temp running to save the engine himself. If the temp is lower, i guess its better for all accessories... Pump, fan cooler, etc..

I dont want to tune it.
Ed

 

I got always upper hose very hard to press. I have replaced my thermo and cap of radiator. Liquid colling rising normally in plastic reservoir. Actually by cold, its on middle. When engine is hot, its 2 or 3 centimeters higher. Sorry i have not converted in inch. For me its a normal level. I will try again to evacuate air in system. So the cap do his job. Do you think its again air blocked into the system? Radiator is now hot and lower hose seems also hot.

 

Your temp gauge would indicate that everything is fine. As I stated in your other thread, With the 203 degrees F thermostat water by itself would not boil and it would only start to boil in open air at around 212 degrees, in a closed system that boiling point is raised, and with antifreeze it raises the boiling point even further. You would need to overheat at around 240-250 degrees for this to be an issue. So long as the cap you bought is the correct cap for this truck, it should eventually burp itself of any potential air bubbles or air in the system even if you didn't purge it properly, which I'm certain you did do correctly.

Unless you experience an overheating scenario I wouldn't worry about it. If that temp gauge needle goes anymore than a few needle widths over half way, I'd say theres a problem, but if it stays where its at in the pic and even up to the mid point you're totally fine.

 

Ok sir, thanks for your time for properly response. If i have not to be worried about temp, i have to say that the pressure into system, tell me that something goes wrong. Yes i have a properly cap, 16psi for my truck. I am glad to know that if there is a pocket air, the cap will evacuate it through the plastic reservoir, naturally.

I will be carreful of the amount of cooling in my system, and level of motor oil. If there is any changes, means there is a main gasket problem.

I dont understand from where comes these high pressure.
Ed from belgium

 

The Pressure isn't enough to trigger the radiator cap to spray the coolant back into the reservoir so there again I think you're fine.

If the hose was hard because of a head gasket leak that leaks compression into the cooling system, in short order you would be able to watch the reservoir and see if it bubbles up, because I assure you that if you had a bad head gasket it would leak that compression past the 16psi radiator cap and within a minute you would see some sign of that, especially if you put your finger over the reservoir vent and feel pressure, this would also be followed within 20 minutes of driving of spikes of overheating along with it because of it pushing pressure and coolant out as a result.


It could very well be that your radiator hose if it was ever changed, has a spring inside of it that helps it keep its shape and avoid collapse and it really isn't over pressured after all. Have you felt the bottom radiator hose? Usually radiator hoses will get somewhat hard after a drive, so I don't think you have any problems.