CK20 Running hot

SwedeSpeed · Jun 16, 2015

I recently purchased a used (obviously) 2006 CK20 with 330 hours on it. I bought it to do a variety of jobs, mowing being the most common. To do the mowing I got a 60" Bush Hog finish mower. The trouble I'm having is that after about twenty to thirty minutes of work (mowing fields, 6"-8" grass) the tractor starts to run pretty hot. The gauge gets up to about 1/3 between the middle and the red and stays there. I have checked the coolant and oil levels, they are both fine. The coolant doesn't appear to have any oil in it and the oil appears normal. There are no obvious leaks. I removed and cleaned the radiator screen, removed the battery and cleaned out behind it and cleaned the radiator fins (they weren't that dirty, but, I did it anyway). The tractor continues to run hot. The other day I was using the FEL to scoop out some multi-flora rose bushes and I had the same problem, approx. 20 minutes working, gauge rises about 1/3 of the way between midpoint and the red and stayed there. Any idea what the trouble might be? Thanks in advance for any advice you might have, I appreciate it.

Billrog · Jun 16, 2015

Thermostat maybe, run it at higher rpm, clean the air filter or you may have to flush the system if it's had high calcium water added to it ??

SwedeSpeed · Jun 16, 2015

Forgot to mention that I replaced the air filter. I'm not sure if if it's had high calcium water added to it or not. I ordered a thermostat today and am planning to put that in and change the coolant. Is there a coolant drain in the block somewhere? Also, why would running it at higher RPM help? Just because the fan would run faster? Not saying it wouldn't help, just trying to understand. My knowledge of tractors and diesel engines is very limited.

ritcheyvs · Jun 17, 2015

Cross check the head/coolant temp with another thermometer, maybe a non-contact type. Maybe the indication is bad. Is your fan belt tight? Are the radiator hoses pressurized after the engine cools or are there bubbles in the overflow tank (both bad: possible head/gasket leak). Is the radiator hot at the top hose and cooler (but not cold) at the bottom hose (another use for the thermometer)?

Ranchofla · Jun 17, 2015

Swede, welcome to the forum...

My CK20 runs at the middle point of the temp gauge this time of year when mowing ( I live in north florida). I have had it run higher (more in the range you are talking about) but after cleaning the screen in front of the radiator it dropped down to about the middle. In the fall and spring it runs a bit lower than middle but not by much.

Rancho

mj007 · Jun 17, 2015

Ranchofla said:
Swede, welcome to the forum...

My CK20 runs at the middle point of the temp gauge this time of year when mowing ( I live in north florida). I have had it run higher (more in the range you are talking about) but after cleaning the screen in front of the radiator it dropped down to about the middle. In the fall and spring it runs a bit lower than middle but not by much.

Rancho

Ditto - exactly how mine runs

SwedeSpeed · Jun 17, 2015

ritcheyvs said:
Cross check the head/coolant temp with another thermometer, maybe a non-contact type. Maybe the indication is bad. Is your fan belt tight? Are the radiator hoses pressurized after the engine cools or are there bubbles in the overflow tank (both bad: possible head/gasket leak). Is the radiator hot at the top hose and cooler (but not cold) at the bottom hose (another use for the thermometer)?

Fan belt seems tight. I will check to see if the hoses stay pressurized, check for bubbles in the tank and check the temps. I'll post what I find this evening. Thanks.

SwedeSpeed · Jun 17, 2015

Thanks, Ranchofla. I tried cleaning the screen and the radiator fins, hasn't made any difference.

SwedeSpeed · Jun 17, 2015

I got the tractor out, did some mowing and got the same results as usual. It gets a little hot and then seems to stabilize at about 1/3 between midpoint and the red. I used a Snap On infrared laser doohickey to measure temps at the thermostat and the block. Readings were between 196 and 206. The higher numbers were on the canister side. Upper radiator hose is not pressurized after cool down and there are no apparent bubbles in the overflow tank (although it did look like there were some fine particles of dust in there, maybe they fell in when I took the cap off? I dunno.)