Revisiting Oil differences (all in the spirit of fighting #2/6 bearing failure)
05-07-2007, 02:16 AM
#16
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Thread Starter
I guess everyone is missing my point. its a clear indication that the thermal breakdown is quite a bit worse with mobil 1. when i was in my old 79 with mobil 1, the oil pressure light started to come on. during practice and to and from the track, it was on the low side, but i thought that was just a difference in cars (vs my S4 and part euro 5 liter and 4.7 racer) it was sufficient. however, in race conditions, (conditions most have found to be ripe for blowing engines), the oil could be breaking down to the point that it is not in a condtion to protect some marginal areas (such as our #2-6 bearings), thus increasing the risk for failure.
the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!
MK
the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!
MK
Originally Posted by Bill Ball
I'm not sure I understand what the problem is. 4 bars at 2000 RPM is plenty. When you guys are racing along at high RPM, both oils would be 5 bars. Regardless, 4 bars will circulate the oil just fine. That's 60 PSI at 2000 RPM.
I've never had a problem with low oil pressure with 15W 50 M1. I did have a problem with low oil pressure at idle after running the car at near redzone coolant temps when opern road racing when I used some 10W 40 Castrol Syntec. So, I went back the M1 15W 50.
I've never had a problem with low oil pressure with 15W 50 M1. I did have a problem with low oil pressure at idle after running the car at near redzone coolant temps when opern road racing when I used some 10W 40 Castrol Syntec. So, I went back the M1 15W 50.
05-07-2007, 03:28 AM
#17
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Mark:
Like I said, if the Amzoil is thicker at temperature, you will get more oil pressure.
Sounds like you might do good spending some time reducing the oil temperature. The engines make more power when the are cooler....and last longer.....which doesn't seem to be a problem for you, but poor Scott probably wouldn't mind not having the "motor de jour".
gb
Like I said, if the Amzoil is thicker at temperature, you will get more oil pressure.
Sounds like you might do good spending some time reducing the oil temperature. The engines make more power when the are cooler....and last longer.....which doesn't seem to be a problem for you, but poor Scott probably wouldn't mind not having the "motor de jour".
gb
05-07-2007, 07:17 AM
#18
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Originally Posted by GregBBRD
The second issue the 928 engine has is getting the oil to return to the sump. If a particular oil has less foaming characteristics, it will return better and therefore the sump will have more oil in it with less foam. (Note that less foam also makes more oil pressure, too.) If Amzoil has the tendency to foam less than another oil, this would help, also.
gb
Were it not for the ability of the 928 engine to try and emulate a front loading washing machine loaded with hand wash detergent, I bet any decent oil would do the trick. Mark K to my mind empirically or otherwise seems to have "proven" that Amsoil does seem to help prevent the oil pressure reduction associated with oil foaming that would seem to be a significant contributory cause of 2/6 bearing failure on stock 928 engines.
It would be interesting to know if there is out there a 928 engine that is tracked that is "drilled like a chevy" (or whatever the crank modification is that helps reduce oil starvation to the 2/6 bearing) but has no other modifications from stock ie no accusump and no changes to the oil pan baffles etc. And if there is did it still suffer 2/6 failure until the oil was changed to Amsoil ?
05-08-2007, 03:15 AM
#19
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Hi,
Mark - Back to rubbishing Mobil again? Its sure been your pattern for some years now!
Isn't it generally accepted that OIL STARVATION is the MOST LIKELY cause of the failures in the 2/6 bearing area??
Gauge INDICATED oil pressure has VERY LITTLE to do with the OPERATING OIL PRESSURE within a Journal bearing as they typically run at many hundreds of PSI and way beyond what you see on your gauge!! What is extremely important is FLOW!! Both for supply and cooling purposes - oil pressure just indicates the restriction to flow
The three oils you mention all have differing HTHS viscosities (@ 150C) so a variance will be evident -and as much as 10%. They are all way above Porsche's prescribed minimum of 3.5cSt and this is the "film strength" you perhaps allude to
As both the "other" oils have not submitted their products for ACEA testing we know very little about their oxidation and extended viscosity/shear relationships. We also do not know the levels of the silaxanes and silicone, organic copolymers that control foaming and how durable they really are
And Mark the "shearing" performance is very important indeed
But then we have covered all this before on here haven't we!
