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Hi Luke,

Thanx for chiming in. I think that is a great report for 6000 km. I think the Aluminum is lab error. The worry would be that the cylinder liners are Lokasil which is aluminum with a silicon fiber matrix but your silicon levels are normal. I do not know of any bearings that contain aluminum in significant quantities. Pistons are aluminum but only the rings contact the cylinder walls under normal circumstances. If the cylinders were scored you would get both silicon, aluminum and metals from the rings like iron, moly and chrome, and at very high levels. Your aluminum is just barely elevated and everything else is fine.

If you drive your car in the winter you are not going to like that tranny oil. Millers EE 75 W90 Nanodrive is better. It has a higher viscosity index and is substantially thinner when cold. Still, below 32 F you are better off with Shell Spirax or Mobilube PTX. I use Shell in the winter and Millers in the Summer. These Aisen transmissions have an annoying amount of lash. The thicker Millers dampens it nicely during the warm months giving you nice smooth shifting but below freezing you need a crow bar to get into 1st and 2nd. So, it is back to Shell or Mobilube.

Edited by Mijostyn
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OK, here is where I'm at as of this juncture:   Everyone I have spoken to (oil company technical personnel, used oil analytical labs) has basically said the same thing:  When fuel dilutes the oil, a

Posted Images

Quite welcome Mijostyn,

As I mentioned, the CI-4+ M1 TDT is no longer available, but to be fair, the X-Cess 5W-40 produced even better UOA with ALL metals below or at averages. Great stuff for sure. I will post my CFS UOA later this year for sure. Give me a month or two.

I would not hesitate one moment to recommend X-Cess for a daily driven Carrera. Great fluid at a great price.

Regarding transmission fluid. I've been running the CRX 75W-90 NT for abour 300-400 km now. It has bedded in quite nicely and improved in cold shifting department as well. Last night my wife took my C2S for a drive. When she came back, her first words were: "the tranny shifts really nice!". I kid you not. And trust me, she does not give a flying fig about lubricants, like I do.

I've seen already about freezing point in the morning and shifting is quite comparable to P-approved fluid at the same temperatures. Perhaps a tad notchier, but not much.

Keep in mind that shifing may be a function of many other parts including clutch assembly, linkage, etc. as well.

Yes, I was quite intrigued by that EE 75W-90 NT. I will give it a shot next spring after we wake up from winter hibernation.

Its KV should be around 830 cSt at freezing point IIRC, much lower than CRX NT and a lot closer to P-required 600 cSt at 0*C.

I have good access to Sheel S5 ATE 75W-90 (P-approved) and Millers (I also sell Millers products where I live). So much for lifetime fill in the tranny, right? Ha, ha, ha....

Yes, Millers dampens really well all gears inside those G-boxes. And engines too. Much quiter engine compared to M1 0W-40 as an example. But I am biased, so don't listen to me.

Happy motoring!

Luke

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Keep that Shell handy Luke. Up there in Calgary you are going to need it!! It is the baulk rings. Once the oil gets too thick they won't clutch correctly. Everything just keeps spinning at different speeds. Nothing else much matters. Cool you know about Porsche's spec. The oil has to be thinner than 600 cSt at 0 C. The only two that meet that spec are the Shell S5 ATE and the Mobilulbe PTX. Anybody know what a centi Stoke is??

Anyway, it sounds like you put the car up for the winter. I still think you will like the EE better. Its kinematic viscosity is around 17 cSt at 100C which is thick for a 75W 90. Dampens that hypoid final drive nicely.

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Jl-c, water condensation may boil off because water molecules are polar. Fuel and oil are both non polar hydrocarbons. Once fuel is dissolved in the oil it will not boil off and the drop in viscosity is permanent.

I don't agree with this statement. Gasoline boiling point is 25 - 75*C. It will boil out of oil which is much heavier at about 300-400*C boiling point. It's called fractionation and has nothing to do with polar nature of gases or fluids. That is how gases, gasolines, naphtha, kerosene, oils, etc. are extracted from crude oil. Edited by luxter
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Hold on Luke,

You are talking about fractional distillation. Crude oil is vaporized at a temperature of about 1000 F. The vapor then rises in a cooling tower. As the oil vapor cools on the way up the various fractions condense at their boiling points on plates which are piped to various holding tanks. Key point, you have added enough energy, in the form of heat to separate ALL of the crude oil molecules from each other. The separation process occurs as the vapor condenses.

