Indeed, though that would mean the oil dilution level could be even worse - as the soot will have countered some of the thinning. So sadly it still suggests that the RR was right in thinking it needs a oil change.

The UK company who brokered the oil analysis are going to re test my oil.

James

Given that we know my oil is at the edge of ruined by oil dilution it might be interesting to do a home, low tech, measure of its viscosity as a bench mark.

I could heat the oil to 100 degrees and pour it through a funnel with a known sized small aperture, or a length of tube (to increase the time deltas).

If the difference between new oil poured through it and my 'old' oil poured through it is significant enough then it might be a cheaper way for other people to check their oil than pay for a lab. The difference might not be significant enough of course!


James

From a scientific viewpoint.......;
There is no way to conclude there is any oil dilution and the only test shows no fuel in the oil
There is evidence of the oil being a lower viscosity than the label on the tin but that's not the same as saying it's diluted with fuel. Correlation is not the same as causation  2012 TDV8 Vogue (L322)

I’m a PhD level scientist and work in the oil industry around spill response and deal with viscosity changes etc all the time when oil and water interact. Take it from me, don’t waste your time and get it looked at as per previous posts is my advice
Air leaks are your enemy #1  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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JayGee wrote:

From a scientific viewpoint.......;
There is no way to conclude there is any oil dilution and the only test shows no fuel in the oil
There is evidence of the oil being a lower viscosity than the label on the tin but that's not the same as saying it's diluted with fuel. Correlation is not the same as causation

Very true, any home experiment that found the oil to have lowered in viscosity doesn't prove that lowering is because of fuel dilution. It would be like counting corpses in a mortuary to decide the number of covid deaths.

However.. the fact there is a lowering of viscosity means you need to change your oil regardless of the cause, so perhaps it doesn't matter. If I could tally a 'flow time' to mean the oil has reached 8 cSt (minimum acceptable viscosity).. then it doesn't really matter if it was the diesel that was the culprit.

Scientifically they are going to be able to tell me at the lab (when they retest) if diesel was the cause, as they use machine induced chromatography which will separate the diesel back out.

Life may be too short to bother however.. my main finding that matters is that the Range Rovers 'Service Required' indictator is in fact correct. Thats what I really wanted to know

 Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
--------------------------------------------------

DrRob wrote:

I’m a PhD level scientist and work in the oil industry around spill response and deal with viscosity changes etc all the time when oil and water interact. Take it from me, don’t waste your time and get it looked at as per previous posts is my advice
Air leaks are your enemy #1

Ah Rob, you're the same guy I've chatted to on Facebook with the dream job driving around on the Motor boat, lucky thing that you are

Yeah I am going to get the high pressure side of the turbo pipework tested. I am just looking to find a place or way to do so without breaking the bank. I emailed the company recommended on the other forum but they didn't provide a quote just said they would be happy to take it in for investigations. With workshop charges at north of 100 quid an hour these days I am not up for that sort of unbounded task!

My father in law is asking at his friends Landrover specialist workshop whether they have a high pressure smoke tester. If they do then I will get it tested when I am next in Devon, next month.

You are so very lucky to have Glenrands just up the road - I'd book it in without delay rather than waiting a month esp with the metalic contamination after just 3k miles. 2012 TDV8 Vogue (L322)

JayGee wrote:

From a scientific viewpoint.......;
There is no way to conclude there is any oil dilution and the only test shows no fuel in the oil
There is evidence of the oil being a lower viscosity than the label on the tin but that's not the same as saying it's diluted with fuel. Correlation is not the same as causation

Amazingly the lab do keep the samples for a period of time after giving the results back it seems (perhaps in case of complaints!). They have now tested my sample to establish the amount of diesel that was in it and found it to be less than 2%. So actually the viscosity change is potentially not because of the regens.

The RR must just be psychic in feeling it needs an oil change. I wonder what really thinned out the oil. Perhaps Westway oil is just stuff! I am really tempted to pay for a virgin sample to be tested, but I think that may be 'becoming obsessed'

Keep us posted and maybe meet in person soon  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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