BX2360 nearly overheating issue

[SDMauler]

Hey all. I have a 2009 BX2360 with a 60" MMM. After mowing for about an hour, the temp gauge slowly creeps to the top of the scale, and then stays between 95-100% of the white range. It never actually boils over, (because I stop mowing before it does) but I can't imagine this is good for the longevity of the engine. If I idle it down, it does slowly cool down, but as soon as I start mowing again, it starts to heat up.

I've changed the thermostat, and refilled with new antifreeze. This heating issue usually only happens when mowing ( probably the longest, heaviest consistent load the tractor sees). The coolant in the radiator gets hot, so at least some circulation is happening. I've checked the radiator fins, blown them out with air, and I can see right through them. The mower deck has a new belt on it this year, and is well greased, and turns easily. The air filter is also new, and when it lugs down in heavy cutting, it has a little black smoke, so I think it's getting plenty of fuel.

Before I throw a lot of parts and money at this, has anyone ever had a similar problem with this tractor? Anyone experienced a bad water pump? It doesn't leak, or make noise. Any other ideas?

Thanks in advance to the Orange Tractor Wizards of Smart.

 

[ShaunRH]

...

Before I throw a lot of parts and money at this, has anyone ever had a similar problem with this tractor? Anyone experienced a bad water pump? It doesn't leak, or make noise. Any other ideas?

See the post under What did you do on your Kubota today for flushing your radiator fins. Barring that being an issue, you can lose a water pump even without it leaking or making noise. Some anti-freeze components or really old anti-freeze, can melt down the impellers on a water pump (especially if it's aluminum!)

Friends of ours had a Ford Taurus that kept overheating. Even the dealership declared they couldn't fix the issue. My father told them he thought it was the water pump, everyone said it couldn't be, it didn't leak and didn't squeak. My dad took it off anyway. Low and behold, no pump impeller, eaten clean away, just a stub of the shaft left. Enough to hold seal and rotate nicely. Replaced the pump and issue solved. The dealership had major egg on their faces, ended up refunding our friends diagnostic money he paid them.

Moral of the story, use aluminum friendly anti-freeze and change it fairly often!

 

[rentthis]

Check to see if your fan belt is tight. It may be tight and in need of replacement. They will harden and slip in the pulleys. Over heating is often the only sign of a problem. When you looked through the radiator, did you see through the entire radiator or just the center. They tend to fill up on the sides and restrict air flow enough to do what you describe. You might also check you blades for sharpness.

 

[85Hokie]

Check to see if your fan belt is tight. It may be tight and in need of replacement. They will harden and slip in the pulleys. Over heating is often the only sign of a problem. When you looked through the radiator, did you see through the entire radiator or just the center. They tend to fill up on the sides and restrict air flow enough to do what you describe. You might also check you blades for sharpness.

90% of overheating is due to the radiator NOT being completely cleaned out.
Compressed air - and more and more compressed air - would not use water, it will gel with the chafe and then be harder to get out.

AS rent said - check the belt - believe it or not a slipping belt is an easy overlook - check and see if tight.

Anti freeze is great stuff, but here is the rub....the more antifreeze you have in the system the LESS is will cool ......I know that sounds crazy as hell, but the best thing would be to do is place straight water in there....but then again that would be bad cause there is not any "good" stuff in water to lubricate, if in a warm climate - I would go 20% or 30% antifreeze. (you cannot in your place other than dead of summer)

On a non pumped system - like the thermosyphon systems - it does make a difference - up to 20 degree (F)

but I would imagine that you have one of the prior problems....
fix:
clean radiator
tight belt
new mix

see what happens - might be a stopped up radiator too.....

 

[ShaunRH]

Compressed air - and more and more compressed air - would not use water, it will gel with the chafe and then be harder to get out.

On a newer tractor, I'd agree with that, but older units that have never been cleaned (or rarely cleaned) need something to get the gunk to 'unstick'. You could be blowing with that air all day and it would never unstick. Air alone might do it if there's no clingy dirt involved. The water lets the gunk go solvent, (or gel if you like) and then if you hit it with compressed air, it blows the gel/water/gunk all out in one shot. Rinse and repeat and you have a clean radiator.

Even if completely caked with mud/oil, you'll still need water and solvents to get the fins cleaned up. If it's really bad, you'll have to take it off and soak it for at least a day in solvents/detergents to get it to loosen all the crap up.

It can be a process for a really bad radiator. However, in his case it's probably just a good flushing.

 

[85Hokie]

On a newer tractor, I'd agree with that, but older units that have never been cleaned (or rarely cleaned) need something to get the gunk to 'unstick'. You could be blowing with that air all day and it would never unstick. Air alone might do it if there's no clingy dirt involved. The water lets the gunk go solvent, (or gel if you like) and then if you hit it with compressed air, it blows the gel/water/gunk all out in one shot. Rinse and repeat and you have a clean radiator.

Even if completely caked with mud/oil, you'll still need water and solvents to get the fins cleaned up. If it's really bad, you'll have to take it off and soak it for at least a day in solvents/detergents to get it to loosen all the crap up.

