New Yanny

[tallyho8]

That's one of the main differences between a gas engine and a diesel. Idling a gasoline engine for an extended period is harmful, fouling spark plugs and causing overheating while a properly maintained diesel can idle forever at a very low temperature. A while back I heard about a man who left his diesel tractor idling all night during a hard freeze and his radiator froze up. They didn't say what type of tractor it was.

 

[normde2001]

That's one of the main differences between a gas engine and a diesel. Idling a gasoline engine for an extended period is harmful, fouling spark plugs and causing overheating while a properly maintained diesel can idle forever at a very low temperature. A while back I heard about a man who left his diesel tractor idling all night during a hard freeze and his radiator froze up. They didn't say what type of tractor it was.

That's why we have antifreeze.

 

[greatrandini]

Not advising a hot shutdown, but I have noticed that leaving the engine running (to avoid a hot shutdown) and pulling the screen often shakes chaff loose which the fan then pulls into the radiator. Point is, after a few screen cleanings done with the engine running, you may need to do a complete shutdown to clean the radiator, also. If so, be sure to do it before the radiator gets so blocked that it won't cool at idle.

I never tried to take the prescreen off with the tractor running! I just idle it down for a bit. Then I shut her down and clean the pre screen. I need my fingers for work. I guess though that if it were overheating I would not want to shut it off and would want to get that screen cleaned off right now.... So I can see myself attempting this.. If my unit were over heating like his I would clean the radiator fins and see if that did it. If it did not work I would pull the radiator and have it boiled out at the radiator shop......

 

[Tom_Veatch]

I never tried to take the prescreen off with the tractor running! I just idle it down for a bit. Then I shut her down and clean the pre screen. I need my fingers for work. I guess though that if it were overheating I would not want to shut it off and would want to get that screen cleaned off right now.... So I can see myself attempting this.. If my unit were over heating like his I would clean the radiator fins and see if that did it. If it did not work I would pull the radiator and have it boiled out at the radiator shop......

I would have used your approach - idle cooldown, shutdown, clear screen, resume operation - except my screen was clogging so thoroughly, so quickly, that I wasn't sure the temp wouldn't keep rising, even at idle. About two circuits and the screen was a solid mass of light fluffy stuff with little or no airflow through the radiator with the temp gauge headed for the redline.

So I opted to clear the screen with the engine running. Since the screen is on the opposite side of the radiator from the fan, I didn't feel my fingers were in any danger. Although dismounting with the engine running is one of those safety no-no's, ensuring the brakes were locked and both transmission and powershift in neutral, I managed it without getting run over. As soon as I pulled the screen, the temp would began to fall back to and below middle of the green arc.

The chaff was so light and fluffy and the suction from the fan was so great, even at idle, that trying to brush the chaff off with the screen in place just wasn't getting the job done. But, as soon as the screen was pulled clear of the radiator, globs of the chaff would fall off, and the fan would pull it into the radiator. So, every three or four screen cleaning resulted in the need for a radiator cleaning.

Two circuits, stop and clear screen, two more circuits, stop and clear screen, cooldown, shutdown, clear radiator, resume mowing, repeat ad nauseam. So went my first time ever to do any bush-hogging. Next time it won't be in head high grass and weeds so maybe it won't be quite as bad. But, if it happens again, I'm sure I can come up with something to keep the radiator clear when I pull the screen.

 

[Tom_Veatch]

...
A while back I heard about a man who left his diesel tractor idling all night during a hard freeze and his radiator froze up. They didn't say what type of tractor it was.

That's why we have antifreeze.

Had that happen to me one morning on my way to work a few years ago. Jeep Cherokee, gasoline engine, record breaking cold snap. The radiator froze up and the engine overheated. Shut it down in an area sheltered from the wind and residual heat melted the ice. Resumed the commute with a piece of cardboard almost completely covering the radiator front.

Had antifreeze in it, but obviously not the right mixture for the conditions.

Even had the carburetor ice up in a '67 Camaro (327 4bbl) a couple of times. I'm sure the pilots in the audience are familiar with carburetor ice but that's the only time I've ever had it happen in an automobile engine.

 

[normde2001]

Tom, it sounds like you might be running on the edge of too hot normally. Where does your needle normally sit on the scale? Mine barely gets to the 1/8th mark, then barely creeps up with about 2" of chaff totally covering the screen. I then shut it down, remove my whisk broom from the toolbox and brush off the screen.

 

[Tom_Veatch]

Tom, it sounds like you might be running on the edge of too hot normally. Where does your needle normally sit on the scale? ....

Most of the time, the needle is at about 1/4 of the green arc. On rare ocassions, I've seen it up to 1/2 green. I've never seen it above 1/2 scale except during that mowing job in the Kansas heat with the screen full of fluff and dragging a 5' JD 305. I don't know what those gauge positions translate to in terms of degrees.

Since the engine has a thermostatically controlled cooling system, it tends to come up to temperature fairly quickly and holds a stable temp over a broad operating range. I know a lot of these tractors don't have thermostats and some don't even have water pumps. I'm assuming mine has a thermostat, but I've not had the upper hose off and seen it. The parts book shows a part at the proper location and the number, 129350-49530, crosses to a part that Hoye calls a "thermostat".

 

[normde2001]

It does appear that you have a thermostat. I'm not familiar with the green zone but it appears that straight up 12 o'clock is about 195, pegged cold is 140 and pegged hot is 255.

 

[greatrandini]

Tom, did u c where Gizmo wrapped the front end of his tractor in screen? It beats the heck out of constantly cleaning the prescreen!

 

[Tom_Veatch]

Tom, did u c where Gizmo wrapped the front end of his tractor in screen? It beats the heck out of constantly cleaning the prescreen!

Yes, I saw that and thought it was ingenious even if the "bra" was a little ugly. A little cutting and fitting to clean it up and, I think, he'll really have something there.