tractor with no thermostat?!

[RickB]

The OP is relying on one gauge/sending unit to determine the extent of the overheat in the absence of any numerical values on the gauge or boiling/discharge. What about a sending unit that is out of range resistance-wise? How about verifying coolant temp with a known instrument of the OP's choice to determine if, in fact the engine is "overheating" ? Me thinks it is not.

 

[Old Virginia Joe]

The OP is relying on one gauge/sending unit to determine the extent of the overheat in the absence of any numerical values on the gauge or boiling/discharge. What about a sending unit that is out of range resistance-wise? How about verifying coolant temp with a known instrument of the OP's choice to determine if, in fact the engine is "overheating" ? Me thinks it is not.

Sure that's possible, but it sure "seems" hot when I cut it off (to my novice perception). Put my head down near the engine in the silence and listen to it silently hum inside with what seems to me to be excess heat, not to mention the heat radiating off it. Also, it wants to run on for 6-8 seconds after I kill the key, knocking along, before it goes silent. Does not do that when it is not "hot." Reasons I don't see a way to determine that coolant temp to disprove the gauge are: 1. I cannot remove the cap with it scalding hot to stick a thermometer in the rad cap. 2. There seems to be no coolant system drain installed on this tractor to drain off some coolant safely and temp test it. (Is there supposed to be a petcock drain somewhere on the early F-4000? If not, is there any aftermarket one that is compatible with this model, or inline hose fitting drain that does not require tapping the radiator metal?) Is a temp infrared gun adequate to read the iron surface temp? I know someone suggested that, but I was skeptical if that would really mean anything. Is the sending unit seperate from the guage? i can certainly R&R that easily if u think I should at this point.

 

[RickB]

I use an IR gun with great success. It would be my tool of choice if I were in your shoes. I have read absolutely nothing here that makes me believe your tractor is actually overheating. Shutting down a tractor at operating temp will often cause the coolant trapped in the cylinder head to boil a little and make some noise. That's why a brief cool down period is appropriate. Any engine at operating temperature will "seem" hot. Heat a pot of water to 160 or so degrees and see how long you can leave a finger in it. Yes, the sender is separate from the gauge. The gauge is in the instrument cluster, the sender is in the front of the cylinder head. I'm not telling you to change it; I'm telling you to be certain your tractor is overheating before doing anything else.

 

[Old Virginia Joe]

I use an IR gun with great success. It would be my tool of choice if I were in your shoes. I have read absolutely nothing here that makes me believe your tractor is actually overheating. Shutting down a tractor at operating temp will often cause the coolant trapped in the cylinder head to boil a little and make some noise. That's why a brief cool down period is appropriate. Any engine at operating temperature will "seem" hot. Heat a pot of water to 160 or so degrees and see how long you can leave a finger in it. Yes, the sender is separate from the gauge. The gauge is in the instrument cluster, the sender is in the front of the cylinder head. I'm not telling you to change it; I'm telling you to be certain your tractor is overheating before doing anything else.

so, you're not concerned about the engine running on after I cut it off? What is causing that---not overheating? (I want to believe you, that I have no problem, but I don't want to blow a head gasket, or ruin the engine . . . . . )

 

[LD1]

This myth is right up there with leaving a battery on a concrete floor will discharge it.

Brian

Fact: Leaving a battery on a concrete floor, the battery WILL discharge overtime.

Fact: Leaving a battery on ANY floor, or even a workbench, it WILL discharge overtime.

Sorry, couldnt help it...

I'm sorry this is taking so long to resolve, so I appreciate you all sticking with me on this til I can get it resolved. I only get to work on mechanics on weekends or a day off. So, the thermostat (160) has been installed now. I can see water flow inside the top of the radiator (with the cap left off). It appears to (as I stand facing the front of the tractor) to be flowing from my left (where the top hose enters radiator) diagonally to the right. Is that the correct flow pattern? The water pump is not leaking. The temp guage was replaced by the PO, and is only 10 months old. I did a little discing this morning, and I was optimistic. Temps looked good. Then I went to try to finish my mowing job in a thickly grown up old field which includes saplings here and there. I am using a JD 509 five foot bushog. After awhile the temp guage reached the red zone and I cut it off. Here we go again. I think I said before the PO said he had the radiator cleaned and flushed, and the manilla tag was still hanging on it from the rad shop until just last week, so I assumed that is OK. As far as the fins maybe being clogged, the fan has an intact shroud, and definitely sucks air thru it, be it leaf particles, or a dangling rag, so I can see it is passing air thru. I see no oil in the water, nor water in the oil. I hope I have addressed all the previous response questions and suggestions.

