I just signed up here, hoping for some suggestions. I’ve got a U35 with overheating issues. I can’t figure out the exact cause so I’m looking for suggestions. The basics - this unit is my brother’s and bought new, 2005 with 1600 hrs. The unit has been maintained through the dealer and has only seen kubota parts and fluids. Current maintenance includes new radiator, new water pump, hoses, belts, thermostat, fuel filter and air filter. I’m reassembling now but have not found any identifiable cause of the overheating. I’ll have it together this wknd but any ideas would be helpful- also there were no signs of any corrosion inside the motor and the radiator showed only about 10% of the tubes had crust in them. Due to the overheating and age we’ve done a major maintenance upgrade. Next step will be to breakdown the exhaust system and check for restricted flow.
Seeking suggestions- U35 mini excavator overheating problem
- Thread starter UminiClyde
- Start date
Welcome to the forum. Sounds like you've thrown the parts cannon at it. Are you saying it still overheats after all that new stuff? Or you are doing all those parts to hopefully address the problem?
After it is back together and the anti-freeze system is bled do you have bubbles in the anti-freeze(head gasket or head issue possible) at the radiator cap? Is it actually overheating(bad sensor or wire connection). I have never seen an exhaust restriction cause an overheat issue(FYI Auto Tech. here) unless the catalytic convertor is plugged(I don't think it has one). Proper oil level as I have issues with overheating due to faulty injector, but that one ran very poorly(over-fueling). Has it changed in how it sounds when running?
dirtydeed
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B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
The first thing I'd try would be to verify that it's actually overheating (IR gun) or is it a faulty temp sensor? Would likely need to the workshop manual in order to get the correct resistance values to test the temp sensor(s).
Thanks for the suggestions. I did get it all back together and it started to overheat again within a few minutes. I was really trying to fix this without tearing into the motor. But with a friends advise(Bobcat mechanic), I pulled the head. The head gasket is the culprit. It’s a layered gasket, which can fail by letting hot gasses into the water and not letting the water into the oil. The head came off easily and is out to get checked for cracks and warpage. Note to anyone with a U35- don’t mess with the radiator it’s a nightmare to remove. Take care of the system! Lol