B7500 Operating Temperature

[Clevus]

So this being my first Kubota I am operating within my learning curve. I bought this last year, used the mower deck frequently, pulled snow all winter. From day one I noticed the temperature gauge was not working. All winter I’m not really thinking much about as everything else works as it should. Now I see that the gauge is working but only comes up the the bottom of the “C”. Engine is running about 158°..

Before I start throwing parts at it, is it normal for a diesel like this to run that cold?
my first inclination is to change out the thermostat. At the same time I wonder if it might be the nature of the beast.

What say you, the oracles of the Orange Tractors?

 

[Roadworthy]

I've got the L2501 - different series, probably different engine. When it warms up completely it's at the bottom end of the "Cold" range. I bought it new. I've not put an actual temperature gauge on it but I do know tractors tend to run cooler than gasoline engines. Sit back and await more comments.

 

[Henro]

So this being my first Kubota I am operating within my learning curve. I bought this last year, used the mower deck frequently, pulled snow all winter. From day one I noticed the temperature gauge was not working.... Now I see that the gauge is working but only comes up the the bottom of the “C”. Engine is running about 158°..

How did you determine this temperature? Might help someone knowledgeable if you add this information.

My guess would be the thermostat. Could a previous owner have removed it? OR perhaps it is stuck fully open...

Both my tractors run mid range on the indicator, or higher if I fail to clean debris from the screen in front of the radiator.

 

[Rusty46]

Both my tractors run mid range on the indicator, or higher if I fail to clean debris from the screen in front of the radiator.

My B7500 temperature gauge works. It starts below the "C" line and gradually moves up to 1/4-1/2" above "C". When mowing dry or dusty grass, it will climb to the "H" zone as the debris screen before the radiator becomes more and more plugged. When the screen is cleaned, the indicator drops back to about center of the scale, and begins slowly (or not so slowly) rising again.

 

[Clevus]

How did you determine this temperature? Might help someone knowledgeable if you add this information..

handheld infrared laser dot. It’s pretty accurate.
Checked upper hose and side of block where the temp sensor is located.

 

[Russell King]

The temperature will stay low until the engine is under load so try mowing for a while and then see what the temperature is

I am assuming you are taking temp at idle or ambient was low during snow removal

 

[Henro]

handheld infrared laser dot. It’s pretty accurate.
Checked upper hose and side of block where the temp sensor is located.

Since the tractor meter and the infrared thermometer seem to agree...chance are the best first next step is to check the thermostat. Might not be in there, or if it is, it should be apparent that it is stuck open when you take it out...

You can also check it on the kitchen stove in a pan of water that you heat up while watching the thermostat. Not sure if they ever fail in the "open early" mode though.

 

[85Hokie]

Ideally - you want that diesel to get too about 200 F under a working load.

 

[Yogi]

How did you determine this temperature? Might help someone knowledgeable if you add this information.

My guess would be the thermostat. Could a previous owner have removed it? OR perhaps it is stuck fully open...

Both my tractors run mid range on the indicator, or higher if I fail to clean debris from the screen in front of the radiator.

My b7500 will run all day with out getting hot but as soon I start mowing the temp goes over over 200 degrees and after about 45 minutes it is boiling . I have tried everything , flushed engine new thermostat , keep radiator and scree clean,
nothing seems to work

 

[Henro]

My b7500 will run all day with out getting hot but as soon I start mowing the temp goes over over 200 degrees and after about 45 minutes it is boiling . I have tried everything , flushed engine new thermostat , keep radiator and scree clean,
nothing seems to work

Could the fan belt be slipping?

Old belt that looks good but reduced friction between the belt and the fan pulley so the fan just turns slower than it should?

Just a WAG...

 

[Savoy John]

Sounds like you have a 71c (159.8f) thermostat in it. I just recently found out my B-2710 has a 82c (179.6f) thermostat in it. I ordered a new thermostat thinking the original was stuck open. Took it out and tested it, worked fine. The new thermostat was stamped 71c. I wonder why they don't let the consumer know the temp before buying and why do they send the lower temp?