d4 6U operating temp

I believe around 160-170-F, depending on engine load.

-do you think running it a bit hotter would hurt anything Gary? that's luke warm by today's standards...

Depends on how you are going to use the tractor, mine will run on the cool side just grading dirt or stone but heavy dozing or pulling a plow it will run hot on a hot day. I also have a reversible fan on mine, its mostly blowing forward but when pulling a plow or ag work it will run cooler with it blowing back.

Depends on how you are going to use the tractor, mine will run on the cool side just grading dirt or stone but heavy dozing or pulling a plow it will run hot on a hot day. I also have a reversible fan on mine, its mostly blowing forward but when pulling a plow or ag work it will run cooler with it blowing back.

thanks Gary, yes there's a few factors for sure

-i like the 180-190, 200 degrees max...as long as everything is up to snuff..

Boiling is 212 degrees F for water. I think if you use 50% coolant the boiling point is a bit higher, like 223 degrees F. or higher concentrations may be up to 235 degrees F

Since, I think, most cooling systems can use just water for cooling if you really wanted to, the rule would be you want a temperature below 212F. Once you start boiling, you are creating steam, which expands, which would cause pressure to increase in the cooling system. Which extra pressure could mean bad things if the pressure cannot be released in a reasonable manner.

Just don't overheat the engine or the head can crack and other problems can happen.

6U1 to 9063 takes a 6F9467 regulator 166* to 170* operating temperature.
Wide open at 183*F.

[quote="Old Magnet"]6U1 to 9063 takes a 6F9467 regulator 166* to 170* operating temperature.
Wide open at 183*F.[/quote]

this is what my new gauge reflects. Thanks