It can be a process for a really bad radiator. However, in his case it's probably just a good flushing.

Shaun.

all very true - sometimes I have used aluminum cleaner and something like 409 to soak in there......wetting will loosen some of that stuff up!

that grass and chafe is a PITA to get out when wet and compacted !

 

[ShaunRH]

that grass and chafe is a PITA to get out when wet and compacted !

Agreed, but once it mixes with dirt and sticks, it's time for a soak. Eventually it blows out, makes a gawdawful mess doing it too... don't ask me how I know... just don't ask... yuck!

 

[skeets]

Simple green 50/50 mix, Take the mesh cover off in front of your feet where the batter hides, remove the battery and you will have access to the back side of the rad, open the hood and remove the protective screen that slips down in front of the rad, wash it off with simple green and let it sit,, then from the back side shoot the mix on the rad, and then go around front and do the same thing as much as you can get. Go have a cup of coffee or an adult beverage and sit for a bit. The with a garden hose NOT A PRESSURE WASHER squirt out the cooling fins from both sides. Then if you have a compressor and air gun blow it out or use a leaf blower. That should get rid of about 99% of the gunk on the rad. Put the cleaned screen back in place then replace the battery hook it up,, Positive lead first, then the negative one. And you replace the screen cover and you should be set to go

 

[North Idaho Wolfman]

Before you spend another dime on parts get a Laser thermometer and check the actual temp, it's not that uncommon for either the gauge or the sender to me lying on the actual temp, high on the scale could be still normal.

http://www.ebay.com/itm/NON-CONTACT...HT-HANDHELD-/130979214461?hash=item1e7ef8347d

 

[RCW]

Before you spend another dime on parts get a Laser thermometer

I'll second that.

I have the same model, and had a similar issue a couple times.

It really wasn't hot at all.

 

[SDMauler]

Thanks everyone, some very good points there. I took my laser thermo out there today after doing some grading. It wasn't as hot as when I mow, but pretty warm. The engine block was around 200 F, the upper hose and the top of the rad was around 160-165' and the lower hose was around 150-155. With only a 10 degree drop across the rad, I'm thinking its time for a more thorough de-grunging, inside and out. Instead of trying to do it on the tractor, I am thinking about taking the rad clear out, so I don't have to worry about the alternator or other electrical issues. That will also give me access to the water pump area, so I will inspect that while I'm at it.

I did check the belt, since I had to take the alternator out to get at the rad drain to replace the T-stat, so I don't think that's the problem. There is fresh 50/50 antifreeze in there, since I live in SD, I always run that mix.

Again, thanks for sharing your experience and knowledge.

 

[100 td]

A couple of things to consider.
When you did your IN/OUT temp readings, was the engine running at full speed? If it wasn't, then your readings are no giving you a true indication as there is significantly reduced air flow through the radiator.

Correct me if I'm wrong, I believe your tractor has a radiator overflow bottle, if it does, it is designed to allow fluid to be expelled during heating and go into the overflow bottle and to be drawn back into the radiator when it is cool. This allows the expulsion of air from the engine cooling circuit and ensures it is full of "fluid" at all times.
Monitor the level of the overflow tank when hot and cold, and ensure it never gets below the minimum level after being left sit overnight. Also first thing in the morning, check the radiator fluid to ensure the radiator has drawn fluid (not air) back into the radiator, so it should be full right to the top when you open the radiator. If it has air space you have a leak somewhere. Ensure there are no loose hose connections between the radiator and the overflow bottle, and that the hose into the overflow bottle goes all the way to the bottom, or just off the bottom as designed.

Temperature gauges in modern cars have a "dead band" built in to their circuitry, so that drivers do not see the temperature fluctuating up and down as the engine heats and cools, they read warm for a wide variety of temperatures. They are designed this way so they do not get every mum and dad ringing up and saying their car is hot after a bit of towing or sitting in traffic etc.
Industrial gauges should not have this dead band and you see what the temperature actually is, and it will fluctuate up and down greatly. Whether OEM Kubota gauges have this feature or not I am unsure.

Remember that your cooling circuit is pressurized and is designed that way to increase the boiling point of the fluid so the fluid does not boil at 212F. So a 0.9 kg/cm sqrd or 13 psi cap will raise the boiling point to 250F approx.

By all means clean your radiator some more, but they are designed to operate with general environmental contaminants on them. Run your tractor at full load and observe the temperature and observe the overflow bottle and use your IR thermo when the tractor is hot to see if the radiator is cooling effectively and what the actual temp of your fluid is. By all means pull your water pump if you suspect it, but you may be able to see a generous flow when it is warmed to operating temp by looking in the radiator. Good luck.

 

[SDMauler]

100:
Thanks for your insight. I will repeat the readings while running at full power, after its good and warmed up, and with a full air flow across the radiator. It does have an overflow bottle, which I keep near the full cold mark. The radiator is always full to the top when I open the cap.

Thanks.