Oil temp in Cars is held at just above water's boiling point of 212 F.... To make sure the oil stays dry. Remember, when you burn any hydrocarbon you get mostly carbon dioxide and ...water. The stuff dripping out of your tail pipe. Although gasoline has a substantially lower boiling point than oil in order to separate the two you have to vaporize the lot and catch the fractions as they condense. This does not happen in a car engine. However, water molecules being polar will boil off as they are repulsed by the non polar oil molecules. Try mixing olive oil in water. You can do it actually if you apply enough agitation to emulsify the mixture. This is what happens when coolant leaks into the oil usually via a blown head gasket. Looks sort of like a chocolate frap. You can still separate the two by just heating up the mixture. The oil will rise to the top. Not an experiment I would care to try. Mix gasoline in oil. The gasoline dissolves instantly. Now heat up the mixture. Does the gasoline float to the top?? This reminds me of those folks burning their house to the ground with a turkey fryer.

Edited by Mijostyn
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  • 5 months later...

Hey guys,

PORSCHE-M97-E-I-952178-Sev3.pdf

This is my most recent oil report. Notice the report also compares the most current data with the preceding test. The nickle and oxidation are not real. They are errors and by products of the test Polaris uses in combination with Millers oil. The dilution and viscosity numbers are real. Notice the dilution increasing. It is just at the point the oil needs to be replaced at 6,000 miles! No oil will make it gracefully to 10,000 mile in my car, the way I drive. Also you see the TBN ( base number) dropping. It is also now at the point the oil needs replacement! I alway replace my oil if the TBN drops below 3.

Edited by Mijostyn
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  • 3 weeks later...

What does Polaris charge for the oil analysis including TBN Mijostyn? I've used Blackstone.

Hey Kid. I buy several collection sets at a time. $25.00 per collection set. That covers everything. The set is a sample bottle and mailer, labels etc.

I just drop the oil filter canister and the oil that is left in it is more than enough to fill the sample bottle. I always replace the filter. You lose about 1/2 liter in the process. Don't forget to clean of the canister well before you drop it. Any contamination screws up the test. I use brake cleaner spray followed by a compressed air blast.

The TBN is part of the normal profile. It is a package deal. They then give you the report online. Usually takes them about 10 days.

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  • 2 weeks later...

......

No oil will make it gracefully to 10,000 mile in my car, the way I drive. Also you see the TBN ( base number) dropping. It is also now at the point the oil needs replacement! I alway replace my oil if the TBN drops below 3.

Interesting, my TBN dropped to 8.4 after about 7,400 kms last year. Need to find my UOA and post it. Too busy with daily stuff.

The oxidation was above 50 but Millers say it starts at about 45 or so. The KV was at low 12 IIRC.

I think we were talking with Harry about your high nickel in UK last fall trying to understand where it came from.

Otherwise wear metals look good. Great oil without a doubt.

In fact Hartech UK recommend CFS 10W-50 in all water cooled 996 and 997's.

Cheers,

Luke

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Nice picture Luxter, it pretty much explains things but does not give you an idea of the scale. These towers are HUGE. Not exact sure but they are at least 4 stories tall.

The nickel levels are false. Something about the nano particles screws up the test that Polaris uses. Harry and I both talked to Millers and it is absolutely nothing to worry about. All our other wear metals are excellent. I change the oil 6000 miles because of the falling TBN and fuel dilution. The CSF 5W40 starts out a bit thicker than Mobil 0W40 to start. By the time my oil is diluted 3% it has probably dropped to the viscosity of the Mobil. Some how I get the feeling that some of the problems with cylinders scoring and bearings failing may be due to this. People running their oil out to 10,000 miles may reach up to 5% dilution if their engine is like mine and there must be quite a few. That is more than enough to drop the oils viscosity one whole grade. But also the oil's lubricity drops. It does not reduce friction as well. The CSF nano oils also have a lot more ZDDP in them which helps cut friction quite a bit. I have to say my engine runs like a top and is smooth as silk. The only issue with the Millers is the price.

