KPerez

Ok, time to get out the heavy guns; sent below to Eric at AMS today:

Eric et al.,
I know you guys read the EVOM forum often and may have run across the issue of excessive fuel entering the engine oil of the X (please see https://www.evolutionm.net/forums/ev...l-problem.html). While we have not acquired sufficient numbers, what we have seen to date in OEM "tuned" and aftermarket tuned engines is >4% fuel dilution which at best has been defined from testing labs as "critical levels; Oil Doc (Rob) claims anything over 2% is unacceptable; more results from other cars will be coming in from outside independent oil testing firms.

At first thought everyone pointed to the rediculously low A/F under load. It was felt that when an aftermarket tune was installed resulting in A/F going from 9's to 11's that we would see reductions in fuel dilution to <2%. However, for the one case we have (StevX) this did not occur; he got >4% with 3.3K mi between oil changes.

Now the questions: Has AMS observed excessive amounts of fuel in the engine oil of the 4B11? Is this concentration a concern from an engine longevity point of view? If the answer is yes, then there are a lot of worried X owners out there that want this problem resolved. Since AMS has ripped this engine completely apart, we would all appreciate your input as to the potential causes for this excessive fuel entry. Thanking you in advance from a lot of nail biting EVO X owners!

Later, Ken

Papi4baby

iTrader: (1)

I dont think you understoof my post or i didn't explain it well enought. I was not talking about normal detonation. But internal( lower engine, where the crank and piston rods are) detonation from fumes and preassure built up.

And i think you are also misinformed. You can't just go by one sample. You have to establish a trend when you have an issue like this. And keep and eye, make sure that the metals count does not increase. If the metal count stays the same, then there's no problem. But once you see a spike, something is going wrong. And like i said a while ago, we have no idea what the limits or standards are for the 4B11 on wear metals. And that's some of my doubt too. The fuel dilution level you guys are seening might be normal for this engine, and might not be too big of and issue. Now i am not saying is not, but just something to keep in mind, before we go knocking on Mitsubishi door.

I sure can't wait till someone gets to talk to, or some info from a Mitsubishi engine engineer on this issue.

I did oil analisys when i was in the Navy. I know a little bit about the process. Granted it does not apply to cars, but it is somewhat similar.

Drew84

^ You sir have got the right idea, we all need to gather our data and put it together to get an accurate sample of 4B11 engines. It would be interesting to see the results from a Ralliart Lancer too. This is going to take some months because most of the cars need miles to be put on them. Patience is the key. Look at it this way, when the FDA does drug testing that can take up to 10 years to find the effects of it. I'm not saying this will take this long, but case studies like this are pretty involved.

Papi4baby

iTrader: (1)

Hate to be pessimistic. But that is going to be hard.

And even then, the results would be skew one way or another. From people using different oils, to different fuels, and different driving patterns.

Would be nice, but nearly impossible. The best thing if you are truly worry about it, and dont mind spending 25 bucks a month is to keep on doing oil samples, and hope nothing bad happens.

STi2EvoX

Papi, I am not misinformed about anything. I am not basing my opinions on someone else's sample, I am basing it on MY sample (remember I was the first one to do the analysis) and what I know about the effects of fuel dilution. You need to realize that it has nothing to do with engine design; it is based solely on the known properties of oil and the subsequent effects of fuel when they are mixed. There is no engine that "tolerates" fuel dilution more than another, because engines all rely on oil, and when oil fails, engines fail. Fuel causes oil to fail. Period.

So, you need to get this, "we don't know what the standards are for the 4b11, this might be normal" crap out of your head because it doesn't work like that. Now look, I spoke in great detail with one of the lab techs about this yesterday, and this is what he had to say: When there is 4-6% fuel dilution, oil can drop up to 2 grades, effectively taking a 30W oil down to a 20W and lower.

When viscocity decreases, there is less of a cushion surrounding the particulates, like dust, that get past the air filter and into the oil. These particulates will start to grind against metal components, increasing wear metals. Fuel also eats bearings once it gets around the 5% mark. Once fuel dilution passes this point, oil will rapidly start to break down at exponential rates and engine failure will occur. These are things that are undisputable, so I think you might want to rethink how you look at the issue because this is going to bite you in the *** if you ignore it.

