Oil & Fuel How important are 300 hour HST oil changes for Kubota B7510 used as a mower?

[Trials]

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If you truly believe that HST oils are not subjected to high temps you lack an understanding of that type of system. Improper operational methods can result in high oil temps and temperature related oil and component failure.

Please feel free to comment on what I actually said.

 

[Trials]

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True ... but largely irrelevant.

Have you ever seen transmission oil turn dark black like engine oil does?

 

[RickB]

Please feel free to comment on what I actually said.

I have. Actually I quoted you directly.

Review your post #8 in this thread where you claim HST oil is not subjected to extreme high temperatures.

 

[Trials]

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If you truly believe that HST oils are not subjected to high temps you lack an understanding of that type of system. Improper operational methods can result in high oil temps and temperature related oil and component failure.

You missed the word extreme :/ Do you know what the combustion temperature of diesel fuel is, and do you know the maximum acceptable operating temperature of the oil in a hydraulic system?

 

[RickB]

You missed the word extreme :/ Do you know what the combustion temperature of diesel fuel is, and do you know the maximum acceptable operating temperature of the oil in a hydraulic system?

Most common tractor hydraulic oils exhibit heat stress when heated to between 185 and about 200 degrees F for extended periods. Most Hyd oil temp warning systems will activate in that range. Conventional wisdom wants to keep hydraulic oils no more than 100 degrees F above ambient.
I don't know offhand what the combustion temp of fuel oil is and frankly I don't care.

I have smelled cooked oil in hydrostatic transmissions and seen resulting damage to swash plates, slippers and pistons. Do you know the definition of extreme?

 

[RickB]

Have you ever seen transmission oil turn dark black like engine oil does?

Yes..

 

[Trials]

The two major pollutants of diesel combustion are carbon (that's the black stuff) and sulphur acids (that's the stuff that eats your engine up real quick and compels you to change your engine crankcase oil frequently) Neither of these chemical contaminants should be finding their way into your transmission in appreciable quantities or the associated hydraulic systems. If your hydraulic oil is turning black like your engine oil does and contains high volumes of sulphurous combustion residue, you have a serious problem.

 

[RickB]

The two major pollutants of diesel combustion are carbon (that's the black stuff) and sulphur acids (that's the stuff that eats your engine up real quick and compels you to change your engine crankcase oil frequently) Neither of these chemical contaminants should be finding their way into your transmission in appreciable quantities or the associated hydraulic systems. If your hydraulic oil is turning black like your engine oil does and contains high volumes of sulphurous combustion residue, you have a serious problem.

Your knowledge gap is widening. Everything you may know about internal combustion does not translate directly to what you think you know about hydrostatic transmissions.

Good day to you.

 

[Trials]

Good grief, you just don't get it do you :yo-yo:
Good day to you too.

 

[Billrog]

Trials every one is entitled to an opinion and I personally don't take offence to any comments contrary to mine. I expressed my opinion based on a tractor I owned from new since 1990 that kept 4k of mt. trails open all winter plowing snow & a 1/2 k of driveway. During the summer logging and brush hogging a min. of 20 acres. Not much of - 20 or 30 but -10 not uncommon and a wk here and there of - 20 to -30 on occasion.
The tractor was kept under cover ( just a roof ) but always plugged in with a timer to warm it up 4 hrs. before use. The engine oil & filter every 100 hrs. because the darn thing only held 3 lt. of oil.