Operating Temp Question

[aaluck]

I have a L4400 HST 4WD, 800ish hours. I have noticed lately that my temperature gauge is running high when bush hogging. I have been mowing a 3 acre lot next to me for the lady that purchased it.

It stays in the white top of the white bracketed area just below the red. In other words the needle is in the top white bracket/boundary. I just do not remember it being that high in years past. It only does this when mowing, not post hole digging, fork usage etc.

Conditions are hot 90+ with little to no wind. All fluids are fine, no debris blocking air flow to the radiator. Grass is only about knee high. Blades on BH are 4-5 years old with little usage, since I purchased a bigger/faster zero turn for mowing. No bogging down, etc.

 

[MapleLeafFarmer]

hows the belt condition / tension?

given the hrs and heat might be due for some TLC or replacement.

 

[North Idaho Wolfman]

When was the last time the coolant was changed?
Is the radiator (not the overflow) full of coolant?

 

[85Hokie]

I have a L4400 HST 4WD, 800ish hours. I have noticed lately that my temperature gauge is running high when bush hogging. I have been mowing a 3 acre lot next to me for the lady that purchased it.

It stays in the white top of the white bracketed area just below the red. In other words the needle is in the top white bracket/boundary. I just do not remember it being that high in years past. It only does this when mowing, not post hole digging, fork usage etc.

Conditions are hot 90+ with little to no wind. All fluids are fine, no debris blocking air flow to the radiator. Grass is only about knee high. Blades on BH are 4-5 years old with little usage, since I purchased a bigger/faster zero turn for mowing. No bogging down, etc.

So, lets get down to numbers - there are those that think and engine should run "cool" - what ever that temp is !!!!

Best and ONLY way is to measure the temp at three locations.

First - measure with an infrared thermometer


at the thermostat - should be 180 ish .......... most open at 160 and fully open at 180

then check the top neck of the radiator ........... should be close to 200 or a smidge higher..... 210

THEN check the lower neck of the radiator - it should be 75 degrees (F) lower than top.

if this does not come back in line ..............

do as mentioned - clean the $%#$@@ out of the radiator, not once, not twice , 3 times!!!! air will not do it perfectly . Allow it to be cooled off - then get some radiator cleaner for the outside and spray and hose down and do it again!

AND yes - change the antifreeze coolant. BUT run a solution through the radiator first - I use 50-50 vinegar solution, run it hot and empty. Run 100% distilled water through it ......... drain.

then add the new antifreeze and see if temps come down.

 

[aaluck]

When was the last time the coolant was changed?
Is the radiator (not the overflow) full of coolant?

Yes it is full. I am not sure it has ever been changed. I will do that like @85Hokie stated above and see if that works.

My wife has one of these and I will check the temps as well.

I am gathering from the comments it should not be staying up that high so something is going on.

 

[North Idaho Wolfman]

I am gathering from the comments it should not be staying up that high so something is going on.

No, it doesn't sound normal.
And it could be a false read from a bad temp sender or Gauge
The WSM will tell you how to test.
If you don't have the WSM just ask.

 

[jaxs]

Much good information. May I add my thoughts? Overheating is right up there with the major killers of diesels engines of all colors and sizes. For that reason I upgrade temperature monitoring on all when new. If engine has a diagnostic port, there's plug and play devices that monitor engine and transmission perimeters and some offer alarms. At minimum I recommend replacing factory heat sensor and gauge or installing one in tandem.
Diesels require a narrow band of temperature to preform and to stay within that band engine must stay within a given rpm range. Violate that rpm and bad things start to happen. When a spike is noticed such as in this case, the solution is often simply catching next lower gear while maintaining rpm power band. The effect is almost immediate, you will see gauge begin dropping. The problem with many factory sensors and gauges is they give an aporoimation,not precise increments. I've operated tractors and trucks for decades but must rely on accurate heat gauge for quite some time on new to me for optimum gear and rpm. That's my 2 cents,spend them on a nice gauge and watch it to extend life of your new diesel.

 

[GeoHorn]

I have a L4400 HST 4WD, 800ish hours. I have noticed lately that my temperature gauge is running high when bush hogging. I have been mowing a 3 acre lot next to me for the lady that purchased it.

It stays in the white top of the white bracketed area just below the red. In other words the needle is in the top white bracket/boundary. I just do not remember it being that high in years past. It only does this when mowing, not post hole digging, fork usage etc.

Conditions are hot 90+ with little to no wind. All fluids are fine, no debris blocking air flow to the radiator. Grass is only about knee high. Blades on BH are 4-5 years old with little usage, since I purchased a bigger/faster zero turn for mowing. No bogging down, etc.

I don’t know what the “color ranges” are in your model tractor. (My own Kubota has no color-bands…it has a “C”… an ‘H” ….and an Index-mark at the mid-point…where my tractor spends most of its time when operating…and NEVER goes above that mid-line index.

My personal advice (based on a career of engine maintenance on other types of machines) is to AVoid harsh radiator “cleaners”. Over a 50-year experience working on engines…it took me only about 3 events of using a major-brand “cooling system flush/cleaner”…. Each of which resulted shortly thereafter with a Water-Pump-Failure.

Since then, I’ve only used plain water for a flushing or cleaning solution.

IF YOU PURCHASED your tractor “used”…. there may be no telling what coolant is actually in your system. If it’s not an Ethylen-Glycol Anti-Freeze/Coolant …or if it’s not in a 50% mix of coolant/water…. then your operating temps may be suffering.

Drain and flush the system with plain water, then service it with a reputable brand of Ehylene-Glycol Anti-Freeze and Distilled-Water ….(or select a pre-diluited version) …. and confirm your gauge indications with a reliable thermometer or infra-red tester …comparing the engine block at operating temperature to the upper and lower radiator areas.