Warming HST oil VS engine oil
- Thread starter Henro
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torch
Well-known member
Equipment
B7100HSD, B2789, B2550, B4672, 48" cultivator, homemade FEL and Cab
That is unquestionably true to some extent, but does the BX25 not have a hydraulic cooler and fan as the primary method of cooling the hydraulic oil?
The trans will be just fine in even extreme cold temps with the proper fluid in it. Following the proper warm up process is arguably more important then worrying about preheating your transmission. The hydro fluid is something around a 10 weight oil, and the s-udt2 has an excellent low temp poor point. I'd personally be more worried about getting some heat in the engine cylinders and heat then worry about the trans.
It's a lighter then 25 weight. Kubota lists cst instead of a weight. It's actually closer to a 5 or 10 weight. 100cst is close to 30 weight oil. The 37 cst they list on their spec sheet is pretty thin oil. At either rate it has a poor point listed at -42* C. Which we can all agree is quite cold.
GreensvilleJay
Well-known member
Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
hmm... under 'typical properties'....pour point, *C MAX is -42
So the MAXimum temperature that you can pour the oil is MINUS 42 * C ?
Normal people would call that very,very COLD as the MAX (high) temperature and NOT be out on their tractors !
So the MAXimum temperature that you can pour the oil is MINUS 42 * C ?
Normal people would call that very,very COLD as the MAX (high) temperature and NOT be out on their tractors !
I think the term pour point implies that it is a minimum temperature.
Interesting thread, even if it's probably been covered many times.
As far as heating oil vs coolant, there is a significant difference: coolant is pumped by a centrifugal pump, and oil is pumped by a fixed displacement pump. One of those is a lot more likely to stress and break pumping thick fluid than the other (its the oil pump). Same statement is true for hydraulic pumps, both your regular 3pt/loader 'aux' type pumps, and the HST pump.
Now people may not have issues actually snapping tiny driveshafts to oil pumps on tractors like they do on cars, but the added force of pumping the fluid still accelerates wear, probably especially in small spaces where the thicker oil does not want to go, such as the 'thrust' surfaces in a gear pump etc.
Best thing you can do for cold weather is use fluid that has the lowest viscosity at that temp, which was already said in so many words.
Also, the power of a heating element was brought up. If you want something to work quickly it needs to be a lot larger than 150-250w. You can think of it in terms of space heaters since those are pretty relatable. Unfortunately we don't have a way to heat JUST fluid because the fluid is touching metal and will conduct heat to it. So even though we may only have gallons of fluid to heat, because we pretty much cant put heat in faster than the fluid can conduct it to all the metal its touching, we have to heat up maybe about 200lbs of stuff (fluid&metal) on a smallish tractor to get the fluid heated. If you imagine putting a typical '1500 watt' space heater under a 200lb block of ice, how long would it take to melt it? At that point it would be 32f/0c. We don't need to get all the way up there, but you can imagine it would take a long time, maybe 2+hrs? That's 1500w, now try 200w. That size of element needs to be left on 4+ hrs to put a dent in it, preferably just run it all night. And if you leave your tractor outside with the wind blowing even lightly, there's a good chance the tractor makes a good enough 'radiator' to lose heat as fast as a 200w heater can put it in. Thus the blankets and stuff some people use.
Unfortunately heating pads are usually going to be 'dumb' with no temperature sensing so even though a typical 120v/15a circuit can support about 1800w (this is why no 120v space heaters are rated over 1500w), you probably won't find a 1500w heating pad. You MIGHT find something that actually installs into a fluid sump and has built-in temp sensing so if someone were to use it in the summer it wouldn't heat the oil to 250f etc, but i just doubt it is available in most cases. There are large diesel heaters that will heat either air or liquid, but incorporating one into the fluid system would be pretty complicated and expensive. Now if you just roll a diesel torpedo heater up near the front axle of your tractor and let that blow under there for 10-20min, you've actually probably done a decent job taking the edge off, and a lot of people probably already own that thing! May want to think about how much of your tractor is plastic before attempting.. At Your Own Risk.
Long story short, if it is seriously cold and you want a block heater or heating pad to do anything, run it all night or at least more than half the night on a cheap timer plug.
Interesting thread, even if it's probably been covered many times.
As far as heating oil vs coolant, there is a significant difference: coolant is pumped by a centrifugal pump, and oil is pumped by a fixed displacement pump. One of those is a lot more likely to stress and break pumping thick fluid than the other (its the oil pump). Same statement is true for hydraulic pumps, both your regular 3pt/loader 'aux' type pumps, and the HST pump.
Now people may not have issues actually snapping tiny driveshafts to oil pumps on tractors like they do on cars, but the added force of pumping the fluid still accelerates wear, probably especially in small spaces where the thicker oil does not want to go, such as the 'thrust' surfaces in a gear pump etc.
Best thing you can do for cold weather is use fluid that has the lowest viscosity at that temp, which was already said in so many words.