Porsche never saw it necessary to issue a TSB saying that 4bar at 2000rpm was not enough OP - even the Driver's Handbook says to expect the oil light to flicker or come on at a very hot idle!!!!
You said: "the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!"
Mark, the Used Oil Analysis (UOA) of your own oil was only an "average" result - no better and in some cases worse than the many others I now store on 928s that use a variety of oils!
A number probably would have done the same or even a better job!
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
Mark, one tends to suspect you "sell" Amsoil!!! I DON'T sell Mobil or any other product!!!
Keep using Amsoil Mark it suits your purpose well and they are good products too but it would seem much more professional not to constantly "knock" what others use with great success throughout the World.
And I DON'T use Mobil 1 in my 928!!!!
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
Mark - Back to rubbishing Mobil again? Its sure been your pattern for some years now!
Isn't it generally accepted that OIL STARVATION is the MOST LIKELY cause of the failures in the 2/6 bearing area??
Gauge INDICATED oil pressure has VERY LITTLE to do with the OPERATING OIL PRESSURE within a Journal bearing as they typically run at many hundreds of PSI and way beyond what you see on your gauge!! What is extremely important is FLOW!! Both for supply and cooling purposes - oil pressure just indicates the restriction to flow
The three oils you mention all have differing HTHS viscosities (@ 150C) so a variance will be evident -and as much as 10%. They are all way above Porsche's prescribed minimum of 3.5cSt and this is the "film strength" you perhaps allude to
As both the "other" oils have not submitted their products for ACEA testing we know very little about their oxidation and extended viscosity/shear relationships. We also do not know the levels of the silaxanes and silicone, organic copolymers that control foaming and how durable they really are
And Mark the "shearing" performance is very important indeed
But then we have covered all this before on here haven't we!
Porsche never saw it necessary to issue a TSB saying that 4bar at 2000rpm was not enough OP - even the Driver's Handbook says to expect the oil light to flicker or come on at a very hot idle!!!!
You said: "the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!"
Mark, the Used Oil Analysis (UOA) of your own oil was only an "average" result - no better and in some cases worse than the many others I now store on 928s that use a variety of oils!
A number probably would have done the same or even a better job!
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
Mark, one tends to suspect you "sell" Amsoil!!! I DON'T sell Mobil or any other product!!!
Keep using Amsoil Mark it suits your purpose well and they are good products too but it would seem much more professional not to constantly "knock" what others use with great success throughout the World.
And I DON'T use Mobil 1 in my 928!!!!
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
05-08-2007, 11:07 AM
#20
Rennlist Member
Originally Posted by Doug Hillary
Hi,
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
Let's get something straight - Castrol RS 10W60 is not a fully synthetic oil. It is in fact made from base mineral oil with high quality synthetic additives. MOTUL Le Mans on the other hand is a true synthetic oil - i.e. created by boffins in white lab coats, which "built" it from scratch in a lab.
I used Mobil 1 Motorsport 15w50 in my heavily tracked GT and it was OK. Usage was acceptable and oil pressure was good. Then I switched to Motul Le Mans 15w50 and have never looked back - no burning, oil pressure consistently higher through the temp range and better resistance to fuel dilution...