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Hey,

I've been in oil and gas for last 20 years, so happen to see, climb, inspect, etc. these towers. Stinky business.

Yes, don't worry about nickel.

There is direct correlation between KV 100C, HTHS and film strength. I don't have this doc handy but all three trend he same way. The easiest way is to monitor your oil pressure at idle in the same temperature. You will eventually see a slight drop in pressure. A good indication of oil dropping its KV. The CFS indeed is a bit thicker than M1 but not much. Both are on thin side of 40 grade. My suggestion blend some 10W-50 (say 10%) with 5W-40 to help your fuel dilution.

The other issue never mentioned previously is that 996/997 don't drain oil completely. There will be always about 1L of old oil left inside the engine. That old oil very quickly contaminates your fresh fill. Yet another reason to change oil frequently.

I'm also hoping that the nano onions help with IMSB and bore scoring.

My experience with Millers oils matches yours. To me price is not an issue. These engines are +$35K.

Good to hear from you, all the best, keep posting.

I'll try to visit more often, as soon as get through my divorce.

Cheers,

Luke

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  • 2 months later...

Here's the latest oil sample... This time after running Miller's Nano. This is daily driven, 20+ miles a day which is barely enough time to heat up engine fully. Things improved. Also cut open filter and not a spec of metal anywhere and nothing on magnetic drain plug. I haven't seen another 997 Carrera S with as many miles as mine has and these numbers look pretty good. Test recomends running Miller's to 7,000 miles, which is a pretty high end oil...so how do the OEM's have 12,000 to 15,000 mile recomended oil changes on normal oil? Something isnt right...

post-25218-0-86938800-1406253936_thumb.j

Edited by Dus10R
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Here's the latest oil sample... This time after running Miller's Nano. This is daily driven, 20+ miles a day which is barely enough time to heat up engine fully. Things improved. Also cut open filter and not a spec of metal anywhere and nothing on magnetic drain plug. I haven't seen another 997 Carrera S with as many miles as mine has and these numbers look pretty good. Test recomends running Miller's to 7,000 miles, which is a pretty high end oil...so how do the OEM's have 12,000 to 15,000 mile recomended oil changes on normal oil? Something isnt right...

Nice improvement. With your elevated metals, I'd keep changing at the 5,000 mile interval. You only have 2 data points (2 tests)......but at least the numbers appear to be dropping. Once the numbers level out, then maybe push the interval by a 1,000 miles or 2,000.

 

Got to love the zinc and phosphate levels. Nice!!

 

Maybe the viscosity is on the low end for a 5W40 because the Miller's is fighting with the prior oil that was in the system. This is common. Additive packages fight each other from brand to brand. Look for that to improve at your next test since the concentration (you never get all the old oil out with an oil change) of the Miller's will now be much closer to 100%. Maybe you can find data for a VOA (virgin oil analysis) on the Miller's and see where the viscosity starts. Ask Miller if they have this, or search the Bob The Oil Guy web site.

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Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them.

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Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them

 

 

 

Hey jl-c, I just put Edge 5W 40 in the Turbo S. This is what Audi uses so I have a common oil with My wife's SQ5 for the time being. I plan to switch both cars to Millers after they hit 10,000 miles (broken in). That Porsche recommendation is only 1/2 right. Moisture (H2O) does indeed boil off as you heat up the oil but fuel does not. Once the oil is diluted with fuel it is permanent. If you look at the UOAs of my C4S as you get more miles the fuel dilution only increases in a linear fashion. By 6,000 miles the oil is diluted enough to lose a viscocity grade. So, I do not go longer than 6000 mile between oil changes in that car. Each car is different so, the only way to know what is going on with your car is to run serial UOAs until you have it figured out. Porsche's recommended oil change interval is more political than anything. You can go 10,000 miles but I wouldn't, at least not in my C4S.

 

Millers is the absolute best as Luke's, mine and now Dus10R's experience shows. I am absolutely sure that wear rates fall off with this oil formulation.

