B2920 Overheating while mowing

[troverman]

Maybe I'm just asking too much from my tractor. I have a 2013 B2920 with 400 hours on it. All service up to date. I use it to mow a 20 acre field with grass reaching about 24-28 inches max. I'm using a 48" flail mower to mow the grass. I operate in the lowest range and my tractor is hydrostatic.

Unfortunately, it has been overheating lately. I mowed last weekend, overcast day with temps hitting 60F. It never "overheated" but the gauge approached the red zone. RPMS are steady at the top of the 540PTO rating range.

I checked - no grass covering the grille which has happened in the past. I tried mowing with the front loader at different heights - perhaps blocking some airflow? Didn't seem to matter.

If I stopped mowing for a few minutes, the temp would start to come down.

How can I solve this problem?

 

[85Hokie]

Clean your radiator - reallllly gooood! Looks can be deceiving

Check the pulley on the fan - loose fan ???

Check coolant level.

Check oil level - low oil will make engine run hotter too.

Get infrared thermometer - check temp at radiator - see if gauge is "off" at all

report back your findings

 

[troverman]

I had this problem last year mowing, too. I usually get a ton of grass and wheat chaff that eventually covers the entire front grille. No problem, I get off every hour or so, brush the grille off, and continue on. The temps normally drop. Sometimes, the metal screen in front of the radiator is plugged too. So, I pull it out and clean that.

The radiator seemed clean, but last year I washed it with a hose and quite a bit of crud came out. I'll try cleaning the radiator again. Fan belt is nice and snug, coolant level is good, and I just changed the oil and filled to the correct level.

 

[Bulldog]

Have you changed the antifreeze?

It looses it's ability to dissipate heat and can cause it to run hotter than normal.

Don't want a war, if you change the engine oil to Amsoil it will lower your temps also. I notice my L3000 would run hotter than normal when it was new. After I changed to Amsoil I never had a problem again.

 

[troverman]

Last year I pulled the thermostat to make sure it wasn't sticking. The tractor got new antifreeze then. Antifreeze itself doesn't help cool, it just prevents the water from freezing in the cooling system during the cold season. In fact, straight water cools better than a 50-50 mix of antifreeze / water.

 

[85Hokie]

In fact, straight water cools better than a 50-50 mix of antifreeze / water.

this is very true!!!!

What have ya checked on the list?

 

[BAP]

Have you pulled the screen between the battery and the radiator? My bet is it has a lot of chaff on it and probably some between it and the radiator. I have yet to have my B2920 get more than a little warm no matter how hard I work it.

 

[OldeEnglish]

It probably wouldn't hurt to take the radiator out and give it a nice dunky dunky in some simple green or another good degreaser to make sure it's nice and clean. Beyond that it's got to be thermostat or something is up with the water pump.

 

[Kingcreek]

I'll bet about 95% of the time its a dirty screen and/or radiator.

 

[lugbolt]

95% of the time, the radiator core is dirty. The outside. Lot of times you can't see it until you pull some stuff out of the way, like the screen. The screen catches the big stuff but the little stuff-and dust-gets between the fins and restricts airflow.

Also, check the fan belt. If it slips, the water pump slows down as does the fan-complicating the issue.

Removing the thermostat is not a good idea. The engine needs to get up to operating temperature (170-200 degrees) quick, and running without a t-stat is counterproductive-and actually aids in accelerated engine wear. Be careful with that. Removing it is a crutch. Most Kubota t-stats are fail-safe design anyway, meaning if they "stick" they stick "open" and not closed.

Antifreeze does more than keep things from freezing. It also is an anti-boil (to a point), and probably just as important, it's a lubricant for the water pump seal. It also provides some corrosion protection.

 

[Steve Neul]

Maybe I'm just asking too much from my tractor. I have a 2013 B2920 with 400 hours on it. All service up to date. I use it to mow a 20 acre field with grass reaching about 24-28 inches max. I'm using a 48" flail mower to mow the grass. I operate in the lowest range and my tractor is hydrostatic.

Unfortunately, it has been overheating lately. I mowed last weekend, overcast day with temps hitting 60F. It never "overheated" but the gauge approached the red zone. RPMS are steady at the top of the 540PTO rating range.

