L2500 Overheating?

[Ledge]

Hello,
I am new obviously and new to the Kubota L2500. I have pretty much zero experience with tractors. I do know basics on most mechanical engines but I am far from a mechanic. This may be a little long but please bear with me. here is my situation:

My dad bought this tractor new probably at the most 10 years ago and he just used it to work in his small garden. It came with the front loader attachment. He passed away from Leukemia two years ago this week. The tractor has been garage kept and used sparingly by my brother. It is in excellent shape. New battery, coolant is topped of and looks perfect. Plenty of oil but could use a change I am sure.

Here is the issue:
It starts and runs fine. I was using it to bush hog this weekend in temperatures in the upper 80's. The temperature gauge climbed pretty quick all the way over to the red area next to the H and almost pegged. I shut off, checked the mesh filter in front of the radiator and it was clean. I removed the mesh and checked the radiator itself and it was perfect. not dirt or debris in the fins. I did not notice and coolant bubbling or streaming out of the relief tube (this is what I call it, I don;t know the correct terminology for it). I have a feeling it may not actually be running hot but I don;t want to chance it and tear up my dad's tractor which I definitely couldn't afford to fix such as a rebuilding a motor.

Does anyone have any thoughts that maybe there is a problem with the gauge or is this thing really getting hot? What I am asking for is advice on what I should do. You will have to speak in very common lay-men's terms because I am very limited on terminology for parts, systems and tools. I have a lot of bush hogging to do for deer hunting. I am keeping the RPM at about 2000 with the PTO within the correct range (540) and I have tried it at different speeds to see if that helped to no avail. I can shut the tractor off and cools pretty quickly but the temp gauge rises pretty quickly too. Any ideas? Thanks very much for any ideas you can offer.

Lee

 

[clay45]

How do the fan/belt look?

 

[rentthis]

When you checked the radiator, did you just see the part visible behind all the sheet metal etc. Be sure you look through all of the radiator. You might have to remove some stuff to see it all. If some portion of it is actually clogged, usually around the outside edges, it will tend to heat up. Make sure you can see light through all of it. If not, compressed air will often blow it out. I remove radiators and clean them relative to what is in them. Don't use a pressure washer. It will destroy your radiator. Before you do any of that, do as clay45 suggested. a loose or bad fan belt will do the same thing.

 

[Ledge]

I removed the square wire mesh holder with the foam top and sheet metal side and cleaned it. This exposed the radiator cooling fins and they all looked clear. I did not check the fan belt. Since it wasn't actually releasing coolant through the relief tube, do you really think it's getting hot or could it be a faulty reading? Thanks for your help.

 

[85Hokie]

I removed the square wire mesh holder with the foam top and sheet metal side and cleaned it. This exposed the radiator cooling fins and they all looked clear. I did not check the fan belt. Since it wasn't actually releasing coolant through the relief tube, do you really think it's getting hot or could it be a faulty reading? Thanks for your help.

first thing .....
go to your nearest lowes....or home depot or harbor freight, or amazon if need be - get cha one of these :

http://www.homedepot.com/p/General-Tools-Mini-Infrared-Thermometer-IRT3/205519139

check all points of the system - top of radiator, bottom, head.....anything that you can "shoot"

you can do a hand test too - the top of the radiator should be "hot" but you ought to be able to touch it for .5 second and see if it real hot or just hot!

top of radiator when good and hot, not overheated - but rather "hot - normal" will be around 200F and the bottom 30-50 degrees less -

you could have a faulty reading meter, you could have a loose belt, or bad water pump or.....

another "test" - pop the radiator cap off - make sure coolant is where it should be, fire up the tractor and watch the coolant........any bubbles???? if so, bad news.....if not - then watch it more , it should not get hot in less than 2 or 3 minutes..

if it starts to burp up quickly or bubbles - you have a head gasket problem, if it starts to rise over 4-5 minutes, that is ok.

need to find out if the gauge is correct before digging into the ol girl!

report back what you find

 

[Ledge]

first thing .....
go to your nearest lowes....or home depot or harbor freight, or amazon if need be - get cha one of these :

http://www.homedepot.com/p/General-Tools-Mini-Infrared-Thermometer-IRT3/205519139

check all points of the system - top of radiator, bottom, head.....anything that you can "shoot"

you can do a hand test too - the top of the radiator should be "hot" but you ought to be able to touch it for .5 second and see if it real hot or just hot!

top of radiator when good and hot, not overheated - but rather "hot - normal" will be around 200F and the bottom 30-50 degrees less -

you could have a faulty reading meter, you could have a loose belt, or bad water pump or.....

another "test" - pop the radiator cap off - make sure coolant is where it should be, fire up the tractor and watch the coolant........any bubbles???? if so, bad news.....if not - then watch it more , it should not get hot in less than 2 or 3 minutes..

if it starts to burp up quickly or bubbles - you have a head gasket problem, if it starts to rise over 4-5 minutes, that is ok.

need to find out if the gauge is correct before digging into the ol girl!

report back what you find

Will get the tool today and check the tractor this weekend. it's a hundred mils from me. Thanks so much!