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Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them

 

 

 

Hey jl-c, I just put Edge 5W 40 in the Turbo S. This is what Audi uses so I have a common oil with My wife's SQ5 for the time being. I plan to switch both cars to Millers after they hit 10,000 miles (broken in). That Porsche recommendation is only 1/2 right. Moisture (H2O) does indeed boil off as you heat up the oil but fuel does not. Once the oil is diluted with fuel it is permanent. If you look at the UOAs of my C4S as you get more miles the fuel dilution only increases in a linear fashion. By 6,000 miles the oil is diluted enough to lose a viscocity grade. So, I do not go longer than 6000 mile between oil changes in that car. Each car is different so, the only way to know what is going on with your car is to run serial UOAs until you have it figured out. Porsche's recommended oil change interval is more political than anything. You can go 10,000 miles but I wouldn't, at least not in my C4S.

 

Millers is the absolute best as Luke's, mine and now Dus10R's experience shows. I am absolutely sure that wear rates fall off with this oil formulation.

 

 

I'm not sure I can agree with your comments on fuel dilution.  Nearly all the components in gas have considerably higher vapor pressures than water, so if the water is boiling off, the fuel should have preceded it.  I think the issue may be how (the analytical technique) your UOA lab is measuring fuel dilution, they may be seeing accumulating fuel additive's that remain after the fuel actually flashed off, which would give the impression of increasing fuel dilution with time.

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Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them

 

 

 

Hey jl-c, I just put Edge 5W 40 in the Turbo S. This is what Audi uses so I have a common oil with My wife's SQ5 for the time being. I plan to switch both cars to Millers after they hit 10,000 miles (broken in). That Porsche recommendation is only 1/2 right. Moisture (H2O) does indeed boil off as you heat up the oil but fuel does not. Once the oil is diluted with fuel it is permanent. If you look at the UOAs of my C4S as you get more miles the fuel dilution only increases in a linear fashion. By 6,000 miles the oil is diluted enough to lose a viscocity grade. So, I do not go longer than 6000 mile between oil changes in that car. Each car is different so, the only way to know what is going on with your car is to run serial UOAs until you have it figured out. Porsche's recommended oil change interval is more political than anything. You can go 10,000 miles but I wouldn't, at least not in my C4S.

 

Millers is the absolute best as Luke's, mine and now Dus10R's experience shows. I am absolutely sure that wear rates fall off with this oil formulation.

 

 

I'm not sure I can agree with your comments on fuel dilution.  Nearly all the components in gas have considerably higher vapor pressures than water, so if the water is boiling off, the fuel should have preceded it.  I think the issue may be how (the analytical technique) your UOA lab is measuring fuel dilution, they may be seeing accumulating fuel additive's that remain after the fuel actually flashed off, which would give the impression of increasing fuel dilution with time.

 

 

It has nothing to do with vapor pressure JFP. It has to do with solubility and the polarity of the various molecules. I discussed this before when I explained fractional distillation. This is a mistake many people make. The UOAs are quite predictible in this reguard and reasonably accurate. Fuel does not boil off once it is desolved in oil. In order to separate it you have to heat it all up to 1000 degrees and catch the molecules as they condense. This is how oil refineries work. Non polar molecules attract each other in solution but repell polar molecules such as water. This is why the water boils off.

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Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them

 

 

 

Hey jl-c, I just put Edge 5W 40 in the Turbo S. This is what Audi uses so I have a common oil with My wife's SQ5 for the time being. I plan to switch both cars to Millers after they hit 10,000 miles (broken in). That Porsche recommendation is only 1/2 right. Moisture (H2O) does indeed boil off as you heat up the oil but fuel does not. Once the oil is diluted with fuel it is permanent. If you look at the UOAs of my C4S as you get more miles the fuel dilution only increases in a linear fashion. By 6,000 miles the oil is diluted enough to lose a viscocity grade. So, I do not go longer than 6000 mile between oil changes in that car. Each car is different so, the only way to know what is going on with your car is to run serial UOAs until you have it figured out. Porsche's recommended oil change interval is more political than anything. You can go 10,000 miles but I wouldn't, at least not in my C4S.