Alex
1990 928GT-R (race car) Motul Le Mans 15W50
1984 928 S2 5spd Castrol GTX Magnatec 10W40
2006 BMW Z4M Coupe Castrol RS 10W60
05-08-2007, 01:21 PM
#21
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Thread Starter
Doug, i call them how i see them!
you keep on bringing up oil analysis, and say that amzoil is the same as other oils. remember, thats not the point. why dont you do or find some analysis of all those oils at 280F and get back to me? I would suspect you would find the differnces im alluding to, there.
you again bring up an "approved porsche list" into the discussion. have you ever worked or partnered with a german company before? believe me those lists are strictly business agreements, and have nothing do do with performance. the fact that the manual suggests that the oil pressure light coming on is ok, is more the reason to beware. in most cases, im sure this is not an issue, especially at idle. however, it could be a cover-up for a known issue with the choice of the "partnered preferred" oil, so their shops dont get buried with concerned customers in texas in the summer time.
You and i both know, most oil is find for general purpose, but the fact that i have been racing for so long with none of the issues of the 10 or so blown engines using mobil 1 at the track, should not be totally discounted or ignored. sure, ill admit, there is a little bit of brand loyalty on my part due to what i have read and seen, as well as experienced. Not too many 928 racers have as much time on an original engine as i do. the fact that it has lasted so long, against all odds, is something to take note of. (ie no oil cooler, no accusump, and running times that rival any of the top Grand Am Cup GS racers in the world)
Its not so much the fact that the oil pressure isnt sufficient at 4 bar, but the indication that some thermal breakdown is occuring and that that maybe an indication that the oils protective qualities are going down at the higher temps.
at the bearing, if the oil is marginally protectiing due to high temp, that could be an issue. It is "generally " accepted that oil starvation is the cause, but that is also a theory. It is just as likely that it could be caused by themal breakdown of the oil or som eother related cause. folks have lost motors that have accusumps, drilled cranks, but the most common denominator has been Mobil 1. Since none of us work for the oil companies, and that includes me, i pick the things others have used to be successful with. at least, its cheap insurance.
mk
you keep on bringing up oil analysis, and say that amzoil is the same as other oils. remember, thats not the point. why dont you do or find some analysis of all those oils at 280F and get back to me? I would suspect you would find the differnces im alluding to, there.
you again bring up an "approved porsche list" into the discussion. have you ever worked or partnered with a german company before? believe me those lists are strictly business agreements, and have nothing do do with performance. the fact that the manual suggests that the oil pressure light coming on is ok, is more the reason to beware. in most cases, im sure this is not an issue, especially at idle. however, it could be a cover-up for a known issue with the choice of the "partnered preferred" oil, so their shops dont get buried with concerned customers in texas in the summer time.
You and i both know, most oil is find for general purpose, but the fact that i have been racing for so long with none of the issues of the 10 or so blown engines using mobil 1 at the track, should not be totally discounted or ignored. sure, ill admit, there is a little bit of brand loyalty on my part due to what i have read and seen, as well as experienced. Not too many 928 racers have as much time on an original engine as i do. the fact that it has lasted so long, against all odds, is something to take note of. (ie no oil cooler, no accusump, and running times that rival any of the top Grand Am Cup GS racers in the world)Its not so much the fact that the oil pressure isnt sufficient at 4 bar, but the indication that some thermal breakdown is occuring and that that maybe an indication that the oils protective qualities are going down at the higher temps.
at the bearing, if the oil is marginally protectiing due to high temp, that could be an issue. It is "generally " accepted that oil starvation is the cause, but that is also a theory. It is just as likely that it could be caused by themal breakdown of the oil or som eother related cause. folks have lost motors that have accusumps, drilled cranks, but the most common denominator has been Mobil 1. Since none of us work for the oil companies, and that includes me, i pick the things others have used to be successful with. at least, its cheap insurance.
mk
Originally Posted by Doug Hillary
Hi,
Mark - Back to rubbishing Mobil again? Its sure been your pattern for some years now!
Isn't it generally accepted that OIL STARVATION is the MOST LIKELY cause of the failures in the 2/6 bearing area??
