L2650 overheating

mickey harmon

New member

Equipment
L2650
Jun 18, 2019
13
0
1
bartlett
This has been an issue for me since I purchased an l2650, new in 1991. The tractor seems to run hot under what I would consider a little bit of a heavy load ,cutting grass a little taller than normal,with grooming mower, or brush hog. It is my understanding that the L2650 runs in reverse so that air is pulled across the motor and then thru the radiator. I was just wondering if this is just a bad design on Kubota or am I just expecting too much from an L2650.
 

mattwithcats

Active member
Jun 17, 2017
777
66
28
Virginia
Putting a larger oil filter on may help.

You have an HH164-32430 oil filter, try Wix 51515, 51515XP, or even larger 51773.

Look on RockAuto for good prices...

What oil viscosity are you running?
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,249
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113
Sandpoint, ID
This has been an issue for me since I purchased an l2650, new in 1991. The tractor seems to run hot under what I would consider a little bit of a heavy load ,cutting grass a little taller than normal,with grooming mower, or brush hog. It is my understanding that the L2650 runs in reverse so that air is pulled across the motor and then thru the radiator. I was just wondering if this is just a bad design on Kubota or am I just expecting too much from an L2650.
How hot?
And how have you measured it?
Does it burp into the overflow?
 

rbargeron

Well-known member
Lifetime Member

Equipment
L5450, L48, L3250, L345 never enough attachments
Jul 6, 2015
1,171
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western ma
This has been an issue for me since I purchased an l2650, new in 1991. The tractor seems to run hot under what I would consider a little bit of a heavy load ,cutting grass a little taller than normal,with grooming mower, or brush hog. It is my understanding that the L2650 runs in reverse so that air is pulled across the motor and then thru the radiator. I was just wondering if this is just a bad design on Kubota or am I just expecting too much from an L2650.
Kubota has used forward air flow some models and rearward on others. There shouldn't be much difference in performance if the thermostat is working ok and the screen/debris net isn't plugged. In the old days some tractors had reversible blades for summer/winter operator comfort. Air flow direction was a customer option on Caterpillar.
 

mickey harmon

New member

Equipment
L2650
Jun 18, 2019
13
0
1
bartlett
I just watch the temp gauge, and it has red lined in the past but I don't let it go that far now. I let it cool off. I use the specified oil 10 w 30 I think. and I clean screen and radiator after each use. using a different size oil filter sound interesting. I even have thought of an oil cooler but haven't seen one.
 

North Idaho Wolfman

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Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,249
6,407
113
Sandpoint, ID
I just watch the temp gauge, and it has red lined in the past but I don't let it go that far now. I let it cool off. I use the specified oil 10 w 30 I think. and I clean screen and radiator after each use. using a different size oil filter sound interesting. I even have thought of an oil cooler but haven't seen one.
You need to get a separate physical measurement on it, as it could just be lying to ya. ;)
Top and bottom of radiator is good measurement locations to get and idea what is really going on, using a laser temp gauge.
 

mickey harmon

New member

Equipment
L2650
Jun 18, 2019
13
0
1
bartlett
It could be lying a little, but when you can hear it boiling, I think its hot. Other than the over heating, its been a great tractor. I just can't let my pasture go an extra week or two. It's only 10 acres, so I just have to stay on top of it. I was wondering if I should put some kind of in line temp gauge on it.
 

rbargeron

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Equipment
L5450, L48, L3250, L345 never enough attachments
Jul 6, 2015
1,171
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western ma
Letting it boil isn't doing the engine any favors. A temp sensing tool like these is under $10 - a lot cheaper than a head gasket and/or warped head.

Is the thermostat still in it? Try running without it. It only takes a few minutes to take it out - located where the top radiator hose connects to the engine. Unbolt the 110 cover (see attachment), take out the thermostat 140 and put the cover back on without it.

Assuming it will now run cooler, put the thermostat in a saucepan of water and bring it to a boil - see if it opens. If it doesn't a new one is around $17.
 

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man00

Member
Jul 3, 2013
197
12
18
okla
I remember reading dozens of I think my bike is running hot in the motorcycle forums. The question was always ask if the bike puking antifreeze? 99.9% of the time the answer was no...In that case it was determine the fix was black tape.
Out black tape over the gauge and that seem to fix most issues. Not saying that is your problem
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
5,214
1,899
113
Mid, South, USA
If it's boiling, either it's REALLY hot (like 260+)--assuming 50/50 mix of green antifreeze and distilled water, OR it could be that the system is not holding pressure, which will affect the boiling point. That could be a pressure cap not working correctly or the top of the radiator not sealing against the pressure cap, or obviously a leak somewhere causing pressure loss.
 

Pau7220

Well-known member

Equipment
L3650 GST, Landpride TL250 FEL w/ Piranha, 6' King Kutter, GM1084R Finish
Aug 1, 2017
785
278
63
Scranton, PA
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