1972 CAT D4D overheating

Your heating problem is being caused by the transmission and torque converter overheating. Check the simplest things first. Are the brakes unlocked? Have you checked the transmission oil level? Let us know what you find.
Craig

Thank you for your quick response.
The oil level is slightly above the max on the dip stick. The oil itself is milky. Like very milky. Most likely from sitting all those years in the field, exposed to the weather.

The brakes are sticky but do work. The pedals don’t return on it’s own at moment. Work in progress but I don’t believe they are locked.

But how could the breaks cause the coolant to overheat? Isn’t it a dry clutch?

Please post your serial number, 1972 D4D has very little meaning.
Bob

The serial number is: 83J1810

Your machine is a early power shift and the brakes are dry. Or at least it came that way.
Does the temp gauge on the torque converter work?
your readings on the transmission oil cooler might be backwards.
If the gauge on the torque works put the transmission in 3rd gear, stand on the brakes and run high throttle and watch the heat gauges.
Bob

[quote="bluox post=254323 userid=2232"]Your machine is a early power shift and the brakes are dry. Or at least it came that way.
Does the temp gauge on the torque converter work?
your readings on the transmission oil cooler might be backwards.
If the gauge on the torque works put the transmission in 3rd gear, stand on the brakes and run high throttle and watch the heat gauges.
Bob
 [/quote]
You are right, my readings for the transmission oil cooler is backwards [img]/media/kunena/emoticons/doh.gif[/img]

I‘m not sure if the transmission oil gauge works, the needle does move a bit but the engine is just way to fast overheating to really test the other instruments.

Is the possible that the impeller of the water pump is loose or worn in a way that it can’t pump enough coolant to cool the engine?

Very milky oil usually indicates the transmission oil cooler has failed or water has entered from another source. If the the tractor was run a long time in this condition you might have serious transmission problems. 
The torque converter uses the engine coolant to keep it's temperature down via the trans. oil cooler. bluox is correct you can test the gauge by standing on the brakes with the tractor in 3rd gear and the engine at full throttle. The gauge should rapidly rise toward the red. 
Craig

[quote="seiscat post=254328 userid=5422"]Very milky oil usually indicates the transmission oil cooler has failed or water has entered from another source. If the the tractor was run a long time in this condition you might have serious transmission problems. 
The torque converter uses the engine coolant to keep it's temperature down via the trans. oil cooler. bluox is correct you can test the gauge by standing on the brakes with the tractor in 3rd gear and the engine at full throttle. The gauge should rapidly rise toward the red. 
Craig[/quote]

Sounds like that I have to replace the transmission fluid rather sooner than later… I will take care of it today.
Could the milky trans fluid cause the coolant to overheat?

I just tried to stand on the brakes in 3rd gear. The gauge doesn’t rise at all. So looks like it’s not working.

This new gauge is available on eBay:
https://www.ebay.com/itm/383670453640