SO I just replaced the radiator, water pump, thermostat...pretty much the entire cooling system. I've been driving around a bit and it will run about 210-218 going 60 mph, and going slow it wants to run 205 with a 195F thermostat in it. Is this normal?

This is what the thermostat looked before it was changed


This is the new stuff

 

Looking at the coolant color and that thermostat you need a complete flush or two.

 

I did that too, that was a picture of the old stat

 

Mine wasn't that dirty and it took flush after flush to get it all out. Just when you think it's clean, the next time you flush it'll be filthy again.

How's the fan clutch?

 

Everything was a clear, even the heater core when I flushed, flushed it 6 months ago also when I got it. The fan clutch is brand new

 

Those numbers are not way off. At 60mph on the open road does it ever settle to a particular number (or close), or does it keep cycling between 210 and 218, like building up, and then falling down, then building back up again.

 

Just cycles, but before changing everything it ran about 190-200 going 60

 

Usually, that cycling of temp at speed is an indication that the thermostat is not operating smooth as it should, and is letting temp build and then opening, then cooling and shutting down a bit, then repeating the cycle.

My old thermostat was doing exactly the same thing. Wasn't hurting anything, but the numbers were getting a little higher over time. Got to where it was cycling between 210-218 (just like yours) at highway speeds. It was even more pronounced after I changed the water pump last summer (bearing was going). So, I finally put a new one in a few months ago, and it now has exactly the numbers and behavior that you did before you changed yours.

Because the tstat is pretty easy, I would probably put another one in and see. Because I didn't want to do the job twice, I did boil some water on the stove at 200f to ensure it was opening properly (and smoothly) before installing it.

Also are you getting the temps from your gauge only? Try pulling it with an IR thermometer at the tstat housing (right by the coolant sensor), or via OBD2 to make sure that the numbers agree. (I monitor mine via obd2 via a homemade digital dash).

 

I never thought that, but I might swap it to a lower degree stat, because it likes to overheat in the Utah summer.

And where would I get one of the IR readers?

 

Infrared Thermometers can be bought at lots of places now. Any auto parts, large hardware, or harbor freight would have them.

Based on your logic, you could get a 32f thermostat and enjoy homemade ice cream right from the valve cover. I would stick to the 195f if I were you. A lower one will -not- keep it from overheating.