Why is NOACK/volatility loss a big secret?
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Originally Posted By: jaj
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose.
As I understand it, some of the more modern engines (Eg Honda CRV, IIRC) top up the sump automatically, (and relentlessly) with fuel.
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose.
As I understand it, some of the more modern engines (Eg Honda CRV, IIRC) top up the sump automatically, (and relentlessly) with fuel.
Originally Posted By: kschachn
Can you explain why I would care whether they are published or not? As long as I purchase an appropriate viscosity oil with the required ratings for my vehicle, why would I vote for full disclosure?
If you can keep close track of oil consumption per 1,000 miles and eliminate mechanical problems, you will get an idea of volatility. BTW, volatility and viscosity are directly related.
Can you explain why I would care whether they are published or not? As long as I purchase an appropriate viscosity oil with the required ratings for my vehicle, why would I vote for full disclosure?
If you can keep close track of oil consumption per 1,000 miles and eliminate mechanical problems, you will get an idea of volatility. BTW, volatility and viscosity are directly related.
Originally Posted By: jaj
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
In itself, the Noack volatility is a meaningless number. The test measures how much oil, when held at 250°C, evaporates into a stream of cold air over the course of one hour.
The reality is that your oil (typically at 100°C) might be exposed to a stream of hot blow-by for 300 hours. How much oil exits the crankcase with blow-by in this situation?
The answer depends on a whole host of variables? Do you drive modestly (like me) or in a spirited fashion (everyone else on BITOG)? Do you live in a non-extreme climate (like me) or do you live in a country that sees extremes of hot and cold? Do your engine see significant fuel dilution (from low tension rings, or because it's TGDI, or because you live in a cold climate?). Is your engine nice a tight (because it's relatively new) or worn out and letting through a lot of blow-by? Do you have a typical OCI of 3k miles or 15k?
I once ran an 11%-ish Noack oil of my own making and lost 40% of it over 15,000 miles!
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
In itself, the Noack volatility is a meaningless number. The test measures how much oil, when held at 250°C, evaporates into a stream of cold air over the course of one hour.
The reality is that your oil (typically at 100°C) might be exposed to a stream of hot blow-by for 300 hours. How much oil exits the crankcase with blow-by in this situation?
The answer depends on a whole host of variables? Do you drive modestly (like me) or in a spirited fashion (everyone else on BITOG)? Do you live in a non-extreme climate (like me) or do you live in a country that sees extremes of hot and cold? Do your engine see significant fuel dilution (from low tension rings, or because it's TGDI, or because you live in a cold climate?). Is your engine nice a tight (because it's relatively new) or worn out and letting through a lot of blow-by? Do you have a typical OCI of 3k miles or 15k?
I once ran an 11%-ish Noack oil of my own making and lost 40% of it over 15,000 miles!
From what I recall it's also just an indicator of how robust the base oil is and I also just don't want excessive oil vapor running around my engine. With DI engines having severe problems with intake carbon build up, this can be a concern.
Originally Posted By: SonofJoe
In itself, the Noack volatility is a meaningless number. The test measures how much oil, when held at 250°C, evaporates into a stream of cold air over the course of one hour.
The reality is that your oil (typically at 100°C) might be exposed to a stream of hot blow-by for 300 hours. How much oil exits the crankcase with blow-by in this situation?
The answer depends on a whole host of variables? Do you drive modestly (like me) or in a spirited fashion (everyone else on BITOG)? Do you live in a non-extreme climate (like me) or do you live in a country that sees extremes of hot and cold? Do your engine see significant fuel dilution (from low tension rings, or because it's TGDI, or because you live in a cold climate?). Is your engine nice a tight (because it's relatively new) or worn out and letting through a lot of blow-by? Do you have a typical OCI of 3k miles or 15k?
I once ran an 11%-ish Noack oil of my own making and lost 40% of it over 15,000 miles!
I think you and I agree - there may be some engines where NOACK is a factor, but for most it's not. There's a lot of debate over whether an oil is 5%, 10% or 15%, but experience of most of us have is that regardless of which one is in the sump, your oil consumption is low enough that it isn't a concern. Or putting it the other way around, if you have a consumption problem, switching to a low-NOACK oil won't fix it.
I usually drive very conservatively, and if I drive conservatively in the 2015 Ford Explorer with the TiVCT V6, it burns no oil from one change to the next, and I'm running $2 a quart Chevron Supreme 5w20. On the other hand, if I drive conservatively in my 2016 GT350, it burns high-end synthetic oil at about a quart per 2000 miles. However, if I take the GT350 and roar around a racetrack all day, it has a big impact on oil consumption: it stops! I burn more oil getting groceries than I do flat-out at 130MPH. Go figure. Not only that, the amount of oil in the catch can doesn't seem to change much either, although my belief is that the catch-can contents is fine droplets entrained in the crankcase air, and not some vapour that distills off the oil in the sump.
In itself, the Noack volatility is a meaningless number. The test measures how much oil, when held at 250°C, evaporates into a stream of cold air over the course of one hour.
The reality is that your oil (typically at 100°C) might be exposed to a stream of hot blow-by for 300 hours. How much oil exits the crankcase with blow-by in this situation?
The answer depends on a whole host of variables? Do you drive modestly (like me) or in a spirited fashion (everyone else on BITOG)? Do you live in a non-extreme climate (like me) or do you live in a country that sees extremes of hot and cold? Do your engine see significant fuel dilution (from low tension rings, or because it's TGDI, or because you live in a cold climate?). Is your engine nice a tight (because it's relatively new) or worn out and letting through a lot of blow-by? Do you have a typical OCI of 3k miles or 15k?
