^^^ All your "explanation" doesn't discount that fact that wear is for the most part not viscosity dependent unless the bottom end of the viscosity scale is reached (~2.2 cP as pointed out in these papers). And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
Rubbish advice on BITOG these days...
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Originally Posted By: ZeeOSix
^^^ All your "explanation" doesn't discount that fact that wear is for the most part not viscosity dependent unless the bottom end of the viscosity scale is reached (~2.2 cP as pointed out in these papers). And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
Hydrodynamic used to be known as "zero wear" operation for journal bearings, as clearly the surfaces don't touch...minimum oil film thickness in that regime IS dependent on viscosity, as I've shown you before. Provide your minimum oil film thickness is greater than the largest likely particle then the "zero wear" concept is maintained...for hydrodynamic lubrication. drop the viscosity/film thickness to the size of the largest particle, and wear commences, regardless of additives.
Boundary/mixed ISN'T zero wear, it's rate is controlled by additives...just like the papers say for boundary lubricated components in an engine.
Start-stop on engines there is boundary even in the bearings...they need tribofilms and additives.
OEMs are designing engines to reduce friction (note, not wear, friction and wear aren't the same thing), and are moving even bearings towards greater boundary/mixed, and therefore dependence on chemical interactions TO CONTROL wear, not eliminate.
^^^ All your "explanation" doesn't discount that fact that wear is for the most part not viscosity dependent unless the bottom end of the viscosity scale is reached (~2.2 cP as pointed out in these papers). And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
Hydrodynamic used to be known as "zero wear" operation for journal bearings, as clearly the surfaces don't touch...minimum oil film thickness in that regime IS dependent on viscosity, as I've shown you before. Provide your minimum oil film thickness is greater than the largest likely particle then the "zero wear" concept is maintained...for hydrodynamic lubrication. drop the viscosity/film thickness to the size of the largest particle, and wear commences, regardless of additives.
Boundary/mixed ISN'T zero wear, it's rate is controlled by additives...just like the papers say for boundary lubricated components in an engine.
Start-stop on engines there is boundary even in the bearings...they need tribofilms and additives.
OEMs are designing engines to reduce friction (note, not wear, friction and wear aren't the same thing), and are moving even bearings towards greater boundary/mixed, and therefore dependence on chemical interactions TO CONTROL wear, not eliminate.
Originally Posted By: ZeeOSix
And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
That's a gnats nut away from a contradiction in terms, yet I THINK it isn't quite one.
Doesn't mean it isn't absolute bollocks though.
And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
That's a gnats nut away from a contradiction in terms, yet I THINK it isn't quite one.
Doesn't mean it isn't absolute bollocks though.
Originally Posted By: Ducked
Originally Posted By: ZeeOSix
And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
That's a gnats nut away from a contradiction in terms, yet I THINK it isn't quite one.
Doesn't mean it isn't absolute bollocks though.
Maybe I should have qualified the statement with "in proper full hydrodynamic lubrication" - if the journal bearing is properly lubricated there will theoretically be zero wear because there is zero contact of surfaces. But in any lubricated system if the oil gets below the minimum "safe" viscosity it's going to cause more wear - that's the basic take away from the discussions.
And yes, journal bearings certainly are sensitive to viscosity when it falls below that safe point. A journal bearing's MOFT will keep decreasing as the viscosity decreases due to heat until metal-to-metal contact occurs. As Shannow said, that's all been hashed out quite extensively and seems everyone is on the same page there. If someone is going to race an engine that gets the oil temps way up (like 275 F or higher), then they better use a thicker oil so when it thins down from the heat it doesn't damage/wear the journal bearings, and also maybe cause extra wear to other components of the engine at the same time. Ring wear looks pretty sensitive to viscosity decrease when it gets below the 2.2-2.4 cP region.
Like shown above, the consensus seems to say that an oil viscosity below 2.2-2.4 cP is going to start causing increased wear on almost any engine part. Above that viscosity point, the wear rate is way down and basically constant no matter how much the viscosity increases. I would suspect that the MOFT in journal bearings would also be in extreme danger with the viscosity at 2.2-2.4 cP or below.
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
Originally Posted By: ZeeOSix
And wear in full hydrodynamic lubrication in journal bearings is even farther removed from the viscosity factor.
That's a gnats nut away from a contradiction in terms, yet I THINK it isn't quite one.
Doesn't mean it isn't absolute bollocks though.
Maybe I should have qualified the statement with "in proper full hydrodynamic lubrication" - if the journal bearing is properly lubricated there will theoretically be zero wear because there is zero contact of surfaces. But in any lubricated system if the oil gets below the minimum "safe" viscosity it's going to cause more wear - that's the basic take away from the discussions.
