Hot when mowing - B2400 - Cools off if I stop moving (even with blades going)

[mikebpbx]

I have a B2400 that gets almost-overheated when I mow for about 20 minutes.

If I just stop and sit (no moving but PTO still engaged) it will quickly cool off.

Any ideas what to check? If I use the loader and drive around for 20 minutes, no issues.

If I engage the blades and let the tractor sit, no issues.

If I'm moving with the mower blades it gets as high as the gauge in the pic (just below hot).

Anything else and it's less than half on the gauge.

 

[Trash Panda]

Mowing increases load, which makes more heat in the motor.

Seems like a cooling system refresh is in order, IMO.

 

[Hugo Habicht]

The "throttle" of the engine is controlled to keep constant revs. When you are mowing the engine has to work way harder than when you are stopped, blades just turning requires very little power.

In general check the cooling system, first of all the mesh or filter before the radiator (if any) and the radiator fins themselves if they are clogged up. A lot of Radiator fins bent? Cooling fan drive belt springs to mind. Furthermore deposits in the radiator (coolant with corrosion inhibitors changed regularly?). Coolant level ok?

Picture is how the radiator looked like when I got the tractor.

 

[mikebpbx]

I cleaned the screen and washed out the fins (let it dry before running again, so the dry stuff didn't just stick on)

I'm not sure about the inside but the outside is OK (I have a B2100 too and was aware of this).

The fan spins, seems to be in good shape and has decent tension.

I suppose I'll flush the coolant next...

 

[Russell King]

If it was me…
If you drain the coolant I would probably change the thermostat. For sure I would remove the radiator and clean it well on the outside while off the tractor. That way you can shine light through the fins and look from the other side to see if some areas are still packed full of whatever. You may be able to do that on the tractor but there is NOT enough room or access on mine to be 100% sure it is clean.

The radiator is pretty easy to get off my tractor also, so not really a big deal to remove.

 

[Hugo Habicht]

I cleaned the screen and washed out the fins (let it dry before running again, so the dry stuff didn't just stick on)

I'm not sure about the inside but the outside is OK (I have a B2100 too and was aware of this).

The fan spins, seems to be in good shape and has decent tension.

I suppose I'll flush the coolant next...

Were the radiator fins very dirty?. If yes, that was your problem, I would do another test run.

If the coolant has not been changed for a few years it may not be a mistake to do that. If it comes out rusty coloured this is an indication of corrosion due to inhibitors used up. Depending on coolant you may have to change it every three years. Kubota manual of my tractor says even every year.

Is coolant level good now?

 

[dirtydeed]

if coolant level is good and radiator clean, the first thing I would be looking at is the air filter itself.

Do that first.

 

[Bee-Positive]

Just a thought...check your hydraulic fluid level. It runs both the mid PTO and drive wheels. Not sure if being low would over heat the engine though. Never hurts to check.