Gauge INDICATED oil pressure has VERY LITTLE to do with the OPERATING OIL PRESSURE within a Journal bearing as they typically run at many hundreds of PSI and way beyond what you see on your gauge!! What is extremely important is FLOW!! Both for supply and cooling purposes - oil pressure just indicates the restriction to flow
The three oils you mention all have differing HTHS viscosities (@ 150C) so a variance will be evident -and as much as 10%. They are all way above Porsche's prescribed minimum of 3.5cSt and this is the "film strength" you perhaps allude to
As both the "other" oils have not submitted their products for ACEA testing we know very little about their oxidation and extended viscosity/shear relationships. We also do not know the levels of the silaxanes and silicone, organic copolymers that control foaming and how durable they really are
And Mark the "shearing" performance is very important indeed
But then we have covered all this before on here haven't we!
Porsche never saw it necessary to issue a TSB saying that 4bar at 2000rpm was not enough OP - even the Driver's Handbook says to expect the oil light to flicker or come on at a very hot idle!!!!
You said: "the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!"
Mark, the Used Oil Analysis (UOA) of your own oil was only an "average" result - no better and in some cases worse than the many others I now store on 928s that use a variety of oils!
A number probably would have done the same or even a better job!
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
Mark, one tends to suspect you "sell" Amsoil!!! I DON'T sell Mobil or any other product!!!
Keep using Amsoil Mark it suits your purpose well and they are good products too but it would seem much more professional not to constantly "knock" what others use with great success throughout the World.
And I DON'T use Mobil 1 in my 928!!!!
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
Mark - Back to rubbishing Mobil again? Its sure been your pattern for some years now!
Isn't it generally accepted that OIL STARVATION is the MOST LIKELY cause of the failures in the 2/6 bearing area??
Gauge INDICATED oil pressure has VERY LITTLE to do with the OPERATING OIL PRESSURE within a Journal bearing as they typically run at many hundreds of PSI and way beyond what you see on your gauge!! What is extremely important is FLOW!! Both for supply and cooling purposes - oil pressure just indicates the restriction to flow
The three oils you mention all have differing HTHS viscosities (@ 150C) so a variance will be evident -and as much as 10%. They are all way above Porsche's prescribed minimum of 3.5cSt and this is the "film strength" you perhaps allude to
As both the "other" oils have not submitted their products for ACEA testing we know very little about their oxidation and extended viscosity/shear relationships. We also do not know the levels of the silaxanes and silicone, organic copolymers that control foaming and how durable they really are
And Mark the "shearing" performance is very important indeed
But then we have covered all this before on here haven't we!
Porsche never saw it necessary to issue a TSB saying that 4bar at 2000rpm was not enough OP - even the Driver's Handbook says to expect the oil light to flicker or come on at a very hot idle!!!!
You said: "the fact now that i see such a dramatic difference in oil pressure when HOT, is warning enough for me that an oil that exhibits better thermal changes is the one i will use in my race. after all, its hard to argue with 77 race days and going on its 6 season of racing all on Amzoil!"
Mark, the Used Oil Analysis (UOA) of your own oil was only an "average" result - no better and in some cases worse than the many others I now store on 928s that use a variety of oils!
A number probably would have done the same or even a better job!
If it was oil pressure that really concerns you I thought you may have tried the "racing" oil I mentioned to you previously on here - Castrol's "R" or "Edge" 10w-60.
I assisted in developing this wonderful fully synthetic oil during the late 1970s and early 1980s, but its not for every day use in a 928 even if it was once on their Approved oils List
Mark, one tends to suspect you "sell" Amsoil!!! I DON'T sell Mobil or any other product!!!
Keep using Amsoil Mark it suits your purpose well and they are good products too but it would seem much more professional not to constantly "knock" what others use with great success throughout the World.
And I DON'T use Mobil 1 in my 928!!!!
The oil's Brand doesn't matter a Rat's tail if the specification is correct - that's why Porsche has about 100 lubricants on their TSB - but none from Amsoil?
Regards
05-08-2007, 01:40 PM
#22
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Lifted from another discussion...."Posted: Fri Apr 27, 2007 6:00 pm Post subject:
--------------------------------------------------------------------------------
This is not a true statement. Mobil 1 is not made the same as Castrol, hence the court case between the two. This is why there is now a group 1-4 category to add to the confusion of what oil to choose.