 

[Ledge]

I have another question if you all don't mind. Would running the PTO with a bush hog at lower than 540 RPM cause the engine to overheat?

 

[85Hokie]

I have another question if you all don't mind. Would running the PTO with a bush hog at lower than 540 RPM cause the engine to overheat?

the amount of WORK that the engine is doing has a direct relationship to the heat that is generated. If I run my B7100 around it will get to about 175-180, if I run the MMM - it will climb to 200......

Running it lower should not make it run hotter - now lower, you are not lugging the engine are you?

Placing the LOAD on the engine will increase the heat that it generates.

 

[ShaunRH]

Bush hogging is hard work, especially if the weeds are really high. What gear were you running it in? What size is the mower?

If all is good, I'd suggest slowing it down a bit and trying again. If the temps stay down, you are overworking that 25hp motor at higher speeds.

PTO should stay at 540, no faster, no slower. The mower is designed to operate at that speed (Tip speed of cutter affects rate of feed). You vary the speed of the tractor with the gears or HST pedal to control the feed rate of the material into the mower. If you are out of the proper operating range of the mower your engine will overheat.

 

[RCW]

Lee - locate the temperature sending unit on the engine and make sure the connection is clean and tight.

 

[Ledge]

the amount of WORK that the engine is doing has a direct relationship to the heat that is generated. If I run my B7100 around it will get to about 175-180, if I run the MMM - it will climb to 200......

Running it lower should not make it run hotter - now lower, you are not lugging the engine are you?

Placing the LOAD on the engine will increase the heat that it generates.

Not lugging the engine. Running around 2000 RPM but this is at the very low end of the PTO 540 range indicator on the dial.

Bush hogging is hard work, especially if the weeds are really high. What gear were you running it in? What size is the mower?

If all is good, I'd suggest slowing it down a bit and trying again. If the temps stay down, you are overworking that 25hp motor at higher speeds.

PTO should stay at 540, no faster, no slower. The mower is designed to operate at that speed (Tip speed of cutter affects rate of feed). You vary the speed of the tractor with the gears or HST pedal to control the feed rate of the material into the mower. If you are out of the proper operating range of the mower your engine will overheat.

The weeds are high. About 4' and thick. I had the mower in various ranges and speeds. Mostly in the high range in 7th gear at 1900-2000 RPM and the mower appears to be a 60".

Lee - locate the temperature sending unit on the engine and make sure the connection is clean and tight.

This I will do Saturday.



Thanks very much all!

 

[RCW]

The weeds are high. About 4' and thick. I had the mower in various ranges and speeds. Mostly in the high range in 7th gear at 1900-2000 RPM and the mower appears to be a 60".

Lee - no familiarity with your tractor, but hoggin' 4-foot thick stuff in 7th-high range sounds pretty quick to me.

I even use low range on my little BX w/MMM for real tall/heavy stuff.

Hokie and Shaun could be on to something....

 

[Daren Todd]

Bump your rpms up to the 540 mark on the tach. On four foot tall stuff, i'm usually running in low range, 4th gear or slower depending on how thick the stuff is. The thicker it is, the slower I go. It gives the stuff a better cut, and less stress on the tractor and implement. On dad's l2250, I would go up to fifth gear while bush hogging fields. Sometimes 6th gear, If it was only two to three foot tall. 7 and 8 were used only as transport gears between fields, and were too fast for implement use. Course we had the occasional boulder to watch out for, and would have to run the fel 6" off the ground to find them Finding one of them boulders in 7th gear hurt!!!

 

[Ledge]

Good stuff guys! I used a different tractor last year and could move faster. Hopefully all of this is my driving and not the tractor. I have about 31,500 square feet to bush hog.

 

[ShaunRH]

The weeds are high. About 4' and thick. I had the mower in various ranges and speeds. Mostly in the high range in 7th gear at 1900-2000 RPM and the mower appears to be a 60".

That sounds way too fast, but I can't directly relate that to my unit as it's an L3200, but I can tell you that in 4th gear on my 32 hp machine with a 60" mower and 3'-5' high weeds my unit starts to overheat. I mow in 3rd gear and take my time and it never goes above mid point. I also clean the radiator screen every hour, and blow out the radiator itself daily with a shop vac.

You could probably get away with your setup if your mowing was only about 6"-12" in height. Then it's only cutting the material and not having to mulch it much. So you can mow more often, but faster, or mow less often but slower.