I checked - no grass covering the grille which has happened in the past. I tried mowing with the front loader at different heights - perhaps blocking some airflow? Didn't seem to matter.

If I stopped mowing for a few minutes, the temp would start to come down.

How can I solve this problem?

When the engine is cold try running the tractor for a couple minutes with the radiator cap off and see if it's circulating coolant. If your model has a thermostat like a car maybe the thermostat is stuck closed.

I think they have changed antifreeze in the last year or so. I'm having more of my vehicles get the radiator crusting up with lime and or rust.

 

[troverman]

Thanks for the replies, everyone. I'm leaning towards the radiator being plugged up with dust / dirt from summer mowing. I'm going to remove the fan shroud, battery, and overflow bottle, and give it a good rinsing with a low-pressure garden hose. If a bunch of dirt and dust comes out, then I guess that will probably be the answer. Pretty much everything else on the list has already been checked.

I pull that screen out in front of the radiator multiple times when I mow; it gets completely plugged.

 

[85Hokie]

I pull that screen out in front of the radiator multiple times when I mow; it gets completely plugged.

IF that screen is getting "completely plugged" ......there a smaller particles that have found their way through that screen and into the radiator itself!

yup - time to wash the ol radiator. I think you will be surprised as to what comes out!

 

[troverman]

I guess I'm just going to have to clean the radiator almost daily...

 

[Bulldog]

Antifreeze itself doesn't help cool,

I went to a Cat school that teaches different.

Why do you think it's necessary to change anti-freeze?
It never looses the ability to keep from freezing. It does loose the ability to dissipate heat.

Went thru this with both my tractors last year. They were running hotter than normal. Looked back in my records and both were due to be serviced. Changed anti-freeze and everything went back to normal.

 

[Russell King]

If you do find that the radiator is clogged you may try putting an A/C filter in front of the screen to keep it cleaner for longer.
Just use cheaper ones and change out frequently


Sent from my iPad using Tapatalk

 

[troverman]

I went to a Cat school that teaches different.

Why do you think it's necessary to change anti-freeze?
It never looses the ability to keep from freezing. It does loose the ability to dissipate heat.

Went thru this with both my tractors last year. They were running hotter than normal. Looked back in my records and both were due to be serviced. Changed anti-freeze and everything went back to normal.

Anti-freeze will indeed dissipate heat...just not as well as plain water. That's why I said "antifreeze itself doesn't help cool" meaning in relation to the mix. Antifreeze can help raise the boiling point of water about 50 degrees above water, but in reality it is the pressure in a cooling system that raises the boiling point rather than the glycol. I'm not understating the value of antifreeze - obviously it protects the water from freezing and also has corrosion inhibitors...I'm just saying water is more effective at heat transfer than antifreeze.

 

[troverman]

Guys, here's the follow up. Yesterday before mowing I removed the battery and used a garden hose to force water through the fins. Some crud came out. I had done this before, but without removing the battery or fan shroud. By removing the battery, I was able to get more crud out from the lower area. Nothing was *visibly* blocking the fins, but dirt and dust came out.

Then I went and mowed for about 4.5 hours, cutting down on average 2-foot tall field grass in hilly terrain. I used mostly range 2 instead of the usual range 1. The temp was about 80F. The tractor never overheated. Normal idle produced the expected temp reading of about 1/3 up the gauge. Under the heavy mowing conditions the temp was slightly above 1/2. I'm very satisfied with that.

Thanks for all the suggestions.

 

[BAP]

That's good to hear. Glad it was a fairly simple fix.

 

[85Hokie]

Guys, here's the follow up. Yesterday before mowing I removed the battery and used a garden hose to force water through the fins. Some crud came out. I had done this before, but without removing the battery or fan shroud. By removing the battery, I was able to get more crud out from the lower area. Nothing was *visibly* blocking the fins, but dirt and dust came out.

Then I went and mowed for about 4.5 hours, cutting down on average 2-foot tall field grass in hilly terrain. I used mostly range 2 instead of the usual range 1. The temp was about 80F. The tractor never overheated. Normal idle produced the expected temp reading of about 1/3 up the gauge. Under the heavy mowing conditions the temp was slightly above 1/2. I'm very satisfied with that.

Thanks for all the suggestions.

Glad to hear!!!! Once that gauge starts to climb - you'll know it's time for a bath again!!!