Let me explain as you did not include the differences between the four groups.
There Are Four Different Types of Motor Oil Base Stocks, We all know that basestock composition has a significant effect on the overall performance of motor oil. There are four different types of base stock used in the motor oil market today:
Group 1 - Conventional - Mineral oil derived from crude oil
Group 2 - Hydroprocessed - Highly refined mineral oil
Group 3 – Severe hydroprocessed - Ultra refined mineral oil
Group 4 – Full synthetics (chemically derived) - Chemically built Polyalphaolefins (PAO).
As it infers Groups 1 – 3 basestocks are derived from crude oil pumped from the ground whereas Group 4 basestocks are chemically derived, most often from ethylene gas, and contain none of the contaminants present in mineral oils. Just as distilled water is pure water derived from gas so is Group 4 basestocks which are pure oils derived from gas.
Is Mobil 1 a fully synthetic oil? Yes, it is. Mobil 1 uses high performance synthetic fluids, including polyalphaolefins (PAO), along with a proprietary system of additives. So it is classed as a group 4 oil.
Castrol is Severe hydroprocessed mineral oil so it is a not a fully synthetic oil, thus it is a group 3 oil.
Why do I want API rated oil Well my engineering company manufactures products for the aviation industry. We work to extremely high standards, higher than that of the automotive industry and even though we use the highest grade materials and we adhere to strict design parameters. Once we send our products to two independent certification laboratories that test our product to a specific standard, they manage to find the weaknesses in our products. We have spent as much as 6 months fixing these weaknesses in order to meet the requirements. The same goes for oil, if your want to compare apples with apples then you need to compare identical tests and test methods. Otherwise any manufacturer will only display there best characteristics and omit there worst for marketing purposes. Any product will have strengths and weaknesses but the only true why compare products it to expose them to the same tests and requirements and then compare the overall result. " .....
This points out that the definition of "synthetic oil" was changed by the court case and what Castrol was selling as synthetic is the Ultra refined mineral oil ......somehow that just does not seem right
--------------------------------------------------------------------------------
This is not a true statement. Mobil 1 is not made the same as Castrol, hence the court case between the two. This is why there is now a group 1-4 category to add to the confusion of what oil to choose.
Let me explain as you did not include the differences between the four groups.
There Are Four Different Types of Motor Oil Base Stocks, We all know that basestock composition has a significant effect on the overall performance of motor oil. There are four different types of base stock used in the motor oil market today:
Group 1 - Conventional - Mineral oil derived from crude oil
Group 2 - Hydroprocessed - Highly refined mineral oil
Group 3 – Severe hydroprocessed - Ultra refined mineral oil
Group 4 – Full synthetics (chemically derived) - Chemically built Polyalphaolefins (PAO).
As it infers Groups 1 – 3 basestocks are derived from crude oil pumped from the ground whereas Group 4 basestocks are chemically derived, most often from ethylene gas, and contain none of the contaminants present in mineral oils. Just as distilled water is pure water derived from gas so is Group 4 basestocks which are pure oils derived from gas.
Is Mobil 1 a fully synthetic oil? Yes, it is. Mobil 1 uses high performance synthetic fluids, including polyalphaolefins (PAO), along with a proprietary system of additives. So it is classed as a group 4 oil.
Castrol is Severe hydroprocessed mineral oil so it is a not a fully synthetic oil, thus it is a group 3 oil.
Why do I want API rated oil Well my engineering company manufactures products for the aviation industry. We work to extremely high standards, higher than that of the automotive industry and even though we use the highest grade materials and we adhere to strict design parameters. Once we send our products to two independent certification laboratories that test our product to a specific standard, they manage to find the weaknesses in our products. We have spent as much as 6 months fixing these weaknesses in order to meet the requirements. The same goes for oil, if your want to compare apples with apples then you need to compare identical tests and test methods. Otherwise any manufacturer will only display there best characteristics and omit there worst for marketing purposes. Any product will have strengths and weaknesses but the only true why compare products it to expose them to the same tests and requirements and then compare the overall result. " .....