I once ran an 11%-ish Noack oil of my own making and lost 40% of it over 15,000 miles!
I think you and I agree - there may be some engines where NOACK is a factor, but for most it's not. There's a lot of debate over whether an oil is 5%, 10% or 15%, but experience of most of us have is that regardless of which one is in the sump, your oil consumption is low enough that it isn't a concern. Or putting it the other way around, if you have a consumption problem, switching to a low-NOACK oil won't fix it.
I usually drive very conservatively, and if I drive conservatively in the 2015 Ford Explorer with the TiVCT V6, it burns no oil from one change to the next, and I'm running $2 a quart Chevron Supreme 5w20. On the other hand, if I drive conservatively in my 2016 GT350, it burns high-end synthetic oil at about a quart per 2000 miles. However, if I take the GT350 and roar around a racetrack all day, it has a big impact on oil consumption: it stops! I burn more oil getting groceries than I do flat-out at 130MPH. Go figure. Not only that, the amount of oil in the catch can doesn't seem to change much either, although my belief is that the catch-can contents is fine droplets entrained in the crankcase air, and not some vapour that distills off the oil in the sump.
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And 11% is where some of the better GII+ 15w40 HDEO products land … and if a bit of “topping off” is a way of life in commercial applications … engines go steady state and run for hundreds of thousands of miles in lots of places …
Just 20 years ago (API SH), NOACK was allowed to be 25%
I think it's because big companies are evil, and sneaky.........
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
Now you're onto something! The lower the NOACK, the lesser the likelihood of forming varnish.
By the way, "low NOACK" is a fancy way of saying the oil doesn't dry out so fast.
I figure the lower the NOAK the lower the deposit potential.
Now you're onto something! The lower the NOACK, the lesser the likelihood of forming varnish.
By the way, "low NOACK" is a fancy way of saying the oil doesn't dry out so fast.
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
So it is the re-deposited vapors that form varnish? I thought it was oxidized oil.
I figure the lower the NOAK the lower the deposit potential.
So it is the re-deposited vapors that form varnish? I thought it was oxidized oil.
Originally Posted By: kschachn
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
So it is the re-deposited vapors that form varnish? I thought it was oxidized oil.
and fuel....plus it seems a reasonable hypothesis that there'll be more oxidation in the vapour phase, it being where the air is.
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
So it is the re-deposited vapors that form varnish? I thought it was oxidized oil.
and fuel....plus it seems a reasonable hypothesis that there'll be more oxidation in the vapour phase, it being where the air is.
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Originally Posted By: jaj
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
With an engine that has known intake valve deposit problem, I'd want as little evaporation as possible.
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
With an engine that has known intake valve deposit problem, I'd want as little evaporation as possible.
Originally Posted By: PandaBear
Originally Posted By: jaj
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
With an engine that has known intake valve deposit problem, I'd want as little evaporation as possible.
Maybe I missed out on this one, but isn't that due to the fuel rather than the oil?
Originally Posted By: jaj
I still can't figure out the fuss over NOACK. If 10% or more of your oil "distilled" away, everybody would be topping up relentlessly. Instead, most of us don't have to bother from one change to another, regardless of which oil we choose. My belief is that for most of us, if not all of us, NOACK is a meaningless number.
With an engine that has known intake valve deposit problem, I'd want as little evaporation as possible.
Maybe I missed out on this one, but isn't that due to the fuel rather than the oil?
I imagine the carbon deposits in the intake are actually primarily from dirty burning fuel... but once those deposits start forming on the metal, it's probably a lot easier for oil vapor to start sweating on to it and exacerbating the problem.
I believe the lowest NOACK oils at Walmart is a Valvoline 10w30, something like 6.5%. In the 0w40 range, I believe Castrol 0w40 is the only known one that is pretty low at 9%. I never see Pennzoil Ultra Pure premium whatever on the shelves at Walmart. Who knows what the NOACK is on the latest formulations of M1 0w40.
I believe the lowest NOACK oils at Walmart is a Valvoline 10w30, something like 6.5%. In the 0w40 range, I believe Castrol 0w40 is the only known one that is pretty low at 9%. I never see Pennzoil Ultra Pure premium whatever on the shelves at Walmart. Who knows what the NOACK is on the latest formulations of M1 0w40.
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Originally Posted By: Merkava_4
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
Now you're onto something! The lower the NOACK, the lesser the likelihood of forming varnish.
By the way, "low NOACK" is a fancy way of saying the oil doesn't dry out so fast.
Recently put a 10W30 with a 4.1 % noack number in a direct injected engine for potentially lower deposits over time.Will see how it plays out down the road.
Its been a while since I saw the numbers,but,Mobil 1 EP 5W30 was in the 9-10% range. I saw that in a test and was confirmed from a tech at Mobil.Was shocked he actually told me.
Originally Posted By: FZ1
I figure the lower the NOAK the lower the deposit potential.
Now you're onto something! The lower the NOACK, the lesser the likelihood of forming varnish.
By the way, "low NOACK" is a fancy way of saying the oil doesn't dry out so fast.
Recently put a 10W30 with a 4.1 % noack number in a direct injected engine for potentially lower deposits over time.Will see how it plays out down the road.
Its been a while since I saw the numbers,but,Mobil 1 EP 5W30 was in the 9-10% range. I saw that in a test and was confirmed from a tech at Mobil.Was shocked he actually told me.
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