Hi Gene... well thought out replies, indeed. Just for some final
clarification, here are some things I can say to back up my statements.

I didn't say AV-1 didn't damage cam lobes or tappets... what I did say
was that wasn't the only problem _in particular_, but that AV-1
apparently caused even bigger damage in areas not under direct constant
pressure. There are still different opinions as to what actually was
the problem with AV-1 (Mobile Oil won't say...but I think they know.)

As for Mobile AV-1 being "100% synthetic"... yes, that's what Mobile
Oil advertised. However, while Mobile AV-1 and Mobile-1 (pre-1992) said
they were "100% synthetic", that was with an asterisk: "*exclusive of
carrier oil." They indeed had, by Mobile oil's own admission up to 19%
petroleum-based a"carrier oil." 81% synthetic ain't 100%, even 95%
isn't (not in my book anyway.) 100% is 100%, right?

Now if I remember right, AMSOil was challenged by Mobile oil when
AMSOil claimed Mobile-1 wasn't "really 100% synthetic" ... well the
upshot of that conflict was that Mobile Oil withdrew the legal
challenge and changed their formula to eliminate petroleum-based
additives, thus making it truly a "100% synthetic lubricant" (as of
1992 sometime.) I also remember the FTC being involved.

Notably, neither SAE or API have a clear definition for what
"synthetic" oil is. Some say it is simply a marketing term. I go by my
own experience, results, some of what I hear from people I know and
trust and my gut.

I would suggest you try ONE oil change with AMSOil Formula 4 or Red
Line Racing Oil. Pay attention to temperature readings, top speed and
overall smoothness of idle. Maybe it's all in my head, but I sure think
it makes a difference that I could tell right away. I would not
recommend Mobile-1 anywhere except in your personal automobile engine.
If you had 2-stroker smokers as I do, I would recommend either the
AMSOil Saber Outboard or Red Line's Watercraft Oil.

Finally, I agree with you about AMSOil's advertised API tests... they
show what they want you to see. I wouldn't put my faith in what any
website says, rather see what works for you.

Give it a try... just not in your aircraft engine. Yet.

Jeff



Gene Kearns wrote:
On 6 Jun 2006 15:29:34 -0700, Chehalis Jeff penned the following well
considered thoughts to the readers of rec.boats:

As a pilot and previous aircraft owner (1969 Beechcraft A36) I am well
aware of the Mobile AV-1 debacle. The problem with AV-1 was apparently
a chemical compatibility problem that only applied to AV-1 that caused
sludge buildup, thereby drastically reducing the oil's ability to
lubricate. In cases where AV-1 caused damage, it had little to do with
tappets or cam bearing surfaces in particular, it was spun crank
bearings, cylinder wall damage - big problems.
It had plenty to do with tappets and cams...
http://www.eaa49.av.org/techart/mobil01.htm

If you recall, Mobile-1
(and Mobile AV-1) wasn't a fully synthetic oil in their first
formulations.
Mobil AV-1 WAS a fully synthetic oil. "Mobil introduced its 100%
synthetic AV-1 piston aircraft engine oil with great ballyhoo in
connection with the 1986 round-the-world Voyager flight. It went on
the market in 1987, after five years of R&D and 25,000 hours of flight
testing in 23 different aircraft.. " See:
http://www.avweb.com/news/news/182891-1.html


Mobile-1 is a different animal now and is fully
synthetic.

And isn't approved for use in aircraft... though I do admit it is a
different animal and is my oil of choice in land based vehicles. I'm
seriously considering using it in my outboards after the warranty
period.


I would think if the same problem(s) existed in Mobile-1 or any other
synthetic oil, they would be pulled off the market or the manufacturers
would be sued (like the AV-1 issue) or both. I haven't seen that
happen, in fact more and more major oil companies are formulating
better and better synthetics, all of which outperform mineral/petroleum
oils.
Well, the proof of this is that there are no fully synthetic oils on
the aviation market.... only semi-synthetic.


I don't have anything against Mobile-1 or any other fully synthetic
major brand, however I choose to use only AMSOil or RedLine Synthetics.
The API tests speak for themselves.


I remain skeptic with respect to the selectivity of the AMSOil API
tests.

--

Grady-White Gulfstream, out of Oak Island, NC.

Homepage
http://myworkshop.idleplay.net/

Rec.boats at Lee Yeaton's Bayguide
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