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I've just had 6L of EE Performance 0w20 arrive today. The filter and oil analysis kit are due before the weekend, so with any luck I'll be able to send the oil sample off Monday and report back shortly after 👍
I might put an extra note in with the sample, with some context to this thread?

Thinking about it... it might be good if long term, Millers give not just a general reading with regards to wear metals but if they were more common in different engines/platforms?
 

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Discussion Starter · #22 ·
Sounds good Kaviar, I also gave them a brief outline of why I was doing this and my 0w20 oils/trackdays use.

I thought I would email Millers regarding my last analysis and ask about the fuel content on the basis of my concern and what BRZ was saying. I didn't want to bother them but the contact said I could ask questions and they have been very helpful. I assume they won't mind me putting the reply here, and while some of it may be familiar its better that it comes from a laboratory manager instead of internet speculation. Its not GT86 specific but probably the most accurate oil specific info I have.

Hi

The fuel content is at a ‘caution’ level hence the big amber ?; the reason fuel dilution is important is that excessive fuel drops the viscosity and hence the protection to the engine. Your viscosity is in grade for an SAE 20 and so protection is not compromised.(one benefit of using low viscosity oils is the thinning effect of petrol is very much reduced as the oil viscosity is closer to that of petrol than would be the case with a high viscosity oil) Also, the fuel measured is a transitory value, it will boil off as the engine gets to temperature in contrast with diesel, which, being less volatile, accumulates until the oil must be changed.

Fuel in oil is caused by incomplete combustion and occurs during start up, when the engine is cold and during acceleration. Track days are notorious for causing fuel dilution as the engine is subject to full power condition for a large proportion of the time vs regular use, where the vehicle is at a cruise for the majority of the time. This is why, in motorsport, the oil is changed very regularly.

Another cause of fuel in oil is poor atomisation due to faulty or dirty injectors so you may wish to consider using an injector cleaner in a tank of fuel.

You haven’t had the engine remapped have you? (No) Some mappers like to use a rich mixture to keep combustion temperatures down and this can give issues with fuel in oil.

When driven at a cruise and the engine up to temperature, the oil is sufficiently hot to volatilise the fuel and it is vented through the PCV (positive crankcase ventilation) system. I would have expected that 300 miles of driving home would be sufficient to clear the oil of fuel. (assuming that your oil is not over cooled and runs at a normal, 105 oC ish temperature) (No oil cooler) The main suspect for the fuel found, therefore, is the 20 min warm up drive. (20min drive prior to drain and sample collection)

We call ‘caution’ at 2% and ‘critical’ at 4% for fuel but the main thing is that viscosity remains in grade, which yours does so don’t worry about it too much.



Regards
 

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Quick note before I reply in full...

Opie Oils have 15% off their site at the moment. Including the oil analysis kits!
Just used "Black" as the discount code at checkout 👍

I've not seen the kits any lower then the RRP or on offer anywhere else before. Might be worth stocking up on a few kits at a decent price?
 

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level hence the big amber ?; the reason fuel dilution is important is that excessive fuel drops the viscosity and hence the protection to the engine. Your vis
Quick note before I reply in full...

Opie Oils have 15% off their site at the moment. Including the oil analysis kits!
Just used "Black" as the discount code at checkout 👍

I've not seen the kits any lower then the RRP or on offer anywhere else before. Might be worth stocking up on a few kits at a decent price?
If you have not ordered it yet, Millers website have a pair to purchase at a lower price £54 ( without discount). Thats what i do generally
 

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Sounds good Kaviar, I also gave them a brief outline of why I was doing this and my 0w20 oils/trackdays use.

I thought I would email Millers regarding my last analysis and ask about the fuel content on the basis of my concern and what BRZ was saying. I didn't want to bother them but the contact said I could ask questions and they have been very helpful. I assume they won't mind me putting the reply here, and while some of it may be familiar its better that it comes from a laboratory manager instead of internet speculation. Its not GT86 specific but probably the most accurate oil specific info I have.

Hi

The fuel content is at a ‘caution’ level hence the big amber ?; the reason fuel dilution is important is that excessive fuel drops the viscosity and hence the protection to the engine. Your viscosity is in grade for an SAE 20 and so protection is not compromised.(one benefit of using low viscosity oils is the thinning effect of petrol is very much reduced as the oil viscosity is closer to that of petrol than would be the case with a high viscosity oil) Also, the fuel measured is a transitory value, it will boil off as the engine gets to temperature in contrast with diesel, which, being less volatile, accumulates until the oil must be changed.

Fuel in oil is caused by incomplete combustion and occurs during start up, when the engine is cold and during acceleration. Track days are notorious for causing fuel dilution as the engine is subject to full power condition for a large proportion of the time vs regular use, where the vehicle is at a cruise for the majority of the time. This is why, in motorsport, the oil is changed very regularly.

Another cause of fuel in oil is poor atomisation due to faulty or dirty injectors so you may wish to consider using an injector cleaner in a tank of fuel.

You haven’t had the engine remapped have you? (No) Some mappers like to use a rich mixture to keep combustion temperatures down and this can give issues with fuel in oil.

When driven at a cruise and the engine up to temperature, the oil is sufficiently hot to volatilise the fuel and it is vented through the PCV (positive crankcase ventilation) system. I would have expected that 300 miles of driving home would be sufficient to clear the oil of fuel. (assuming that your oil is not over cooled and runs at a normal, 105 oC ish temperature) (No oil cooler) The main suspect for the fuel found, therefore, is the 20 min warm up drive. (20min drive prior to drain and sample collection)

We call ‘caution’ at 2% and ‘critical’ at 4% for fuel but the main thing is that viscosity remains in grade, which yours does so don’t worry about it too much.

Regards
It was handy I waited to reply as I ended up calling Millers Oils today, to go though the difference between the classic and passenger car kits.

The chap I spoke too (sadly I've forgotten his name) was extremely helpful and insightful. He was one of, in not 'the' person who runs the analysis and having mentioned this thread, he gave be the same advice as above. So I believe he was the same guy who you've been speaking with EB?

Fuel Dilution
It's good to know that "a quick warm up" was the most likely the case of your high fuel dilution 👍
Based on the other info, I suspect that with with my oil cooler working "too well" on the road, this value will be quite poor on my results?
Also interesting they mention ~105c as being the normal temp. I'd always believed it to be a number in the mid/high 90s?

Valve Spring Recall Side Note
We had a good chat about the 86 and how analysis had become very popular, following valve spring recalls. All in an effort to keep track of any over zealous applications of silicone!
As a disclaimer, the chap I spoke too didn't suggest this in anyway... but I wonder if Toyota dealers themselves are sending in samples should a car come back with a failure post recall?
In an ideal world... I guess having an analysis done before and after the recall, would put people in a stronger position, should there ever be a failure?

If you have not ordered it yet, Millers website have a pair to purchase at a lower price £54 ( without discount). Thats what i do generally
I've done that before as well. Sadly, it looks like since the rebrand the twin pack has disappeared :(
 

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It was handy I waited to reply as I ended up calling Millers Oils today, to go though the difference between the classic and passenger car kits.

The chap I spoke too (sadly I've forgotten his name) was extremely helpful and insightful. He was one of, in not 'the' person who runs the analysis and having mentioned this thread, he gave be the same advice as above. So I believe he was the same guy who you've been speaking with EB?
Mike W is the main man. I have even sent his report feedback to Matt , Cosworth. Even he appreciated his comments on the oil analysis.
 
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