R56 First oil change...

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Nov 11, 2007 | 09:05 AM

#126

Robin Casady

6th Gear

Joined: Mar 2007

Posts: 7,578

Likes: 4

From: Paradise

Thanks. I look forward to your next report in January.

Nov 11, 2007 | 09:47 AM

#127

jascooper

5th Gear

Joined: May 2007

Posts: 742

Likes: 0

From: Coopersburg (really), PA

Quote:

Originally Posted by ScottRiqui

Well, I looked at the results of the analysis on the factory-fill oil, when I still had the stock airbox and filter. That oil was in the crankcase for 12,500 miles, and had similar Total Acid, Total Base, and fuel dilution numbers. Not totally spent, but definitely near its end-of-life.

For that first analysis, Terry thought the fuel dilution might have been because of the engine break-in, but it's still there, even though the current oil wasn't put into the car until 12,500 miles. I really wish I could see analyses from other MINIs, just to see what the typical dilution percentages are on other peoples' cars.

As for the oil that Terry recommended, it's Biosyn 5W-30, by RLI (Renewable Lubricants, Incorporated). He actually recommended their 0W-30, but I ordered the 5W-30 by mistake. Terry said that their 5W-30 is fine as well, and if we get good numbers using it, there's no reason why I couldn't stick with it.

Can you explain for us neophytes what fuel dilution is? Is that gas getting into the oil? Past the rings? Or what?

Thanks, and thanks for sharing the results of your report,

Nov 11, 2007 | 10:10 AM

#128

ScottRiqui

OVERDRIVE

Joined: Aug 2006

Posts: 7,201

Likes: 8

From: Norfolk, VA

Quote:

Originally Posted by jascooper

Can you explain for us neophytes what fuel dilution is? Is that gas getting into the oil? Past the rings? Or what?

Thanks, and thanks for sharing the results of your report,

That's exactly it - gas getting into the oil. Some level of fuel dilution is unavoidable, and the 1.2%-1.5% numbers I've been getting aren't necessarily a sign that something's *wrong*, but lower is obviously better. That's why I'd like to find out what other people have been getting for fuel dilution in their analyses. Also, some oils do a better job of sealing off the gap between the piston rings and cylinder walls, so it's possible to get different dilution numbers depending on what oil you're using.

Here's a site that talks about oil analysis results and what the various numbers mean. It's very general, and is no substitute for having an experienced tribologist analyze the lab results, but it'll give you an idea of what they're looking for.

Nov 11, 2007 | 11:28 AM

#129

johne123

3rd Gear

Joined: May 2007

Posts: 232

Likes: 6

thanks!

Thanks for the info on your oil analysis. I'm just over 2k miles on my car. Plan to do an oil analysis at 5k and then as needed.

Nov 11, 2007 | 03:00 PM

#130

ekailee

2nd Gear

Joined: Nov 2007

Posts: 87

Likes: 0

From: So Ca

I just changed my oil at 1200. Cost me Ramp $35, 27mm socket $5, filter $8, drain pan $11, total $59. (son-in-law works at BMW so I the filter cheap and free Oil). It took 1 hour and I took my time!! I will be doing it at each 7500 miles.
Here's the deal. with all that i'm reading I'll do what make me feel good. Yeah it runs hot, turbo, I drive hard, how can you not? So I'll take care of Winston.