And yes, journal bearings certainly are sensitive to viscosity when it falls below that safe point. A journal bearing's MOFT will keep decreasing as the viscosity decreases due to heat until metal-to-metal contact occurs. As Shannow said, that's all been hashed out quite extensively and seems everyone is on the same page there. If someone is going to race an engine that gets the oil temps way up (like 275 F or higher), then they better use a thicker oil so when it thins down from the heat it doesn't damage/wear the journal bearings, and also maybe cause extra wear to other components of the engine at the same time. Ring wear looks pretty sensitive to viscosity decrease when it gets below the 2.2-2.4 cP region.
Like shown above, the consensus seems to say that an oil viscosity below 2.2-2.4 cP is going to start causing increased wear on almost any engine part. Above that viscosity point, the wear rate is way down and basically constant no matter how much the viscosity increases. I would suspect that the MOFT in journal bearings would also be in extreme danger with the viscosity at 2.2-2.4 cP or below.
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
Originally Posted By: ZeeOSix
Originally Posted By: ZeeOSix
Of course if you keep reducing the viscosity, at some point no matter what the AW package is the wear protection is going to suffer. That's what some of the SAE papers also address. Maybe better wear packages in the future will allow even thinner oils than what we see today.
To show an example, from: http://papers.sae.org/2013-01-0331/
Graph showing wear vs viscosity for various engine components. All but the con-rod bearings didn't show much if any change in the wear rate as long as the viscosity was above 2.2 cP. I also saw that mentioned in a few other papers discussing wear vs viscosity.
Does that apply to your engine, or my engine? There are other factors that influence the film thickness, besides viscosity, like sliding speed. And then there are others that dictate a thicker film needed, like increased surface roughness. and then there's the engine temperature.
I take away from the paper that above a certain film thicknes, going higher doesn't improve wear anymore. But I don't accept that this is for all engines, at all speeds, at all loads/conditions at 2.2-2.4 cP.
Originally Posted By: ZeeOSix
Of course if you keep reducing the viscosity, at some point no matter what the AW package is the wear protection is going to suffer. That's what some of the SAE papers also address. Maybe better wear packages in the future will allow even thinner oils than what we see today.
To show an example, from: http://papers.sae.org/2013-01-0331/
Graph showing wear vs viscosity for various engine components. All but the con-rod bearings didn't show much if any change in the wear rate as long as the viscosity was above 2.2 cP. I also saw that mentioned in a few other papers discussing wear vs viscosity.
Does that apply to your engine, or my engine? There are other factors that influence the film thickness, besides viscosity, like sliding speed. And then there are others that dictate a thicker film needed, like increased surface roughness. and then there's the engine temperature.
I take away from the paper that above a certain film thicknes, going higher doesn't improve wear anymore. But I don't accept that this is for all engines, at all speeds, at all loads/conditions at 2.2-2.4 cP.
I'm not saying 2.2~2.4 cP is the gospel standard for defining the minimum viscosity to prevent higher wear for every engine and every engine component - but it's info that's been discovered in pretty controlled test procedures in actual engines which is way more than anyone here could ever produce. Based on two different SAE papers that basically gave the same minimum viscosity point showing where increased wear started for many engine components, I think it's something worth noting.
In the table I posted earlier, it showed 0W-20 oil at 300 deg F has a viscosity of 2.6 cP which is basically the start of the increased wear zone. If I was using 5W-20 in a car at the track all day long and saw 280~300 F oil temps, I'd be pretty nervous about causing extra wear and possible engine damage. But if running 15W-50 at 300 F (3.7 cP) at the track I'd feel a lot more comfortable knowing I was a lot farther away from the increased wear zone. That makes sense to me. People can read all the info discussed and decide for themselves.
In the table I posted earlier, it showed 0W-20 oil at 300 deg F has a viscosity of 2.6 cP which is basically the start of the increased wear zone. If I was using 5W-20 in a car at the track all day long and saw 280~300 F oil temps, I'd be pretty nervous about causing extra wear and possible engine damage. But if running 15W-50 at 300 F (3.7 cP) at the track I'd feel a lot more comfortable knowing I was a lot farther away from the increased wear zone. That makes sense to me. People can read all the info discussed and decide for themselves.
The issue with relying on the additives to control wear is that they are depleatable. Use them more often, and they deplete faster. But how can you tell that is happening? Viscosity doen't deplete as long as the VI don't permanently shear and you don't get fuel dilution. but they do, of course, so where should you start? With a 2.6 cP xw-20 you're getting close to the limit that can be anywhere from 1.8 to 2.4 cP or your particular engine, or higher if it's an older design.