To stevx: the reason that your nitration levels are high is possibly because you are running too lean, according to the lab tech. When you are running too lean, combustion temps rise, obviously. When temps get high enough, you can actually burn the nitrogen in the air, which effectively deposits itself as nitric acid. As nitric acid passes by the rings, nitration levels go up. High nitration levels lower you TBN (total base number), which is the measure of an oil's ability to maintain correct Ph balance and neutralize acids in the oil. It is worth considering that if you are running lean and still getting fuel dilution, then there is most likely a mechanical issue with the car somewhere.

Judging by the fact that our fuel dilution levels are pretty similar, we probably both have the problem, along with many others. I personally believe this to be a widespread issue, but we will know more when more analysis reports start coming back.

Papi4baby

iTrader: (1)

Ok.

theFLASH12

Gizmo, thanks for the spreadsheet, I'll be having some inputs soon also. My Oil Analyzers report of my first 1009 miles s/b available next week, the following will be another 1000 miles, then I'll get my APtune, after whichat the 3000 mile mark we'll have more data.

All this info you have all laid out has gotten me pretty anxious..

Noize

iTrader: (24)

I'm rethinking my stance on this. I do think we should be vigilant, but I don't think we can jump to conclusions with only a couple analysis results.

Mad_SB

iTrader: (8)

I should have two sets of results in a couple months one set from blackstone and one set from oil analysis or whatever the name of the one amsoil uses is. Both will be from the same sample so this should also help us make a comparison between the two companies.

KPerez

Yes Mad, Interlab comparisons will provide a measure of the variability we can expect when we get submissions from individuals using different labs for the analysis of their oil. Good QA/QC move here.

Later, Ken

Papi4baby

iTrader: (1)

Just put gas and check the oil. And this time i can smell fuel. Oil change is coming up this week.

KPerez

Ok, Called AMS yesterday regarding above letter to Eric and got a hold of Dan. He had looked at this thread earlier and really could not provide any causes for excessive fuel additions. He did, however, comment that the oil weights used by some, namely 0-30 and even the OEM recommended 5-30 was a bit low. Recommended 10-40W instead and retest to see if %fuel dilution was improved i.e., lowered. This may be a better interim "solution" since the fuel addition is reducing the viscosity, so increasing weight will add a bit of cushion.
For me, after this weather lifts, I will test OEM 5-30W already in my car and then replace with 10-40W and retest at next oil change to see if %fuel is lowered; this will be sometime down the road though. As you are all aware, to get to the bottom of this, it will take time, envolvement of EVO X owners and patience.

BTW, Dan indicated that Mitsu is definitely reading EVOM. How did he know this, I asked? When AMS went to corporate last year, Mitsu rep's indicated they were pleased with the performance results of the 4B11 that AMS had posted earlier on EVOM. Bottom Line: Our concerns are perhaps being observed but would like a more direct communique, like a formal letter requesting their assistance in establising the existence of the problem, its causes and possible solutions. So MItsu, if you are out there, how about stepping up and be counted on this issue? To do such is in all our interests.

Later, Ken

Mad_SB

iTrader: (8)

I mentioned using a heavier weight oil in the summer months last time I was at the dealer (getting the good old oil leak from behind the water pump fixed) and was told NOT to change weight because it can play hell on the mivec....

They claimed they had a regular lancer in that just would not run right come to find out it had the wrong weight oil in it and when they swapped it back to the proper weight mobile 1 it ran like a top.

Personally, I would tend to think it was just overfilled, but I don't know. Just food for thought.

KPerez

Yes Mad 8, you did suggest this earlier and I to think the dealership is way off about changing weights; I think AMS has a little more experience and their statement suggests the lighter weight OEM oil (5-30)may be allowing more fuel to enter through the rings.

Later, Ken

apagan01

iTrader: (299)

exactly what i have been trying to say for some time now, the way we drive these cars the amount of heat we put into the engines by driving hard the car needs that extra viscocity to.

manny shops not only AMS has said this for some time now.

i have Evo9 and EvoX customer both cars using 20-50 you may think is way to think but with 30psi and race gas and or meth is really peace of mind.