Also, the power of a heating element was brought up. If you want something to work quickly it needs to be a lot larger than 150-250w. You can think of it in terms of space heaters since those are pretty relatable. Unfortunately we don't have a way to heat JUST fluid because the fluid is touching metal and will conduct heat to it. So even though we may only have gallons of fluid to heat, because we pretty much cant put heat in faster than the fluid can conduct it to all the metal its touching, we have to heat up maybe about 200lbs of stuff (fluid&metal) on a smallish tractor to get the fluid heated. If you imagine putting a typical '1500 watt' space heater under a 200lb block of ice, how long would it take to melt it? At that point it would be 32f/0c. We don't need to get all the way up there, but you can imagine it would take a long time, maybe 2+hrs? That's 1500w, now try 200w. That size of element needs to be left on 4+ hrs to put a dent in it, preferably just run it all night. And if you leave your tractor outside with the wind blowing even lightly, there's a good chance the tractor makes a good enough 'radiator' to lose heat as fast as a 200w heater can put it in. Thus the blankets and stuff some people use.
Unfortunately heating pads are usually going to be 'dumb' with no temperature sensing so even though a typical 120v/15a circuit can support about 1800w (this is why no 120v space heaters are rated over 1500w), you probably won't find a 1500w heating pad. You MIGHT find something that actually installs into a fluid sump and has built-in temp sensing so if someone were to use it in the summer it wouldn't heat the oil to 250f etc, but i just doubt it is available in most cases. There are large diesel heaters that will heat either air or liquid, but incorporating one into the fluid system would be pretty complicated and expensive. Now if you just roll a diesel torpedo heater up near the front axle of your tractor and let that blow under there for 10-20min, you've actually probably done a decent job taking the edge off, and a lot of people probably already own that thing! May want to think about how much of your tractor is plastic before attempting.. At Your Own Risk.
Long story short, if it is seriously cold and you want a block heater or heating pad to do anything, run it all night or at least more than half the night on a cheap timer plug.
nbryan
Well-known member
Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
-42C is the highest temp that it will still pour. Could pour at a lower temp.
TheOldHokie
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Lifetime Member
Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Pour point is the LOWEST temperature at which it will "pour" and the definition of pour is more like sag. ASTM test D97 is the standard procedure used to measure this property. This video is more than most people want to know:
Dan
GreensvilleJay
Well-known member
Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
I know what they're saying, but it's really,really bad way to say what they mean. While 'they' are talking about oil, glass also has a 'pour point', as do 1,000s of other materials like steel.
Really what's bad, is the use of 'MAX' in the description. To 99.44% of people 'MAX" is the HIGHEST a value will be NOT the lowest. Then again we've gone from logical MPG to l/100Km
Really what's bad, is the use of 'MAX' in the description. To 99.44% of people 'MAX" is the HIGHEST a value will be NOT the lowest. Then again we've gone from logical MPG to l/100Km
When you start at the middle of a range/scale…EITHER end is “Max”.
The claim made for Super UDT2 that intrigued me most was “efficient filterability”.
This implies it’s capable of being filtered efficiently. Ordinarily one would consider the efficiency of filtering to be more dependent upon the FILTER. But further consideration is that a high-viscosity (due to low temp) fluid containing dirt might not be capable of being pumped thru 30-micron filter-media without forcing-open a by-pass valve and thereby dumping previously-collected dirt back into the machinery….OR … completely causing the filter to collapse or BURST.
The bottom line is still the same: Kubota tells the customer which fluid they think is best for their machine….and any owner who uses anything else does so at risk. (Probably also applies to filter choices.… and grease types.)
The claim made for Super UDT2 that intrigued me most was “efficient filterability”.
This implies it’s capable of being filtered efficiently. Ordinarily one would consider the efficiency of filtering to be more dependent upon the FILTER. But further consideration is that a high-viscosity (due to low temp) fluid containing dirt might not be capable of being pumped thru 30-micron filter-media without forcing-open a by-pass valve and thereby dumping previously-collected dirt back into the machinery….OR … completely causing the filter to collapse or BURST.
The bottom line is still the same: Kubota tells the customer which fluid they think is best for their machine….and any owner who uses anything else does so at risk. (Probably also applies to filter choices.… and grease types.)
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nbryan
Well-known member
Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
How I interpret MAX in the data sheet is that the actual pour point MAY BE AT A LOWER TEMP THAN -42C.
That is the HIGHEST MINIMUM temperature that the fluid will pour at. It may pour at a temperature LOWER than -42C.
nbryan
Well-known member
Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Whatever you want to call it, it's how I read the information in the data sheet.
TheOldHokie
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Lifetime Member
Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
The data sheet is providing "typical" numbers so there is always a caveat/. On repeated testings formulations vary and test error creeps in. The MAX part in the data sheet simply indicates its a trusted number derived from multiple tests.
But D97 is not ambiguous. The reported number is 3 degrees C higher than the temperature at which the oil ceases to flow. You better not expect any given sample to flow below that point and no lubricants engineer would.
Dan