I scanned over the preview of the paper you posted last ( http://papers.sae.org/2013-01-0331/ ), and it seemed like especially high rpm (for a OTR truck) was damaging using low viscosity oils, My car is also a diesel but sees 4000+ rpm daily. I choose to sit a bit higher for starting viscosity, specifically around 3.5 cP (coincidentally about the same viscosity as the baseline oil in the paper). For a gas engine, 4000 rpm is nothing...
I scanned over the preview of the paper you posted last ( http://papers.sae.org/2013-01-0331/ ), and it seemed like especially high rpm (for a OTR truck) was damaging using low viscosity oils, My car is also a diesel but sees 4000+ rpm daily. I choose to sit a bit higher for starting viscosity, specifically around 3.5 cP (coincidentally about the same viscosity as the baseline oil in the paper). For a gas engine, 4000 rpm is nothing...
Originally Posted By: ZeeOSix
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
Bwahahahaha...that table is the J300 viscosity chart, and you just found it ???
And you link it to your newly found "consensus"...
(LOLing that you already flubbed the Cp/Cst conversion in another thread).
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
Bwahahahaha...that table is the J300 viscosity chart, and you just found it ???
And you link it to your newly found "consensus"...
(LOLing that you already flubbed the Cp/Cst conversion in another thread).
Originally Posted By: ZeeOSix
^^^ So what? Guess I need to keep bringing up all the stuff you've "flubbed up". You should really drop the childish behavior, it's really not very becoming.
I'm sorry ZeeOSix, but as you say in all these discussions, we ultimately, regardless of our secret agent status learn something.
...and J300 has been around for a while...and that version is a few versions obsolete.
I came across the 1923 version of the table
It doesn't help your viscosity free argument either...It DOES explain where we get our bottle grades 'though, don't you think ?
^^^ So what? Guess I need to keep bringing up all the stuff you've "flubbed up". You should really drop the childish behavior, it's really not very becoming.
I'm sorry ZeeOSix, but as you say in all these discussions, we ultimately, regardless of our secret agent status learn something.
...and J300 has been around for a while...and that version is a few versions obsolete.
I came across the 1923 version of the table
It doesn't help your viscosity free argument either...It DOES explain where we get our bottle grades 'though, don't you think ?
OVERKILL
$100 Site Donor 2021
Originally Posted By: ZeeOSix
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
That's the J300 table (as Shannow noted) which shows the minimums for the various grades. Ergo, it necessitates actually knowing the viscometric characteristics of the lubricant you are working with, as there can be some significant differences. This is a requirement in order to properly form any sort plan that involves deviating in viscosity from the factory recommendation. Also, that's an old copy, the limits for 10w-40, 5w-40 and 0w-40 have been bumped up to 3.5 now.
As an example, the new Mobil 1 Annual Protection product, both the 5w-20 and 0w-20 have an HTHS in-line with the minimum range, hitting at 2.6mPa. However the EP 0w-20 has an HTHS of 2.7, and the 5w-20 has one of 2.75. Mobil 1 HM 5w-20 is 2.7, AFE 0w-20 is 2.7, and Mobil 1 5w-20 is 2.75. This demonstrates some of the variability of oils, even from the same manufacturer, within the xW-20 range.
Mobil 1 FS 0w-40 has an HTHS of 3.6mPa, Delvac 1 5w-40 has one of 3.7, TDT 5w-40 has one of 3.8.
However, the biggest difference for regularly available PCMO's is when comparing an ILSAC product to an ACEA one:
AFE 0w-30, HTHS of 3.0mPa
ESP 0w-30, HTHS of 3.5mPa
Here's a table I found that shows SAE motor oil viscosity at 150 deg C (302 F), and the corresponding viscosity in centipoise (mPa.s). Shows that 20 weight is at 2.6 cP. I'd say that's borderline, and I certainly wouldn't run a xW-20 in any track car unless it has some insane oil coolers that keep the max oil temperature below 240 F. You'd want something like xW-40 or xW-50 for sure.
That's the J300 table (as Shannow noted) which shows the minimums for the various grades. Ergo, it necessitates actually knowing the viscometric characteristics of the lubricant you are working with, as there can be some significant differences. This is a requirement in order to properly form any sort plan that involves deviating in viscosity from the factory recommendation. Also, that's an old copy, the limits for 10w-40, 5w-40 and 0w-40 have been bumped up to 3.5 now.
