After driving for hours while the engine oil is still hot or warm .But for most of us who don't travel outstation often , that's challenging and quite tough to sustain this practice .
I started off with 1.5 hour outstation travel habit but now settle at 25 - 30 minutes driving after work arriving home . Pick your 'sweet spot' , but generally do sampling after the longer hour traveling the better .
Yes, not first thing in the morning , or cold engine oil for more 'realistic' results .

Edit: Whatever time interval is selected , try to be consistent afterwards for realistic comparison of blotters .
Btw, I took blotter spot samples 10 - 20 minutes after engine shut down before it gets cold .

Hi dopamine ,

If you don't mind sharing here what are the two engine types and oil brand/grade types in question ?
Thanks for the 12 hour blotter spots , btw .

IME these blotter spot images would keep 'changing' and probably 'mature' after 48 hours or more  . After 48 hours the changes in the images  would likely not be obvious and drastic up to and beyond 96 or 120 hours .

It would be interesting if you could personally 'read' and 'study' the changing 'faces' of the images over 24/48/72/96 hour intervals (and share with readers here for educational purposes) .

My preliminary readings of these two 2400 and 3200 km usage oil blotter spots are that they are good with plenty of life to go on and it appears there is no signs of 'fuel dilution' in both samples as of now .

Oil sample for Car 2 is taken after 20 mins driving , would the 48 hour blotters shows fuel dilution (through observing transparent halo at the outermost zone) ? IDK .

Edit: Car 2 has only 2388 km after 11 months usage (June 2019) . Its 12 hour blotter as presented does not clearly shows fuel dilution problem yet , and  I would speculate its 48 hour blotter spot image is likely to show transparent halo at its outermost zone should this Car 2 engine actually encounters fuel dilution phenomenon .

Hi dopamine ,

A)Car 1 : 2014 Honda CRV 2.4L ,3200 km, 1.5 hour driving with M1 ESP 5W30 MB229.52
1)This blotter has a 2 mm thick halo around the diffusion zone (of about 60 mm OD size image) and at 1.5 hour driving , it indicates some fuel dilution problem here .
2)If this sample was taken 'cool' at say, less than 20 minutes driving (which was not) , then it is hard to say for sure about the fuel dilution problem .
3)The centre zone (of 8-10 mm OD actual of 30-35 mm size) is not darkened and opaque in colour indicating good dispersancy of ESP .
4)However this 3200 km blotter centre zone is relatively darker colour than that of Car 2 at 2388 km usage meaning there is higher level of combustion contaminants/dirt or wear particles .
5)The diffusion zone external to centre zone is quite clean and light in colour . Generally this ESP oil is still in good serviceable condition with plenty of life to go on .

B)Car 2 : 2007 Suzuki Swift 1.5L ,2388 km ,20 minutes driving with Syntium 3000 FR Ford 913D .
1)Despite low usage of 2388 km over almost 11 months duration and 20 minutes of minimal driving , this Syntium blotter has no signs of fuel dilution phenomenon . Personally ,I'm a little bit taken surprise here .
2)The centre zone is hardly formed and very transparent and light in colour and not grayish/darkish . This indicates very clean engine oil with superb detergency and dispersancy properties .
3)The diffusion zone and centre zone are very much more transparent and lighter in colour than that of Car 1 indicating this 11 month old oil is in good and serviceable condition with plenty of life left to further carry on .
4)This 11 month old oil is severely under-utilised at 2388 km usage . This should have theoretically given rise to more corrosion wear at prolong storage duration at cold oil temperature . But, the fact of the matter is the clean blotter spot image indicates this not being the case here . Hence I personally don't buy the idea or argument by oil companies/car OEMs that used engine oil cannot exceed 12 months usage (or worse ,some says 6 months) . This position of mine is further backed by multiple used oil analyses results of oils exceeding 12 months up to as much as 48 months usage in a sump . Please note also that Malaysia has no winter seasons like other users and our minimum ambient yearly temperature is 23/24*C  centigrade .

