Kioti DK55 Overheating

[SmallAcres65]

I have a 2012 Kioti DK55 cab that I mainly cut and roll hay with on my 25 acres of flat land. After about 20 minutes into rolling hay with my 4x5 Vemeer baler the tractor motor becomes over heated. This only happens if I am using the air conditioning. I end up using the tractor with doors wide open and air conditioner turned off. This has been going on since we bought it new. i have had it serviced and found nothing wrong. Is more hp needed? Has anyone else had this problem? I have been looking at a Kioti RX7320 to purchase but dealer cant give me a definite answer if 73 hp would be enough either. Would like other opinions before I purchase.

 

[marchanna]

What all was checked when it was serviced? Did they give you an inspection report?

Have you encountered the overheating any other time?

Are you getting a lot of chaff collecting on the radiator while you're in the field?

 

[SmallAcres65]

did not get an inspection report. Hasn't got hot doing anything else. No on the chaff. I always clean the screens, radiator and air filter each time i bale.

 

[marchanna]

I would recommend starting with the thermostat because it's a common failure and cheap to fix.

If you have a small leak somewhere you may have an airlock causing it to not be able to circulate coolant. For this you can do a pressure test.

That's basically a starting place.

 

[Turbys_1700]

If everything checks out OK on the tractor evidently the round baler in conjunction with the AC on is too much load on the tractor. It appears your tractor HP is on the edge of adequate power for pulling the baler. The AC puts it over the top. I would assume that a 7320 would handle the baler OK. What is the difference in PTO HP between the tractors?

 

[marchanna]

According to the specs, the tractor is 55hp and the PTO is 45.2hp. All I know is that the PTO is independent, not whether it is hydraulic or mechanical. An RX7320 is 73/63hp.

If it is hydraulic, you may be able to solve the problem by upgrading the oil cooler, because oil temperature can get out of control imparting heat on the engine and additional load on the hydraulics, thereby generating a "negative feedback loop". I also agree that the A/C can be the tipper. It imparts additional load and heat on the engine.

More hp will likely solve the problem, but it's a pretty expensive solution.

 

[marchanna]

Quick question: Do you have your remote hydraulic lever in the off/neutral position? This assumes that you don't need the hydraulics to run your bailer.

 

[Looking4new]

You might try turning the A/C off and running just the fan to circulate air in the cab and run the baler that way.
I know it is a 'work around' and not what you want to hear, but it is cheaper than changing parts or seizing a motor due to heat.

 

[marchanna]

Another thought . . .

Does this tractor have a mechanically driven radiator fan or an electric? This may seem counterintuitive, but if it's mechanical, running your engine at a higher rpm may give it better cooling capacity because the fan and water pump will spin faster. I see that the DK55 has an independent PTO 540/1000 RPM, and so you may be inclined to operate the tractor in a higher range to keep the RPM down.

In theory, a higher rpm does not necessarily mean a higher temperature, because it is the amount of fuel injected the equates to the amount of power and heat produced. Before everyone jumps all over this, I know there are other variables in play here, but the OP has made no comments about other performance issues, and therefore it appears that the tractor is producing sufficient hp to perform the tasks, and thus cooling capacity is the issue. Low fan speed and circulation speed certainly can cause overheating.

This would certainly be an easy experiment to conduct.

 

[Bavarian]

55 hp seem quite low to run a baler, at least I wouldn't do it. And asking for air conditioning may put it over the edge.

Keep the RPM up and lower the ground speed.

Coming out of California on I-15 towards Arizona, there are signs saying: "steep incline, avoid overheating your vehicle, shut down A/C."

Switching to a bigger tractor for sure helps.