As an example, the new Mobil 1 Annual Protection product, both the 5w-20 and 0w-20 have an HTHS in-line with the minimum range, hitting at 2.6mPa. However the EP 0w-20 has an HTHS of 2.7, and the 5w-20 has one of 2.75. Mobil 1 HM 5w-20 is 2.7, AFE 0w-20 is 2.7, and Mobil 1 5w-20 is 2.75. This demonstrates some of the variability of oils, even from the same manufacturer, within the xW-20 range.
Mobil 1 FS 0w-40 has an HTHS of 3.6mPa, Delvac 1 5w-40 has one of 3.7, TDT 5w-40 has one of 3.8.
However, the biggest difference for regularly available PCMO's is when comparing an ILSAC product to an ACEA one:
AFE 0w-30, HTHS of 3.0mPa
ESP 0w-30, HTHS of 3.5mPa
Originally Posted By: Ducked
Originally Posted By: alarmguy
T...
Originally Posted By: alarmguy
T...
alarmguy said:I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.
Also disagree about mag drain plugs, though I have one. They do not have "limitless capacity". They have very limited capacity, though they have no lower limit on ferrous particle size trapped. If you want significant capacity you probably have to go for a bandolier round the oil filter, though I'm not sure that magnetised wear particles are necessarily a good thing in an engine.
The automotive world does not agree with you. Many high end manufacturers use them in their vehicles, car, truck, motorcycle, boat.
Actually, we are almost on the same page since you do use one, but BITOG doesnt let you delete a full post.)
I just put this in there for others not into the subject.
Last edited:
Ok, who here drains their oil hot, then siphons or extracts the 1/2 qt of oil left in the pan?
Originally Posted By: Shannow
I came across the 1923 version of the table
It doesn't help your viscosity free argument either...It DOES explain where we get our bottle grades 'though, don't you think ?
Originally Posted By: OVERKILL
That's the J300 table which shows the minimums for the various grades. Ergo, it necessitates actually knowing the viscometric characteristics of the lubricant you are working with, as there can be some significant differences. This is a requirement in order to properly form any sort plan that involves deviating in viscosity from the factory recommendation. Also, that's an old copy, the limits for 10w-40, 5w-40 and 0w-40 have been bumped up to 3.5 now.
As an example, the new Mobil 1 Annual Protection product, both the 5w-20 and 0w-20 have an HTHS in-line with the minimum range, hitting at 2.6mPa. However the EP 0w-20 has an HTHS of 2.7, and the 5w-20 has one of 2.75. Mobil 1 HM 5w-20 is 2.7, AFE 0w-20 is 2.7, and Mobil 1 5w-20 is 2.75. This demonstrates some of the variability of oils, even from the same manufacturer, within the xW-20 range.
Mobil 1 FS 0w-40 has an HTHS of 3.6mPa, Delvac 1 5w-40 has one of 3.7, TDT 5w-40 has one of 3.8.
However, the biggest difference for regularly available PCMO's is when comparing an ILSAC product to an ACEA one:
AFE 0w-30, HTHS of 3.0mPa
ESP 0w-30, HTHS of 3.5mPa
Guys ... this is now become hair splitting. I wasn't claiming or arguing that the chart is the exact HTHS viscosity of every xW-20 thru xW-50 oil in the world. The chart was used to give a feel for the HTHS viscosity difference between the different weights of motor oils. Even though OVERKILL listed some current HTHS viscosities, they still aren't a huge jump better than the ones in the old chart.
Still doesn't change the fact that wear as a function of viscosity becomes much lower and pretty much holds constant above a certain HTHS viscosity threshold - that's the basis of this discussion. Based on the SAE papers, the threshold was defined around 2.2~2.4 cP at the time. One of those papers is dated 2013.
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow - had to lob at least one back at ya.
Now let's all stop that petty behavior.
I came across the 1923 version of the table
It doesn't help your viscosity free argument either...It DOES explain where we get our bottle grades 'though, don't you think ?
Originally Posted By: OVERKILL
That's the J300 table which shows the minimums for the various grades. Ergo, it necessitates actually knowing the viscometric characteristics of the lubricant you are working with, as there can be some significant differences. This is a requirement in order to properly form any sort plan that involves deviating in viscosity from the factory recommendation. Also, that's an old copy, the limits for 10w-40, 5w-40 and 0w-40 have been bumped up to 3.5 now.
As an example, the new Mobil 1 Annual Protection product, both the 5w-20 and 0w-20 have an HTHS in-line with the minimum range, hitting at 2.6mPa. However the EP 0w-20 has an HTHS of 2.7, and the 5w-20 has one of 2.75. Mobil 1 HM 5w-20 is 2.7, AFE 0w-20 is 2.7, and Mobil 1 5w-20 is 2.75. This demonstrates some of the variability of oils, even from the same manufacturer, within the xW-20 range.
