John Deere 4520 CUT thermostat

[shock]

Does anyone know the standard thermostat rating (temp) for a 2009 4520? The technical manual shows 8 different thermostats and ratings from 160F to 210F.

My machine runs about 3/4 on the gauge. Not in the red, but about 1/4" below red, and a 1/4 " above the halfway reading. I want to get a temp gun and read the engine heat, but would like to know what the normal temp should be.

I've changed the antifreeze, it didn't make a difference.

Tractor purchased used 2 years ago and has always read the higher temp on the gauge.

Thoughts?

 

[TractorTech]

The parts manual only shows the RE526915 thermostat. Is your radiator clean from grass and weed chaff? Fan belt tight?

 

[shock]

Do you know the temp rating on that thermostat?

Yes, belt is tight, radiator is clean from debris.

The fan itself has a few chunks off some of the blades, someone must've dropped a wrench or something in there while it was running. That's the only other thing I think might be causing it to run hotter than it should. It's a plastic fan.

I've read the sensor might be off, or the gauge, or maybe air in the system? Or, the thermostat itself..

 

[arlen4720]

3/4 over is where they all run.

 

[shock]

3/4 over is where they all run.

Seriously? Is that a gauge issue? What is the actual temp of the antifreeze at that gauge reading? Do they put higher rated thermostats in them? Please elaborate.

 

[arlen4720]

Seriously? Is that a gauge issue? What is the actual temp of the antifreeze at that gauge reading? Do they put higher rated thermostats in them? Please elaborate.

I can’t recall exactly what temp they run at. I believe it is in the 180-190ish range. I don’t really think it is a gauge “issue”. They just all run 3/4 of the way over. That is normal. I’m attaching an excerpt from the service manual. It is a list of registers for the 3 on board computers. There is a register for coolant temp on both the ECU and ICC.
You enter diagnostic mode 1 and you can view any value in real time from your display. You can determine what your coolant temp is running at, as well as the gauge signal level in percent.
Have fun.

 

[shock]

Thank you so much for the attachment and information!

This will be a big help to me!

 

[Brown Dog]

I had a 4720 open station I ran at max rpm mowing grass for 3-6hrs & it ran hot weekly until I completely removed the thermostat.

I tried everything & couldn’t keep it cool.

 

[arlen4720]

I had a 4720 open station I ran at max rpm mowing grass for 3-6hrs & it ran hot weekly until I completely removed the thermostat.

I tried everything & couldn’t keep it cool.

Did the needle go into the red, or was it 3/4 of the way into the green?

 

[Brown Dog]

Did the needle go into the red, or was it 3/4 of the way into the green?

After several hours of use : the needle would ease over into the Red on gauge & it give an alarm warning in dash.

cleaning radiator screen out didn’t help it. It happened weekly numerous times getting me also hot under the collar lol

after t/stat removal : it never ran hot again.

mine was the Hydrostatic trans ran in B range.

FINE Machine, but I sold it moving up to a 5115M 48spd trans O/S for farm work & Two 31hp 4cyl Turbo Zero 72 inch cut mowers.