TN75DA Running Cold HELP!!!

[musselmark]

If there is any water moving through radiator, having cardboard in front will reduce amount of air moving through radiator so cooling is reduced. Sounds like engine is not even warming block up much, or not much water flow through heater when idling.

I understand that but the thermostats job is to keep that cold antifreeze in the radiator and out of the block until the blocks antifreeze gets above the thermostats open temp. this keeps the block from overheating, letting cold antifreeze from radiotor into the mix as needed. the cold radiator fluid is not constantly running through the block . I would assume the heater core is plumbed in with the block and antifreeze is constantly flowing between the two meaning the core and the block should always be at the temperature the thermostat is rated. The other variable is the water pump, at idle perhaps it is not flowing enough and the heater core's fan is cooling it off faster than the rate it can be kept hot so increasing engine speed increases the flow rate to heater core. This is all off topic of OP as he has no heat at all but I am trying to properly understand the way this works.

 

[JerryK]

The fan and radiator on most tractors are over built to keep the thing cool on the hottest of summer days while you are working the bejesus out of it... The fan is sucking in such a huge volume of air that you could probably block the thermostat [ probably, but don't do it ] and the thing still would not heat up much. Working a tractor means different things to different folks, but you have to work the motor to make heat, that means using some HP not just running around. I had to block my 2555 down with a plastic sign board to just a 7-1/4" hole centered on the fan, the board being right in front of the radiator. Now she heats up, but does not heat up too much even when working a big front blower. You can also install a ' winter front ', a covering over the grille on the front of the hood. But you have to block the air some.

 

[Egon]

I understand now how blocking the radiator stops the air being pulled through from the fan. The engine is not warming up the block much. Water is running through all of the lines I have traced. I can feel the temp of the lines running into cab, they are warmer than the top hose, as they should be, but no where near warm enough.

Your on the way now. Just add more rad covering till there is heat. Monitor it so it doesn't overheat.

 

[tcreeley]

I am wondering if the heater core is plumbed on the inlet line to the motor and so never gets heated fluid that hasn't been cooled by the radiator. I think it would be plumbed on the outlet end of fluid coming from the motor on its way to the radiator. The other thought I had, is the thermostat stuck open? I've had this happen before. Being always open, it would never allow the engine to reach operating temperature.

 

[farmer2009]

I know you said you changed thermostats. But have you pulled the new one back off to double check it. Make sure something hasn't gotten lodged in it holding it open. Also test it to make sure it opens and closes when it should. You'll need a stove, pan of water and a meat thermometer. Along with some time. Being a diesel you want a 160-180 degree thermostat.

 

[Jerry/MT]

Hello Everybody, I could not find the new member introduction area, but thanks ADMIN for adding me! I bought a used TN75DA tractor at the end of last summer. It came from Ohio and appeared to suffer some pretty serious salt damage. The AC condenser has literally been eaten away. I can tolerate heat much better than cold, so I was unconcerned about not having air conditioning. I did however think I would still have heat this winter. I do not! I started searching around and found out that I should not be even using my tractor if the TEMP gauge is in the blue area, and not the green. Most information I found pointed to the thermostat, so I changed it. Started tractor up yesterday, it was about 32 degrees outside. I let it run 10 minutes at idle RPM then raised it to 1100 RPM for another 25 minutes, and the gauge still never made it out of the blue. I really need the tractor to work this winter! Any suggestions??
Thanks in advance!

What is the ambient temperature an what are you doing with the tractor to work it?

Unlike a spark ignition engine, a compression ignition engine runs with a wide range of peak gas temperatures in the cylinder. It takes a long time to warm the engine at idle because the peak gas temperature is at a minimum. While you should never put the engine to max power when it is cold, you warm it up by using it at part power. The colder the temperature the longer the warm up. For winter feeding at 10F, our New Holland is in the green band at just about the time I'm finished feeding. The warm up time is dependent on the ambient temperature and the power being delivered. You can get a higher temperature thermostat and might help but you'll still have to use part power operation to warm it up in cold weather.