Mobil 1 FS 0w-40 has an HTHS of 3.6mPa, Delvac 1 5w-40 has one of 3.7, TDT 5w-40 has one of 3.8.
However, the biggest difference for regularly available PCMO's is when comparing an ILSAC product to an ACEA one:
AFE 0w-30, HTHS of 3.0mPa
ESP 0w-30, HTHS of 3.5mPa
Guys ... this is now become hair splitting. I wasn't claiming or arguing that the chart is the exact HTHS viscosity of every xW-20 thru xW-50 oil in the world. The chart was used to give a feel for the HTHS viscosity difference between the different weights of motor oils. Even though OVERKILL listed some current HTHS viscosities, they still aren't a huge jump better than the ones in the old chart.
Still doesn't change the fact that wear as a function of viscosity becomes much lower and pretty much holds constant above a certain HTHS viscosity threshold - that's the basis of this discussion. Based on the SAE papers, the threshold was defined around 2.2~2.4 cP at the time. One of those papers is dated 2013.
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow - had to lob at least one back at ya.
Originally Posted By: alarmguy
Originally Posted By: Ducked
Originally Posted By: alarmguy
I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.
Also disagree about mag drain plugs, though I have one. They do not have "limitless capacity". They have very limited capacity, though they have no lower limit on ferrous particle size trapped. If you want significant capacity you probably have to go for a bandolier round the oil filter, though I'm not sure that magnetised wear particles are necessarily a good thing in an engine.
The automotive world does not agree with you. Many high end manufacturers use them in their vehicles, car, truck, motorcycle, boat.
Actually, we are almost on the same page since you do use one, but BITOG doesnt let you delete a full post.) I just put this in there for others not into the subject.
Having a magnetic drain plug is way better than not. And as alarmguy mentioned, a lot of new vehicles come with a magnetic drain plug these days. I prefer aftermarket because they seem to use much stronger magnets. Motorcycles have used them for decades.
During break-in of all the vehicles I've ever used a magnetic drain plug in, I've always seen a good amount of collected ferrous material. The amount of collected Fe material drops off noticeably after break-in is complete.
At 5K miles with a 4K OCI (put aftermarket mag plug in at 1K miles 1st oil change).
At 37K miles with a 5K OCI.
Originally Posted By: Ducked
Originally Posted By: alarmguy
I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.
Also disagree about mag drain plugs, though I have one. They do not have "limitless capacity". They have very limited capacity, though they have no lower limit on ferrous particle size trapped. If you want significant capacity you probably have to go for a bandolier round the oil filter, though I'm not sure that magnetised wear particles are necessarily a good thing in an engine.
The automotive world does not agree with you. Many high end manufacturers use them in their vehicles, car, truck, motorcycle, boat.
Actually, we are almost on the same page since you do use one, but BITOG doesnt let you delete a full post.
) I just put this in there for others not into the subject.Having a magnetic drain plug is way better than not. And as alarmguy mentioned, a lot of new vehicles come with a magnetic drain plug these days. I prefer aftermarket because they seem to use much stronger magnets. Motorcycles have used them for decades.
During break-in of all the vehicles I've ever used a magnetic drain plug in, I've always seen a good amount of collected ferrous material. The amount of collected Fe material drops off noticeably after break-in is complete.
At 5K miles with a 4K OCI (put aftermarket mag plug in at 1K miles 1st oil change).
At 37K miles with a 5K OCI.
Originally Posted By: ZeeOSix
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
It's SAE J300, the viscosity and HTHS ranges for the oil grades.
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/http://ew5b2btest.earlweb.com/files/engine_chart.pdf
http://standards.sae.org/j300_201304/
The 1923 table was to show that by not being in the remotest bit careful, you can grab a version that's (way) out of date...and if you'd been following along the (hundreds) of times that J300 gets discussed it wouldn't have been a "table I suddenly discovered". What's that got to do with "typical cherry picking"...it was a table, it was J300, and it was out of date...simply that.
And yes, HTHS a=was a relatively recent addition, after it was worked out that the kinematic viscosities of multigrades didn't offer the protection that their grades would otherwise suggest.
And I'm still struggling with how the table that you just discovered proves anything about your bearings being immune to viscosity down to 2.2 HTHS...why then do so many manufacturers spec HTHs of 3.5 minimum for their equipment ?
Are they wrong ?
Originally Posted By: ZeeOSix
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow - had to lob at least one back at ya.
Now let's all stop that petty behavior.
Yeah...look at a stationary engine with an accusump, and watch the oil flow...linear one dimensional thinking...and I've never said that pressure doesn't move more oi through the engine, NOR your claim that I was stating that the bearings would siphon oil up the intake tube without an oil pump.
