diesel motor operating temp....

Asked awhile ago about my tractor not getting to operating temp IAW the book (195 degrees)... Only way toget any heat out of it was cover the radiator. Still had to run it a couple hours at almost wide open to get maybe 140 out of it... Always busy, so never really took anything apart, just figured the thermostat was stuck open or missing.... Shop manual shows it has a tstat that isn't available anymore, either has to be special made or there has to be an upgrade for a bunch of bucks to just swap out a 5 buck thermostat. Fooling around on ebay 2 days ago and found an old style thermostat that was getting ready to run out. Bought it, paid, and it's on the way. Had a little time today and unbolted the hood to look if I need to replace hoses while I change the stat. Tractor had already been upgraded to the new type. At that time, I had been running it almost 2 hours and barely had 130 degrees. Upper hose was nice and warm (not hot) and the bottom hose was cold (tstat not opened yet)...
Took the stat out, put it in a kettle of water and it didn't open til 190 degrees.
Is it normal that a diesel runs so much cooler?? Or is it just that with almost double the HP of my last one, I'm just not giving it enough work to heat up? Last one didn't have a thermostat in it and warmed up much faster and the water would almost burn you after a couple hours of running.

Done now

Dave

When you get it working in the summer heat you'll be gld it was running cool in the late winter.

I would check to see if the water pump is working properly and radiator is not partially plugged. Seem it should get hot enough to get heat before running it that long.

(quoted from post at 16:14:14 03/05/12) When you get it working in the summer heat you'll be gld it was running cool in the late winter.

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So, nothing to worry about then????

Sh!t.... Now I gotta find another problem :shock:

Thanks...

(quoted from post at 16:24:08 03/05/12) I would check to see if the water pump is working properly and radiator is not partially plugged. Seem it should get hot enough to get heat before running it that long.

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Wouldn't that stuff make it overheat rather than run cool??

Dave2 Yes what I wrote would seem to make it over heat. But I've seen engines that were really running hot but not putting any heat out of the heater because of low fluid or not circulating properly to the heater.

(quoted from post at 16:38:07 03/05/12) Dave2 Yes what I wrote would seem to make it over heat. But I've seen engines that were really running hot but not putting any heat out of the heater because of low fluid or not circulating properly to the heater.

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Sorry... Maybe I explained it wrong. Motor just isn't getting hot, I was talking about the upper and lower radiator hoses. Don't have a heater.......

if you can't get heat with the radiator covered you aren't
covering it right or enough. Are you covering the outside sheet
metal? because that still leaves plenty of space to let air in. You
have to block almost all air flow thru the radiator like shutters or
curtains did with the old all fuel tractors then when temp is up
you adjust air flow to keep the desired temp.

work her harder.

Tiss the nature of a lightly loaded diesel. All that air drawn
through the combustion chamber but not used in combustion .
Just sweeps heat out the stack Same problem with boilers,
stoves and jet engines when operated with excess air and/or
light load

Our little JD 4600 (37 pto hp Yanmar) is cold
blooded too, put a probe on it and I think it was up
to 160F. I did some research and that's the way they
are. It always warms right up to that point on the
gauge, and it doesn't matter how hard you work it,
never goes any higher. I have a big blanket on the
whole hood all this winter!

For some weird reason International puts too large a
bypass around the thermostat in many tractors. In a
modestly loaded diesel that means that it never gets
up to operating temp or opening the thermostat. If
it is apart, see if you can see the port that
bypasses the stat. If it is bigger than 6mm dia. it
might never heat in the winter. (if it were mine I
would restrict it to 6mm max. Autos have a tiny hole
to allow trapped air to escape, but no bypass).
Jim

I would restrict the bypass more than that..say, 3 MM at the largest..
It only needs to be large enough to bypass enough heated coolant to keep coolant moving in a loop through the block, for more even temperature throughout the block..
If the bypass dumps into the water pump, that is what it will do...
You Want the coolant to cause the thermostat to open, even at idle in the Winter..
It should have capacity enough to cool the engine in the Summer..

Ron..

Some times the gauge will lie! Might check that.