790 JOHNDEERE

[mowin]

I'm not too far from ya, and It was cold yesterday. Wouldnt be suprised if the tractor never got warm enough for t-stat to open...

[RoyJackson]

My 770 does the same thing. I replaced the thermostat, coolant, temp sensor and hoses. Still, it only creeps up to about 1/4 of the way when working in the summer.

My 790 was the same...as was my old deere 670 and my current Deere 4400. All ran cool (about 1/4 in the green) even when mowing, brushcutting or chipping at PTO RPM

[crashz]

I should mention that I replaced that stuff to eliminate the added heater from the previous owner and for PM. It is an early model (1989) 770, and I wanted to make sure the cooling system was well maintained.

The previous owner installed a heater into a homemade cab (Extremely Thrifty) and temps would never even register on the gauge. The heater, which was fed from the tapped radiator hoses, was about 1/2 the size of the radiator and would barely get warm to the touch. I felt that this was bad to run the tractor so cold ( would consistently smoke at idle) so I removed the heater and everything else besides the canopy. Once the cooling system was returned to stock with new parts, the tractor began running better and quit smoking.

[DEEMEESE]

Thanks guys

[Hooked_on_HP]

The hot water from the engine returns to the radiator through the top hose, passes through the radiator and is pumped back through the engine through the lower hose. So if your cooling system is working correctly the lower hose should be a lot cooler than the upper.
Bill