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
It's SAE J300, the viscosity and HTHS ranges for the oil grades.
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/http://ew5b2btest.earlweb.com/files/engine_chart.pdf
http://standards.sae.org/j300_201304/
The 1923 table was to show that by not being in the remotest bit careful, you can grab a version that's (way) out of date...and if you'd been following along the (hundreds) of times that J300 gets discussed it wouldn't have been a "table I suddenly discovered". What's that got to do with "typical cherry picking"...it was a table, it was J300, and it was out of date...simply that.
And yes, HTHS a=was a relatively recent addition, after it was worked out that the kinematic viscosities of multigrades didn't offer the protection that their grades would otherwise suggest.
And I'm still struggling with how the table that you just discovered proves anything about your bearings being immune to viscosity down to 2.2 HTHS...why then do so many manufacturers spec HTHs of 3.5 minimum for their equipment ?
Are they wrong ?
Originally Posted By: ZeeOSix
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow - had to lob at least one back at ya.
Yeah...look at a stationary engine with an accusump, and watch the oil flow...linear one dimensional thinking...and I've never said that pressure doesn't move more oi through the engine, NOR your claim that I was stating that the bearings would siphon oil up the intake tube without an oil pump.
Originally Posted By: alarmguy
Originally Posted By: Ducked
Originally Posted By: alarmguy
T...
Originally Posted By: Ducked
Originally Posted By: alarmguy
T...
alarmguy said:I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.
Also disagree about mag drain plugs, though I have one. They do not have "limitless capacity". They have very limited capacity, though they have no lower limit on ferrous particle size trapped. If you want significant capacity you probably have to go for a bandolier round the oil filter, though I'm not sure that magnetised wear particles are necessarily a good thing in an engine.
The automotive world does not agree with you. Many high end manufacturers use them in their vehicles, car, truck, motorcycle, boat.
Actually, we are almost on the same page since you do use one, but BITOG doesnt let you delete a full post.
I just put this in there for others not into the subject.
OK. I said I'm not sure, and I'm not.
Though its probably the way to bet, automotive industry practice (which, as you note, varies) isn't necessarily a guide to best practice for an individual, since manufacturers aren't necessarily interested in maximising engine life. My impression of magnetic drain plugs is that they are primarily intended to be diagnostic chip-catchers, since they are too small to have much capacity.
A magnetic dipstick, which I also use, makes MUCH more sense in the diagnostic role, but I've never seen or heard of one on a car. (Is there a patent lawyer in the house?)
I've never seen any research on the effect of magnetised particles in the engine (anticipating an again-with-the "find an SAE paper" shtick) but I did find this:-
Not quite scientific research, but the only mention I've seen of this problem, if it is a problem.
Certainly I don't recall it being mentioned in any other discussion of magnetic "filtration".
http://www.machinerylubrication.com/Read/781/particle-contamination
"Magnetic Susceptibility. Permanent magnets are used in some filters and online wear particle sensors. Particles of iron or steel that are attracted to a magnetic field are preferentially separated from the oil by these devices. Later, any particles that may have sloughed off these separators and sensors (due to shock or surge flow conditions) are often left magnetized. They can then magnetically grip onto steel orifices, glands and oilways restricting flow or simply interfering with machine part movement.
Additionally, directional control and servo valves commonly used in hydraulic systems deploy the use of electro magnets in their solenoids. The actuation of these valves can be adversely affected by the magnetic susceptibility of iron and steel particles that are attracted by the solenoid."
Also part of an extended oily argument/discussion here
http://forumosa.com/taiwan/viewtopic.php?f=75&t=102604&hilit=magnetic+dipstick
Long ago on a website far, far away.
The fwd BMC cars had a magnetic sump plug...we used it as a diagnostic tool. If a tooth from the final drive gears was on there on a oil change, you might be doing a bigger job on the car at a later date.
Originally Posted By: Shannow
Originally Posted By: ZeeOSix
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
It's SAE J300, the viscosity and HTHS ranges for the oil grades.
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/http://ew5b2btest.earlweb.com/files/engine_chart.pdf
http://standards.sae.org/j300_201304/
The 1923 table was to show that by not being in the remotest bit careful, you can grab a version that's (way) out of date...and if you'd been following along the (hundreds) of times that J300 gets discussed it wouldn't have been a "table I suddenly discovered". What's that got to do with "typical cherry picking"...it was a table, it was J300, and it was out of date...simply that.
It might have been out of date, but the HTHS numbers for the oils it showed didn't really change much (raised 30 and lowered 0W-40 thru 10W-40 a bit). The big change was the addition of even thinner oils 8, 12 & 16.
