Hmm... I think the lab had your unit time incorrect. They list it as 5130 miles, with 2440 miles on the oil. Thanks for the clarification, I'll update the spreadsheet with this information. That means the analysis of your first change was significantly better than theFLASH's.

 

Yes, but I still think regardless of the similarity between block and piston, more fuel will get through because of aluminums' heat of expansion.Suggesting they made the piston&ring combination just a bit too small allowing an excessive amount of gap such that fuel can pass during warm up.


Later, Ken

 

Ken,

i dont have an evo X, i have a IX with all bolt ons nd Jestr tunned.

i will try to get some of those customers to chime in.

 

Heres the deal Kperez,,,, OILDOC does not build engines AMS does build engines David Buschur does build engines, Paul Nelson ECT ect ect...... if you ask any of these engine builders you will get almost the same answer.

i am not saying Bob (oildoc) is not knowegeable in this arena because he is he has been doing AMSOIL for longer than some of us have been living.

the fact is that when you build an engine you should go with the reccomended oil weight that builder reccomends.

like i said manny of my customers evox and evo8-9 are using this 20-50 but remember they pound on their cars like no one business.


i drive my IX everyday for fun and to go to work therfore i use 10-30 is all i need,,, however i still drive hard

 

I hear what you are saying but are these builders using heavier weighted oils to reduce fuel dilution or to counter the expected elevated temperatures from these modified engines?

Later, Ken

 

I pulled a sample yesterday of my ~2500 mile oil. Definitely smelled like fuel. I'll post when I get the results.

 

I received my results a couple days ago and...

...after EXACTLY (to the mile) 3000 miles I'm at 4.9% dilution by volume.

I'll post my Results Sheet when I can.

 

Hey guys, I am a former Mitsubishi owner, which is why I occasionally visit this site. I am also a daily visitor at the BITOG forums (bobistheoilguy): http://www.bobistheoilguy.com/forums/ubbthreads.php

That forum is dedicated to all things lubrication related. I have seen literally 100s of UOAs posted there, and cannot recall seeing any of them with fuel dilution as high as what is being reported in this thread. Fuel dilution of greater than 3% is highly unusual, from what I have seen at BITOG. Other motors prone to excessive fuel dilution are the Audi direct injected V8, the BMW twin turbo six, and the Mazda direct injected turbo 4. Fuel dilution under 1% is considered optimum.

One member of BITOG, who owned an Audi RS4 with the direct injected V8, was seeing fuel dilution between 2-3%, and elevated iron in his UOA reports. He went to considerable expense trying different oils, and doing multiple UOAs, obtaining the services of a tribologist, and finally settled on 5W40HD from Renewable Lubricants. This oil gave him reduced fuel dilution, reduced iron in the UOA, and longer change intervals. You can read more about it here:

http://www.bobistheoilguy.com/forums...893022&fpart=1

http://www.bobistheoilguy.com/forums...313219&fpart=1

If you want feedback from certified oil nuts, post your UOAs at BITOG forums, in the UOA section.

For readily available, OTC oils, Pennzoil Platinum is considered to be among the best at resisting damage from fuel, certainly better than M1.

If you are looking for more than just numbers on a UOA, I would recommend Dyson Analysis. They cost 4X more than Blackstone or Oil Analyzers ($99), but you will get a detailed audio report (along with a written report) explaining what the numbers actually mean, and you will get a credible and effective plan on how to reduce the fuel dilution. And they will recommend specific oils and fuel additives to combat fuel dilution.

I have used both Blackstone and Dyson. Blackstone is good for routine analysis on a well tuned motor, but when I started seeing elevated fuel (1.8%) and elevated bearing wear (high lead and tin) in my turbocharged Subaru Legacy, I went to Dyson for effective help.

 

Thanks Sub for the info. You have suggested some oil remedies, basically higher weight oil (as some others have done herein) and brand. I wonder in your passing through this issue have you found the sources of the excessive fuel dilution. For example, in the Bimmer V8 or Audi, did anyone investigate the source of the entry: rich A/F, injectors, etc and if so, could you provide same? Thanks.

Later, Ken

 

Interesting info on the BITOG forums. So they used a custom formulation of blended/mixed oils? I am weary of that, as not all additive packages are compatible, and mixing different oils is generally not recommended. Either way, even if a custom boutique oil works at reducing fuel dilution, it's still a band-aid and doesn't solve the problem at the source. I will personally continue to run amsoil, as I believe it to be the best oil on the market, and will just change it every 2k miles until this problem is solved. I hope someone can figure this out soon...

 

In the Audi V8 there was no mechanical remedy. Fuel dilution is inherent to the USA version of that motor. AFAIK, the same is true for the BMW twin turbo six. Below is an informative thread on the BMW. Pay particular attention to the comments from Terrry Dyson, such as:

".........RLI BIOSYN is the only oil I am seeing work well in DI RS4 or 2.0 Audi or the BMW bi turbo 3.0 I6 in the 335I. They both are killing every oil I used to recommend. I am not kidding and have no interest in promoting one oil over the other.

reb03, the M1 0w40 should not be run longer than 1000 miles to be safe.. Audi and BMW know they are having problems but are marketing tied to certain LARGE oil company that sponsors BITOG thus they cannot speak out about it.

GC 0w30 green might work well here but the fuels chemistries have changed so much that it may be out of date to protect as well as I would want to see.

I asked the BMW 335i customer to post his Dyson raw data here and chime in, whether he is crazy enough to do that I can't say. The raw trended data will scare you straight................."

http://www.bobistheoilguy.com/forums...981168&fpart=1

In my Subaru I ended up replacing all four injectors, at 17,000 miles, on my 100% stock motor. My last UOA from Dyson showed greatly reduced bearing wear, and my fuel was down to 1.0%

 

It is a custom formulated oil, but not a mix of different oils.

http://www.RenewableLube.com/pdf/Bio...otor%20Oil.pdf

Yes, I agree whatever oil you use, it is a band aid, and does not address the cause of the fuel dilution. But if the cause can not be remedied, then you will need a good band aid.

 

Here is a link on how flash point is used to determine fuel dilution:

http://www.oilanalysis.com/article_d...up=Maintenance

And here are two links to help you understand UOAs:

http://www.oilanalysis.com/article_d...up=OilAnalysis

http://www.oilanalysis.com/article_d...up=OilAnalysis

 

Your wear pattern looks a lot like that on the Audi V8. Elevated iron at 35ppm, indicating increased wear on camshafts, timing chain, etc . Bearing wear is surprisingly low, they must be made out of kryptonite. Your oil has sheared down to a 5W20.

And nitration is definitely high. In my Subaru I am seeing nitration at 7-8. From one of the links I posted: "........As with sulfation, nitration is the reaction of the oil with combustion by-products of nitrogen. These reactions tend to become more pronounced at higher temperatures. Therefore, increased nitration is often an indication of increased blow-by, as the hot combustion gases react with the oil........"

And fuel dilution of 4.7% is sky high, IMO, for a modern fuel injected motor. Did you get your oil nice and hot before taking the sample?

 

Here's my report, I've blacked out my personal information AND the 'DATE SAMPLED', 'UNIT TIME' and 'LUBE TIME' fields as they were erroneous.

The correct numbers are:

UNIT TIME: 7035 miles
LUBE TIME: 3000 miles