Overheating problems

[85Hokie]

Thanks for the info. I just picked up a new infrared thermometer. I will check and get some more accurate readings and let you know what I find out. Thanks

You cant do it while putting around the yard - work that machine THEN get the readings.

 

[GeoHorn]

If the coolant is correct it won't boil at 220.

Dan

OK..well, technically, a 50/50 mix of ethylene glycol will not boil until 223-F…. but, perhaps you meant that if the “Pressure” is correct….I.E. the radiator cap is rated at (example) 13 psi…it actually HOLDS 13 psi. Coolant will require higher than ordinary boiling points if under pressure… for every 1 psi over atmosphere the boiling point will increase by approx 3-degrees F.

 

[TheOldHokie]

OK..well, technically, a 50/50 mix of ethylene glycol will not boil until 223-F…. but, perhaps you meant that if the “Pressure” is correct….I.E. the radiator cap is rated at (example) 13 psi…it actually HOLDS 13 psi. Coolant will require higher than ordinary boiling points if under pressure… for every 1 psi over atmosphere the boiling point will increase by approx 3-degrees F.

No I meant exactly what I said.

The boiling point of a 50/50 coolant mix is 226F at sea level. It increases by 2.25 degrees F for every pound of pressure. The radiator cap is +13PSI which man's it won't boil until 255F. In the course of my life I have owned multiple clunkers that routinely ran 220F in the summer. I didn't worry until things started getting a good bit hotter.

Dan

 

[RCW]

^^^^^^^
Grandma used a pressure cooker for a reason…..

 

[GeoHorn]

Why is the cooling system under pressure?

help.summitracing.com

.

 

[oberon4]

Not trying to hijack the thread but I have a similar issue. I think I tried everything except straitening the fins. I got some temperature reading right before the engine overheated. Could someone take a look to see if the numbers don't make sense? Thank you! (the pictures were taking with removed thermostat).

 

[DaveFromMi]

Not trying to hijack the thread but I have a similar issue. I think I tried everything except straitening the fins. I got some temperature reading right before the engine overheated. Could someone take a look to see if the numbers don't make sense? Thank you! (the pictures were taking with removed thermostat).
View attachment 110498 View attachment 110497 View attachment 110496

No or little coolant flow through the radiator. Bad water pump, plugged radiator tubes, or stuck thermostat.

 

[oberon4]

No or little coolant flow through the radiator. Bad water pump, plugged radiator tubes, or stuck thermostat.

Tstat is new so let's not consider it. Can I assume that water pump works based on the fact that coolant is coming through the bottom pipe? The radiator is not in the best shape but should I see the radiator tubes to be hotter than fins on the thermal image (I am thinking to bring it to a shop to rod out but don't want to spend money if it's not strictly necessary)?

 

[DaveFromMi]

Tstat is new so let's not consider it. Can I assume that water pump works based on the fact that coolant is coming through the bottom pipe? The radiator is not in the best shape but should I see the radiator tubes to be hotter than fins on the thermal image (I am thinking to bring it to a shop to rod out but don't want to spend money if it's not strictly necessary)?

Try this first. Could be a cheap solution.

Prestone® Total Cooling System Cleaner

Designed to help defeat heavy rust and scale deposits in neglected cooling systems.

prestone.com

 

[603g5200]

If you have replaced all those parts and you can hear bubbling when it is running, it sounds like you water pump is bad. Pull the thermostat out, disconnect the upper radiator hose have someone hold it into a clean bucket start the tractor and see if coolant flows, if not replace your pump.
Kubota #15852-73036

 

[evan waa]

Thanks for the info. I just picked up a new infrared thermometer. I will check and get some more accurate readings and let you know what I find out. Thanks

I have had overheating problems with both a bx22 and a bx2200 tried a lot of things and still not really satisfied with the results but my best change in the system was to take a fan from a BX 2680 which is a five blade fan turn it down slightly and put that in air flow has increased and a cooling is somewhat better thank you

 

[NorthwoodsLife]

Many eons ago, my b7100 started overheating. It was simply dirt in the radiator fins.
As someone else mentioned... Did you clean the external radiator fins?

 

[NorthwoodsLife]

Some older Kubotas don't have a water pump at all. Simply runs on thermal convection

 

[JayBee]

Thanks for the info. I just picked up a new infrared thermometer. I will check and get some more accurate readings and let you know what I find out. Thanks

Hi there- new to the forum- I have had a g5200 for 20years and struggled with heating temp for a long time, it slowly got worse. after changing everything you have mentioned and reconditioning the radiator, it turned out to be the water pump. On first inspection of water pump removed the cast iron impellor and it looked ok, however , looking closely it had eroded from the center of of the shaft. I changed the pump and it now runs great. By the way it is also fitted with a larger a 54" deck. I hope this helps many people with heating/ cooling problems on these little tractors.