Is it possible a JD 509 is too big for this tractor? Just asking out of desperation. :confused2:

Bushhogging eh...No a 5' is not too big. If anything, it is a few sizes smaller than I would choose.

Have you tried compressed air and given the radiator a good blow-down. Rid it of all the pollen, seeds, etc. Just because it looks good on the outside, doesnt mean it isnt plugged tight inside. I do ALOT of bushhogging with my kubota. hundreds of acres a year. With a clean radiator, it never gets more than 50% on the gauge. And I am using a 6' cutter on 29 PTO HP, and going as fast as I can, and usually on hot 90 degree days. When the radiator starts to get dirty, it flirts with the red. One time I tried using a garden hose to get it good and washed out. It still flirted with the red on my next job. So got the blow gun out and blew it out thoroughly. Problem solved. But using the hose did appear to clean it well. But obviously there was still lots trapped in between the fins and packed around them. That debris acts like an insulator, so even with a little airflow, little to no cooling happens.

 

[Soundguy]

on the run on. are you bringing it down to idle for a few secondfs before cutting it off?

and have you checked timing.. or advanced it any?

what plugs are you using?

 

[boggen]

Sure that's possible, but it sure "seems" hot when I cut it off (to my novice perception). Put my head down near the engine in the silence and listen to it silently hum inside with what seems to me to be excess heat, not to mention the heat radiating off it. Also, it wants to run on for 6-8 seconds after I kill the key, knocking along, before it goes silent. Does not do that when it is not "hot." Reasons I don't see a way to determine that coolant temp to disprove the gauge are: 1. I cannot remove the cap with it scalding hot to stick a thermometer in the rad cap. 2. There seems to be no coolant system drain installed on this tractor to drain off some coolant safely and temp test it. (Is there supposed to be a petcock drain somewhere on the early F-4000? If not, is there any aftermarket one that is compatible with this model, or inline hose fitting drain that does not require tapping the radiator metal?) Is a temp infrared gun adequate to read the iron surface temp? I know someone suggested that, but I was skeptical if that would really mean anything. Is the sending unit seperate from the guage? i can certainly R&R that easily if u think I should at this point.

all the radiators i have on vehicles to tractors, there is a drain plug directly on the radiator itself.
location, if setting in driving seat, looking at radiator, the drain plugs normally the side of radiator facing you, in the bottom left corner.
though, the drain plugs, have been noted by others, to be at other locations. some place around the bottom edges of the radiator.
i have seen a make shift drain plug, were radiator hose was cut in half. and then a small piece of pipe placed between them, and a centering tapping drain plug drilled and tapped into the pipe.
if all else fells just undo lowest hose on radiator, it is messy this way but what ever gets it done.

 

[skylarkguy]

Not sure if i missed this but has the radiator cap been checked for proper functioning? If the cap doesn't allow proper pressurizing of the system it will run hot.

 

[Old Virginia Joe]

skylarkguy---It came to me with a 7 lb cap, but Soundguy advised me to switch to a 4 lb, so I did, and am using a brand new (from NAPA) 4 lb cap. I have to assume it works. I called Stant and they don't even offer a 4 lb!! Thanks for the idea!

Hoping to get a number off those spark plugs this evening SG!

 

[the old grind]

15lb cap makes your system work like a pressure cooker, raising the boiling point by containment. A 7lb cap won't allow it to get as hot before boiling over. However hot your tractor seems to be, if your coolant was much hotter than what it takes to boil it would blow out the cap. Hot? Yes. 'Too hot'? Perhaps a matter of degrees (no pun intended) and IMO a timing check should be part of of a thorough analysis, even more so if one had gas vs diesel engine, where points' rubbing block wear could allow advance to creep up.

BIG +1 on post #33!! Also, IMO 5 min is hardly too long to cool down with any engine that works. ... Lots of good info here, and everything should be checked/eliminated as possible causes.