This points out that the definition of "synthetic oil" was changed by the court case and what Castrol was selling as synthetic is the Ultra refined mineral oil ......somehow that just does not seem right
05-08-2007, 01:46 PM
#23
Man of many SIGs
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Mark,
if you feel that the 928 has higher than average oil temps ( above 280 degrees) why aren't you using an oil cooler? It seems like it would be prudent to do so.
if you feel that the 928 has higher than average oil temps ( above 280 degrees) why aren't you using an oil cooler? It seems like it would be prudent to do so.
05-08-2007, 02:02 PM
#24
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Thread Starter
Scot and i only see 260F oil temps and that is not far out of the normal racing heat ranges. scot is too cheap to get one, but he should and my temps with the oil cooler in the radiator brings my temps down by about 10F from his.
the 280F temps are only seen on 100F ambient race days.
mk
the 280F temps are only seen on 100F ambient race days.
mk
Originally Posted by Fabio421
Mark,
if you feel that the 928 has higher than average oil temps ( above 280 degrees) why aren't you using an oil cooler? It seems like it would be prudent to do so.
if you feel that the 928 has higher than average oil temps ( above 280 degrees) why aren't you using an oil cooler? It seems like it would be prudent to do so.
05-08-2007, 02:52 PM
#25
Under the Lift
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Originally Posted by mark kibort
thermal breakdown is quite a bit worse with mobil 1.
MK
MK
05-08-2007, 06:31 PM
#28
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Thread Starter
what i mean is that I'm talking about what the oil goes through at 280F. if all things are equal at start up and at moderate temps, then what do you call the fact that the mobil 1 looses so much oil pressure at race temps? im sure it is not a factor for what you are doing at such high speeds. you dont have to pull the gs and you are looking at water temp, which really doesnt directly correlate with oil temps. But, lets say that you are at 260ish F temps, and the oil pressure is at 5 bar, then the only difference could be in the viscosity of the oil at that temp or its protective qualities. All i can say, is that when i saw the noticble pressure changes when HOT, i started to question the use of that oil.
maybe ive just had good luck, but thats a lot of good luck!
MK
maybe ive just had good luck, but thats a lot of good luck!
MK
Originally Posted by Bill Ball
"Thermal breakdown"? What do you mean by that? I think "thermal breakdown" is a term used to describe decomposition of the oil formulation. M1 is very stable at high temperatures. I think running in the desert at 100F with my cooloant temp gauge just below the redzone for 50-80 miles at a time averaging 145MPH is a whole lot of heat stress. And in a car with 180K miles on the motor, oil pressure has never been an issue with M1 15W 50.
05-08-2007, 06:38 PM
#29
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Given that the refining process occurs at temps of ....." The steps of fractional distillation are as follows:
You heat the mixture of two or more substances (liquids) with different boiling points to a high temperature. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius. ........ " It would seem that what ever happens in an engine is mild by comparison.
You heat the mixture of two or more substances (liquids) with different boiling points to a high temperature. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius. ........ " It would seem that what ever happens in an engine is mild by comparison.
05-08-2007, 08:59 PM
#30
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Thread Starter
so i wonder why the oil pressure changes so much at the "mild " temperatures between the two oils, and if one thins more than another, could it be a factor in a bearing failure in our cars?
mk
mk
Originally Posted by Jim bailey - 928 International
Given that the refining process occurs at temps of ....." The steps of fractional distillation are as follows:
You heat the mixture of two or more substances (liquids) with different boiling points to a high temperature. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius. ........ " It would seem that what ever happens in an engine is mild by comparison.
You heat the mixture of two or more substances (liquids) with different boiling points to a high temperature. Heating is usually done with high pressure steam to temperatures of about 1112 degrees Fahrenheit / 600 degrees Celsius. ........ " It would seem that what ever happens in an engine is mild by comparison.