 

Millers is the absolute best as Luke's, mine and now Dus10R's experience shows. I am absolutely sure that wear rates fall off with this oil formulation.

 

 

I'm not sure I can agree with your comments on fuel dilution.  Nearly all the components in gas have considerably higher vapor pressures than water, so if the water is boiling off, the fuel should have preceded it.  I think the issue may be how (the analytical technique) your UOA lab is measuring fuel dilution, they may be seeing accumulating fuel additive's that remain after the fuel actually flashed off, which would give the impression of increasing fuel dilution with time.

 

 

It has nothing to do with vapor pressure JFP. It has to do with solubility and the polarity of the various molecules. I discussed this before when I explained fractional distillation. This is a mistake many people make. The UOAs are quite predictible in this reguard and reasonably accurate. Fuel does not boil off once it is desolved in oil. In order to separate it you have to heat it all up to 1000 degrees and catch the molecules as they condense. This is how oil refineries work. Non polar molecules attract each other in solution but repell polar molecules such as water. This is why the water boils off.

 

 

I am going to have to look into this subject a bit deeper; I am find many references to the fuel dilution flashing off when an engine reaches both full operating temperatures, and some level of vacuum in the sump, and nothing (yet) to support your point.  We will come back to this topic.................

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It is funny how we develop these mythologies. Humans are funny creatures. When we do not know what is going on we make stuff up! Then the made up stuff gets a life and away we go. A good example is the gluten fad. I have to deal with this stuff every day. Most of the myths have some basis in reality. All substances have a vapor pressure which varies based on the nature of the substance and temperature. The molecules in gas as a conglomerate have a higher vapor pressure than the conglomerate molecules in motor oil. But, when you put them in solution together all bets are off. Think of it this way. Is the vapor in your crank case near as explosive as the vapor in a gas can. It does not take much gas vapor to cause quite the explosion!

 

 

 

 

 

Luxter, reading the manual. (we all do don't we?) it appears that Porsche agree with you and what I did to boil off excess fuel/condensation from my oil, I quote:-

Engine Oil

Engine oil consumption

It is normal for your engine to consume oil.

The rate of oil consumption depends on the quality

and viscosity of oil, the speed at which the engine

is operated, the climate, road conditions as well

as the amount of dilution and oxidation of the

lubricant.

If the vehicle is used for repeated short trips, and

consumes a normal amount of oil, the engine oil

measurement may not show any drop in the oil

level at all, even after 600 miles (1,000 km) or

more. This is because the oil is gradually becoming

diluted with fuel or moisture, making it appear

that the oil level has not changed.

The diluting ingredients evaporate out when the

vehicle is driven at high speeds, as on an expressway,

making it then appear that oil is excessively

consumed after driving at high speeds.

If the conditions you drive your vehicle in are

dusty, humid, or hot, the frequency of the oil

change intervals should be greater.

 

Seek and ye shall find  :D

Oil change this weekend (6,000 m), going away from Mobil 1 and using Castrol Edge 5W 40, but have just purchased oil for the next change and gone for the Millers Oils NANODRIVE CFS 5w-40 NT as recommended on here. Time will tell which suits the best. Intend to get analysis done every 3,000 m to keep an eye on things and get a comparison between them

 

 

 

Hey jl-c, I just put Edge 5W 40 in the Turbo S. This is what Audi uses so I have a common oil with My wife's SQ5 for the time being. I plan to switch both cars to Millers after they hit 10,000 miles (broken in). That Porsche recommendation is only 1/2 right. Moisture (H2O) does indeed boil off as you heat up the oil but fuel does not. Once the oil is diluted with fuel it is permanent. If you look at the UOAs of my C4S as you get more miles the fuel dilution only increases in a linear fashion. By 6,000 miles the oil is diluted enough to lose a viscocity grade. So, I do not go longer than 6000 mile between oil changes in that car. Each car is different so, the only way to know what is going on with your car is to run serial UOAs until you have it figured out. Porsche's recommended oil change interval is more political than anything. You can go 10,000 miles but I wouldn't, at least not in my C4S.

 

Millers is the absolute best as Luke's, mine and now Dus10R's experience shows. I am absolutely sure that wear rates fall off with this oil formulation.