Originally Posted By: Shannow
And yes, HTHS a=was a relatively recent addition, after it was worked out that the kinematic viscosities of multigrades didn't offer the protection that their grades would otherwise suggest.
And I'm still struggling with how the table that you just discovered proves anything about your bearings being immune to viscosity down to 2.2 HTHS...why then do so many manufacturers spec HTHs of 3.5 minimum for their equipment ?
Are they wrong ?
I wasn't claiming the journal bearings would be fine down to 2.2 HTHS ... like I said, I'd be really nervous running a car at the track with 5W-20 because of the typically low HTHS. The papers I reference didn't include journal bearings in their HTHS wear tests, so there was nothing to say what the bottom HTHS limit is for bearings, and it will vary some due to bearing design and operational conditions because hydrodynamic MOFT is involved.
I did dig around some looking for technical information on the relationship between HTHS viscosity and bearing MOFT, and also HTHS and wear in journal bearings. Since MOFT going to zero means bearing wear and damage, it seems someone would have correlated journal bearing wear to HTHS. Did find some older papers showing higher HTHS gave higher MOFT. Also found one paper that tested two different 0W-20 oils, one with HTHS of 2.8 cP and the other with a 0W-20 with 3.6 cP. Blurb from that one:
As outlined at the beginning of this section, the studied 0W20 lubricant is required to be extremely
shear stable with a HTHS-viscosity of 3.6 mPa s. Therefore, a more common 0W20 lubricant with
a HTHS-viscosity of 2.8 mPa s is investigated in addition. However, the analysis with the reduced
HTHS-viscosity lubricant showed a strong presence of metal-metal contact under full load operation
already at 1000 rpm engine speed. As the inertia forces increase with increasing engine speed,
the amount of metal-metal contact will be even more severe for higher engine speeds. As a consequence,
it is concluded that for the present engine construction a HTHS-viscosity of 3.6 mPa s represents an
optimum value at least for the journal bearings. A further HTHS-viscosity reduction is expected to
require additional efforts to maintain the high service life that is obtained with lubricants having a
HTHS-viscosity of 3.6 mPa s.
Here's a different paper that talks about new types of bearing surface materials and surface texturing to help the bearings survive with the use of ever thinning motor oils. Journal bearing lubrication is getting more complex as these new oils are coming into play. https://www.intechopen.com/books/advance...vere-conditions
Originally Posted By: Shannow
Originally Posted By: ZeeOSix
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow ...
Yeah...look at a stationary engine with an accusump, and watch the oil flow...linear one dimensional thinking...and I've never said that pressure doesn't move more oi through the engine, NOR your claim that I was stating that the bearings would siphon oil up the intake tube without an oil pump.
Guess you want to continue hashing this stuff. You know Shannow, I'd rather get along with you than not, as we've both opened each others eyes in some of these discussions. Nobody here is an expert on every subject ever discussed.
The accusump example was to try and get you to realize that oil pressure causes oil flow through the bearings regardless if they are stationary or rotating because there's a clearance involved. Pressure delta put across a flow path equals flow. And as said quite a few times, the comment I made about the bearings sucking oil w/o a pump was total sarcasm since you were so locked into the bearing flow only as function of drawing/sucking from the galleries due to the hydrodynamic flow side of the picture. I guess it didn't work very well because after all our back and forth (and actually agreeing at one point) you still were making statements which clearly indicated you are only seeing the Qh factor (hydrodynamic flow) and not the total picture with includes the Qp factor (supply pressure flow). Total bearing side leakage = Qs = Qh + Qp.
Originally Posted By: ZeeOSix
OK, so what's the latest ASTM test standard for HTHS viscosity ratings, and where's the chart? The chart I showed references ASTM D4683, D4741 and DS481.
The 1923 table has nothing to do with HTHS viscosity. Typical cherry picking of irrelevant information to twist up the real discussion.
It's SAE J300, the viscosity and HTHS ranges for the oil grades.
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/http://ew5b2btest.earlweb.com/files/engine_chart.pdf
http://standards.sae.org/j300_201304/
The 1923 table was to show that by not being in the remotest bit careful, you can grab a version that's (way) out of date...and if you'd been following along the (hundreds) of times that J300 gets discussed it wouldn't have been a "table I suddenly discovered". What's that got to do with "typical cherry picking"...it was a table, it was J300, and it was out of date...simply that.
It might have been out of date, but the HTHS numbers for the oils it showed didn't really change much (raised 30 and lowered 0W-40 thru 10W-40 a bit). The big change was the addition of even thinner oils 8, 12 & 16.
