CK20 Running hot

[oldpilgrim]

If you see those temps, you don't have a mechanical problem, you've got a gauge or sending unit issue.

Those temps are showing you're not overheating at all.

 

[SwedeSpeed]

What do you reckon I should do? Replace the gauge, the sending unit or both or just run it the way it is?

 

[gilbertmsg]

I have a 07 and my gauge runs very close to what you are stating. I have no issues with mowing for extended periods at those temps. I have about 800 hrs on my tractor and have learned not to worry.

Eddie

 

[ritcheyvs]

If the indicator doesn't go into the red, I'm not sure you have a problem. The service manual has a table that shows the sensor resistance vs temperature:

60C 153 ohms
80C 74 ohms
90C 55 ohms
110C 30 ohms
120C 24 ohms

If you want to pursue this, you could measure the sensor resistance vs the temp you measure with the IR thermometer.

 

[oldpilgrim]

If you decide you need to fix it, I'd replace the sending unit first. It'll be the easiest piece to replace.

 

[ksbrdmkr]

If the temp stabilizes and you are not boiling water the engine should be ok. If overheating you could probably smell the antifreeze. When mowing with grass seed I stop and clean when the temp is a bit more than half way towards the red and still creeping up. I might worry more about winter operations with not heating up enough.

 

[SwedeSpeed]

Thanks, everybody for your help. I guess I will replace the coolant and the thermostat (probably needs to be done anyway) and go from there. I appreciate all your responses, hopefully I'll learn enough about this machine to be able to return the favor someday.

 

[TJP89]

I don't think you have a problem. You're running a big piece of equipment that is a size bigger than the proper one in the middle of summer. 60" rotary cutter is fine for the CK20, but you're pushing it. I'd expect the tractor to run hot with that kind of load on it. That temp reading is not overheating at all, just running a little hotter than normal, which is to be expected. Keep an eye on it, and if it starts heading up, take action, but if it's stable, it's probably fine.

 

[Coyote machine]

Antifreeze/coolant breaks down over time which is why it needs to be changed periodically. You are running a big hog for that tractor and by replacing/flushing out your cooling system you may find the gauge reads differently. Either way, change out the coolant and flush the system with clean water then refill it with the correct mix of coolant. Keep the radiator and other pre screens and trans cooler fins clean and free of chaff.
Higher RPMs on the engine allow the tractor to run more efficiently and less likely to overheat. Seems counterintuitive, but diesels run cold to begin with and stay within operating temps by running at minimum 1900- 2200 RPMs for a general range. A hog takes a lot of torque/ energy to run effectively, the faster the blades turn the better cutting one gets with less effort. Centripetal force, (of circular motion) keeps the blades cutting effectively and puts less strain on the engine with higher RPMs turning HP power into motion at the blade tips. They don't even have to be sharp necessarily, just spinning enough to beat the grass into submission.

 

[SwedeSpeed]

Just to be clear, I'm running a 60" finish mower, not a brush hog (Bush Hog is the brand name of the mower). According to the owners manual this should not be too big for the tractor. Thanks for the explanation regarding the pto speed. I was thinking higher rpms= more heat, your explanation clears that up.