 

 

I'm not sure I can agree with your comments on fuel dilution.  Nearly all the components in gas have considerably higher vapor pressures than water, so if the water is boiling off, the fuel should have preceded it.  I think the issue may be how (the analytical technique) your UOA lab is measuring fuel dilution, they may be seeing accumulating fuel additive's that remain after the fuel actually flashed off, which would give the impression of increasing fuel dilution with time.

 

 

It has nothing to do with vapor pressure JFP. It has to do with solubility and the polarity of the various molecules. I discussed this before when I explained fractional distillation. This is a mistake many people make. The UOAs are quite predictible in this reguard and reasonably accurate. Fuel does not boil off once it is desolved in oil. In order to separate it you have to heat it all up to 1000 degrees and catch the molecules as they condense. This is how oil refineries work. Non polar molecules attract each other in solution but repell polar molecules such as water. This is why the water boils off.

 

 

I am going to have to look into this subject a bit deeper; I am find many references to the fuel dilution flashing off when an engine reaches both full operating temperatures, and some level of vacuum in the sump, and nothing (yet) to support your point.  We will come back to this topic.................

 

 

Anyway, Just call Millers oil in England. I bring up Millers because you can actually get to someone who knows what they are talking about and they can be most helpful. I doubt you will get the same treatment from Mobil or Shell.

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More to the point, I've been talking to labs that do UOA work, and a couple have told me that if a lab is using flash point analysis (cheap, quick, but grossly inaccurate) to determine fuel dilution levels, that alone can generate results similar to what you saw.  From my discussion's with them, the recommended method to do fuel dilution in engine oils is by head space gas chromatography, or by flame ionization chromatography.   While they seem to feel that flame ionization is the more accurate of the two methods, both only heat the oil sample to 300F to get the fuel off for measurement in the dector.  That point alone seems to contradict your theory.

 

I'm going to keep digging on this subject.  I have inquiries into contacts I have inside the oil industry (started my career off working in the R&D group of one of the then big ones) to see if they can shed any light on the subject.

 

Stay tuned.................

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Excellent. I'll check with Polaris to see which method they are using, but no It does not contradict my theory which is really not my theory at all. I am just parroting what I learned. They are probably looking at the concentration of a specific molecule found in gas but not in oil. If you know the concentration of that molecule in both clean gas and clean oil then once you determine the concentration of that molecule in the "dirty" oil vapor you also now know what its concentration in the "dirty" oil is. They have to vaporize the mess for the test to work. I am not sure how inaccurate flash point analysis is but you are certainly not directly measuring fuel dilution. The other tests directly measure the concentration probably of specific molecules. I wonder how the various formulas the oil blenders use affect these tests as well as there may be some variation in gasoline composition. But, when I think about it all this is essentially null as I am sure Polaris used the exact same test on all my oil samples and there is an undeniable trend. The 1st sample at 1000 miles o.75 % diluted, the 2nd at 3000 miles 1.6 % diluted then at 6000 3.4% diluted. The fuel is certainly not vaporizing off faster than the oil is being diluted over a period of about 7 months!

 

More to the point, I've been talking to labs that do UOA work, and a couple have told me that if a lab is using flash point analysis (cheap, quick, but grossly inaccurate) to determine fuel dilution levels, that alone can generate results similar to what you saw.  From my discussion's with them, the recommended method to do fuel dilution in engine oils is by head space gas chromatography, or by flame ionization chromatography.   While they seem to feel that flame ionization is the more accurate of the two methods, both only heat the oil sample to 300F to get the fuel off for measurement in the dector.  That point alone seems to contradict your theory.

 

I'm going to keep digging on this subject.  I have inquiries into contacts I have inside the oil industry (started my career off working in the R&D group of one of the then big ones) to see if they can shed any light on the subject.

 

Stay tuned.................

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Thanks, but unfortunately, none of these address it issue of fuel dilution concentration accuracy between the two types of tests (flash point vs. GC or FI), which I have told is considerable; plus the fact that flash point analysis can be misinterpreted due to the impact of other factors on the oil which tend to give higher volatile's concentrations which are falsely attributed to increasing fuel dilution.

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