Fuel Dilution - DI Engines

[Tjbouwhu]

Lots of debate on DI engine fuel dilution, and "thin" 0W20 oils. Attach is a technical bulliten from Polaris Labs on the subject...interesting read.

https://polarislabs.com/how-gasoline-engine-technology-affects-fuel-dilution\

I am not sure I did this link correctly? Guess I'll find out when I hit the post button!

 

[SteveSRT8]

Only thing is despite endless discussions there have been virtually no cases of engine damage conclusively linked to it.

 

[oil_film_movies]

This is basically what many of us have been saying to do about it: Polaris says to: "If the wear metals are increasing and the viscosity is decreasing, reducing the
interval time or increasing the viscosity of the oil may be recommended. " --- I generally say just go up a viscosity since some people might not want to chang their oil weekly....
https://polarislabs.com/how-gasoline-engine-technology-affects-fuel-dilution/
That last slash was pointed the wrong way in the link above.

 

[PimTac]

I wonder how today's fuel dilution numbers would compare to the old days of carburetor fed engines? Back then the oil was not as advanced as today either.

 

[JohnnyJohnson]

When are they going to design FI that isn't CXXP?

 

[skyactiv]

Originally Posted by JohnnyJohnson
When are they going to design FI that isn't CRAP?

Fixed it for you!

 

[Audios]

One of my friends at a BMW dealer near me says theyre looking into the 0/20 they recently switched to, especially on their turbo models. Lots of crankshafts wobbling. There was a thread on reddit and the dealers are blaming the techs after changing out the oil filter housing seals, some are saying 10-15k later. My friend was saying theres a huge occurance of failure 15-20k after switching to the 0/20 in 2017, all dealer maintained.

https://www.reddit.com/r/BmwTech/co...ter_housing/?st=JSM7XLM3&sh=8125676d

 

[littlehulkster]

Originally Posted by skyactiv
Originally Posted by JohnnyJohnson
When are they going to design FI that isn't CRAP?

Fixed it for you!


You must not have ever owned a carbureted car. Carbs are absolute junk, and always will be. I'd take the worst EFI system ever designed over the best carbs. Unless, of course, you like constantly messing with your car but never getting it to really run right, or you love the feeling of never knowing if it's going to start or not.

EFI is the best thing on modern cars. It just works. Way more efficient than carbs, too.

 

[ChrisD46]

*True story - I change the oil in my older PFI engines in the garage after a 6K OCI and my wife smells nothing inside the house ... I change the oil in my 2017 GDI Sonata in the garage with the garage door open after a 4K OCI and she comes flying out asking : "Did you spill gasoline ? - You can smell it in the kitchen and dining room now ! "

 

[PimTac]

Originally Posted by Audios
One of my friends at a BMW dealer near me says theyre looking into the 0/20 they recently switched to, especially on their turbo models. Lots of crankshafts wobbling. There was a thread on reddit and the dealers are blaming the techs after changing out the oil filter housing seals, some are saying 10-15k later. My friend was saying theres a huge occurance of failure 15-20k after switching to the 0/20 in 2017, all dealer maintained.

https://www.reddit.com/r/BmwTech/co...ter_housing/?st=JSM7XLM3&sh=8125676d




It must be true, it's on the interweb.

Wobbly crankshafts due to 0w20? My guess is that this is a BMW issue more than it is the oil.

 

[oil_film_movies]

Originally Posted by PimTac
Originally Posted by Audios
https://www.reddit.com/r/BmwTech/co...ter_housing/?st=JSM7XLM3&sh=8125676d
It must be true, it's on the interweb.
Wobbly crankshafts due to 0w20? My guess is that this is a BMW issue more than it is the oil.
That one is interesting. Basically they are saying the abrasive particles in Scotchbrite or similar scouring pads, which has nothing to do with 0w20 usage, are getting to the crank bearings after an oil change tech cleans under the o-ring before changing it. I suppose that is possible. Interwebs === truth.

 

[MCompact]

Originally Posted by SteveSRT8
Only thing is despite endless discussions there have been virtually no cases of engine damage conclusively linked to it.


Who needs facts when we've got hundreds of unsubstantiated rumors?

 

[ZeeOSix]

So the Polaris article said: "Most OEMs are using low viscosity oils that tend to be more tolerant of higher amounts of fuel."

What's the technical explanation if that's really true?

 

[ZeeOSix]

Polaris also said:

"Now, the fuel is directly sprayed into the combustion chamber under extremely high pressures, in most cases in excess of 2200 psi. This has allowed for much greater control to allow a more precise combustion process, making the engines more fuel efficient and creating more power with smaller displacement engines."

"With direct injection the fuel is being sprayed directly into the cylinder allowing larger droplets of fuel to come into contact with the oil coating, washing down the cylinder walls. This leads to higher amounts of unburned fuel in the crankcase, showing higher fuel dilution on your reports."

So how do DI engines get better gas mileage if they are causing more wasted (unburned) fuel going past the rings and diluting the oil more?

 

[y_p_w]

Originally Posted by ZeeOSix

So how do DI engines get better gas mileage if they are causing more wasted (unburned) fuel going past the rings and diluting the oil more?

Likely a small amount relative to the boost in efficiency.

 

[wemay]

Originally Posted by MCompact
Originally Posted by SteveSRT8
Only thing is despite endless discussions there have been virtually no cases of engine damage conclusively linked to it.


Who needs facts when we've got hundreds of unsubstantiated rumors?


...and, as has been said before, the fact is the vast majority... VAST ...of UOA lack elevated wear numbers, even with substantial dilution.

I'm not concerned as i'm currently running a 0W20 (Pennzoil Platinum) in the Sportage 2.4L and thus far (4th day) it's been extremely smooth and quiet. And yes, i have an email from the Service Mgr of one of the local KIA dealerships that says it's perfectly fine to do so because the important number is the 20, not the 5w vs 0w.
My OCI are 5K max.

 

[BMWTurboDzl]

Originally Posted by Audios
One of my friends at a BMW dealer near me says theyre looking into the 0/20 they recently switched to, especially on their turbo models. Lots of crankshafts wobbling. There was a thread on reddit and the dealers are blaming the techs after changing out the oil filter housing seals, some are saying 10-15k later. My friend was saying theres a huge occurance of failure 15-20k after switching to the 0/20 in 2017, all dealer maintained.

https://www.reddit.com/r/BmwTech/co...ter_housing/?st=JSM7XLM3&sh=8125676d



Ya it's not the oil. The bearing issues are also occurring on older models which have the same engine (N55) and also had the OFHG changed.

 

[wemay]

Quote
How much is acceptable?
While OEMs do not publish acceptable numbers, the common range used by most is that 3-
7% can be acceptable as long as there is not a noticeable increase in wear or drop in lubricant
viscosity. Most OEMs are using low viscosity oils that tend to be more tolerant of higher
amounts of fuel.

 

[BigShug681]

Originally Posted by wemay
Quote
How much is acceptable?
While OEMs do not publish acceptable numbers, the common range used by most is that 3-
7% can be acceptable as long as there is not a noticeable increase in wear or drop in lubricant
viscosity. Most OEMs are using low viscosity oils that tend to be more tolerant of higher
amounts of fuel.

So you mean fuel dilution doesn't automatically mean rebuilding the engine?

 

[dave1251]

No it does not and we are talking large amounts of fuel before it affects wear a lot more then we are seeing with DI UOA's.