Originally Posted By: Shannow
And yes, HTHS a=was a relatively recent addition, after it was worked out that the kinematic viscosities of multigrades didn't offer the protection that their grades would otherwise suggest.
And I'm still struggling with how the table that you just discovered proves anything about your bearings being immune to viscosity down to 2.2 HTHS...why then do so many manufacturers spec HTHs of 3.5 minimum for their equipment ?
Are they wrong ?
I wasn't claiming the journal bearings would be fine down to 2.2 HTHS ... like I said, I'd be really nervous running a car at the track with 5W-20 because of the typically low HTHS. The papers I reference didn't include journal bearings in their HTHS wear tests, so there was nothing to say what the bottom HTHS limit is for bearings, and it will vary some due to bearing design and operational conditions because hydrodynamic MOFT is involved.
I did dig around some looking for technical information on the relationship between HTHS viscosity and bearing MOFT, and also HTHS and wear in journal bearings. Since MOFT going to zero means bearing wear and damage, it seems someone would have correlated journal bearing wear to HTHS. Did find some older papers showing higher HTHS gave higher MOFT. Also found one paper that tested two different 0W-20 oils, one with HTHS of 2.8 cP and the other with a 0W-20 with 3.6 cP. Blurb from that one:
As outlined at the beginning of this section, the studied 0W20 lubricant is required to be extremely
shear stable with a HTHS-viscosity of 3.6 mPa s. Therefore, a more common 0W20 lubricant with
a HTHS-viscosity of 2.8 mPa s is investigated in addition. However, the analysis with the reduced
HTHS-viscosity lubricant showed a strong presence of metal-metal contact under full load operation
already at 1000 rpm engine speed. As the inertia forces increase with increasing engine speed,
the amount of metal-metal contact will be even more severe for higher engine speeds. As a consequence,
it is concluded that for the present engine construction a HTHS-viscosity of 3.6 mPa s represents an
optimum value at least for the journal bearings. A further HTHS-viscosity reduction is expected to
require additional efforts to maintain the high service life that is obtained with lubricants having a
HTHS-viscosity of 3.6 mPa s.
Here's a different paper that talks about new types of bearing surface materials and surface texturing to help the bearings survive with the use of ever thinning motor oils. Journal bearing lubrication is getting more complex as these new oils are coming into play. https://www.intechopen.com/books/advance...vere-conditions
Originally Posted By: Shannow
Originally Posted By: ZeeOSix
And at least some secret agent schools covered the supply pressure factor of journal bearing oil flow ...
Yeah...look at a stationary engine with an accusump, and watch the oil flow...linear one dimensional thinking...and I've never said that pressure doesn't move more oi through the engine, NOR your claim that I was stating that the bearings would siphon oil up the intake tube without an oil pump.
Guess you want to continue hashing this stuff. You know Shannow, I'd rather get along with you than not, as we've both opened each others eyes in some of these discussions. Nobody here is an expert on every subject ever discussed.
The accusump example was to try and get you to realize that oil pressure causes oil flow through the bearings regardless if they are stationary or rotating because there's a clearance involved. Pressure delta put across a flow path equals flow. And as said quite a few times, the comment I made about the bearings sucking oil w/o a pump was total sarcasm since you were so locked into the bearing flow only as function of drawing/sucking from the galleries due to the hydrodynamic flow side of the picture. I guess it didn't work very well because after all our back and forth (and actually agreeing at one point) you still were making statements which clearly indicated you are only seeing the Qh factor (hydrodynamic flow) and not the total picture with includes the Qp factor (supply pressure flow). Total bearing side leakage = Qs = Qh + Qp.
And as I'd explained to you, I've been changing the bearing characteristics on the turbines for a decade, changing radial clearance to increase flow and have a lower stable operating temperature, changing temperature of the entire lube supply to take some instability out of a generator bearing...Changing supply pressures to achieve the same thing, and ultimately CHANGING THE ORIFICE sizing in that very bearing to reduce the flow, increase the operating temperature and get all the others back to design.
I understood pressure and flow, taking it as akin to you asking for an SAE paper on oil floating on water.
I disagreed that the engine designers, en masse, were intentionally relying on jamming excess oil through the bearings to keep them cool.
In an IC engine, the supply pressure is there to ensure that the worst bearing receives adequate volume of oil...
I understood pressure and flow, taking it as akin to you asking for an SAE paper on oil floating on water.
I disagreed that the engine designers, en masse, were intentionally relying on jamming excess oil through the bearings to keep them cool.
In an IC engine, the supply pressure is there to ensure that the worst bearing receives adequate volume of oil...
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