Kubota engine cooling problems

DiezNutz · Jul 27, 2007

Under *normal* circumstances it would be more likely to overheat with the cap off/leaky cap. The cap keeps the system under pressure, thereby raising the boiling point of the coolant. The lower the boiling point of the coolant (bad or no cap), the more likely it is to...well...boil... instead of cooling the engine.

So I'm a little baffled at why it didn't overheat with the cap off, if the cap is the problem. I think as a number of us have already suggested, there are multiple factors at play here... for instance we still don't know the effect of the right-sized battery.
SkunkWerx's suggestion of making incremental and systematic changes and observing the results is the right way to proceed.

BMXER10 · Jul 27, 2007

DiezNutz said:
Under *normal* circumstances it would be more likely to overheat with the cap off/leaky cap. The cap keeps the system under pressure, thereby raising the boiling point of the coolant. The lower the boiling point of the coolant (bad or no cap), the more likely it is to...well...boil... instead of cooling the engine.

So I'm a little baffled at why it didn't overheat with the cap off, if the cap is the problem. I think as a number of us have already suggested, there are multiple factors at play here... for instance we still don't know the effect of the right-sized battery.
SkunkWerx's suggestion of making incremental and systematic changes and observing the results is the right way to proceed.

I have come to the conclusion that its a woman. Thats why its unpredictable. I cranked it up, let it sit for 10 minutes at full throttle. It didnt heat up very much at all. So I hopped on it, turned the deck on and drove around the yard for another 15 minutes, still stayed at a low temp.

The grass is going to be at normal height on saturday so im going to cut it, wish me luck.

DiezNutz · Jul 27, 2007

BMXER10 said:
I have come to the conclusion that its a woman.

Hmm... that would cover all the angles in that old expression about having trouble with anything with tires, or other things. Good luck.

milkman · Jul 28, 2007

BMXER10 said:
I have come to the conclusion that its a woman. Thats why its unpredictable.

When you get tired of fooling with her, I'll give you what you paid for her plus what you you paid for parts and come load her up and get her out of your hair.

At least she heats up quick.

BMXER10 · Jul 30, 2007

Well it was really freaking hot on Saturday with lots of humidity. I set the cutting height pretty low so the tractor got a good workout. It took a long time to heat up this time. You can see the before and after picture. Its definitely running cooler! I think its still running a tad hot, but Im honestly not sure where it should be running at since its always run hot.

BEFORE:

AFTER:

DiezNutz · Jul 30, 2007

That's still a bit too hot (assuming your sender & gauge work properly). Did you notice the coolant boiling as before?

BMXER10 · Jul 30, 2007

DiezNutz said:
That's still a bit too hot (assuming your sender & gauge work properly). Did you notice the coolant boiling as before?

It couldnt hear the boiling sound that I was getting before. The overflow tube never let any fluid out this time either.

Im pretty sure this gauge is accurate. It would never let fluid overflow until right when the gauge hit that red line. Any way to test it???