Yes , IMO you can continue using the 11 month old 2388 km Syntium 3000 FR oil in your Swift by comparing its blotter spot image with those  8000 - 15000 km blotter spots from Post #1 and evaluate for yourself .

This 72 hour blotter spot from Car 1, 2014 Honda CRV 2.4 L further reinforces the presence of fuel dilution phenomenon , despite after 1.5 hour driving .
Is this CRV 2.4L engine prone to fuel dilution ?Is the fuel system in proper order ?
Btw, is it a Direct Injection engine , anybody ?


I still believe this 72 hour blotter of 2007 Suzuki Swift 1.5L is free of fuel dilution issue .
Can you monitor this blotter further in days ahead whether a translucent halo at outermost zone surrounding the blotter spot would eventually emerge or occur ??
If yes, there may be fuel dilution though minor , otherwise there is none .

All other components of comments in my previous post remains valid in these two 72 hour blotter spots .

If your CRV 2.4L engine is not direct injection type , this fuel dilution issue after 1.5 hour driving is a bit abnormal IMO , although your low mileage of 3200 km over 5 months may promote fuel dilution as well .

Having said that , if your engine is Direct Injection type , then this fuel dilution problem is generally 'normal' .
Why I said 'normal' ?? That is due to the fact that some OEMs and all its SC's are not capable of resolving it and helpless in dealing with its fuel dilution phenomena  .
A case in point is the modern Honda 1.5L Direct Injection Turbo  (found in CRV and others) engine or typical Mazda carrying SkyActiv engine etc . Both OEM's are of international repute, and not national car of a Zimbabwee or Tongo .
Please search in Post #1 for a blotter spot of an Mazda engine indicating inherent fuel dilution phenomenon .

As per PM , fuel dilution problem has no relation at all with type or quality of engine oils in use .
It is strictly an indication of incomplete fuel combustion (and hence, loss of fuel efficiency ) and it has always been considered as undesirable and one issue to be eliminated by all car manufacturers for decades .
In short, it is an engine 'problem' .

As regards high levels of combustion contaminants/dirt and wear particles , it is a natural by-products of all engine operation and it increases with vehicle usage in terms of km traveled or engine hours .
There is where the practice of OEM recommendation of oil change intervals of 15,000 km or 10,000 km or 5,000 km comes in .

Can you continue using this oil ? Yes, as I had mentioned in my previous post . This ESP 5W30 is still in top shape and it has plenty of life to go on in your engine .

IMHO , by changing the engine oil earlier  say in your case of 3200 or even 5000 km , as is widely advised and practised  the mechanical life or longevity of this engine is not necessarily lengthened or extended or prolonged .

IMO, that is a complete myth !

Btw, I bought new and kept a car with carburretter engine up to 25 years long , and the engine in good working condition  . A carbutteter engine is typically prone to fuel dilution problem .

Hi Bro ,

This M1 ESP 5W30 is a mid-SaPS oil of rather powerful specs in ACEA C3 MB 229.51, 229.52 ; VW 50400 VW 50700 etc .

In Europe , OEMs' MB and VW recommend this oil for 30,000 km oil change intervals in appropriate MB/VW engines .

There is absence of darkened centre zone in this 7800 km used oil , which is good news .

There is also absence of darkened aureole zone/perimeter ring indicating absence of agglomeration of combustion contanminants and top form detergency and  dispersancy performance .

I consider the whole of diffusion zone as lightly contaminated with dirts with huge capacity for further absorbing additional amount of dirts during further usage .

Generally the amount of water moisture present is very mild and on the low side , judging by the not so obvious jagged external edge which is not darkened anyway  .

However , there is some slight indication of fuel dilution from the very slight translucent halo annulus external to the outermost zone which is harmless for now .

Overall , this used ESP is fit for further service IMHO beyond 7800 km  .