The Mobil AV-1 story

Jimbo · Mar 5, 2003

I'm going to link to it rather than paste excerpts here so as not to violate copyright and so you can read the whole thing.

www.avweb.com/news/news/182891-1.html

www.avweb.com/news/news/182892-1.html

www.avweb.com/news/news/182893-1.html

Pablo · Mar 5, 2003

Thanks for the post. THAT answered a LOT of questions.

Although I'm in no way connected with the aviation industry - from time to time a when I'm talking with a potential customer - a customer who is a pilot (but only stuff for his car)- I get: "It was you guys that sold that bad oil...." I try to assure him that Amsoil does not sell Aviation oils....but I never knew this may lay at the heart of this issue.

GeorgeCLS · Mar 19, 2003

Please don't look at the links as the complete "rest of the story" regarding Mobil AV-1. I have 2,000 hours of trouble free hours use of Mobil AV-1 in a helicpter engine which prior to switching to AV-1 would toast a turbocharger every 200 to 500 hours. And another operation which accumulated a total of 18,000 hours operation without a single engine removal or component failure prior to normal TBO.
And then the story of my good friend who had to wait to pick up his brand new Beech Baron because the brand new engines were removed due to cylinder/ring problems: this was a year ago.. i.e. the same problem nature of ring/land/cylinder problems that Mobil AV-1 was blamed for causing...
Bottom Line: yes, Mobil AV-1 may have had operational problems in certain engines, but there were many applications where Mobil AV-1 eliminated problems...

Jimbo · Mar 20, 2003

Since you are a distributor for Exxon Elite, I assume that you use the product. Is your turbocharger still burning up every 200 to 500 hours with a synthetic blend?

Cylinder jugs on big-bore Continentals are not known for lasting to TBO, that's true. It does not explain the problems some had with crankcase, governor and prop hub sludge. Blaming the customer for the problem is a favorite tactic in the aviation business that would not be tolerated in the automotive world today.

I think the basic issue is the lack of natural solvency for PAO. Since ashless oils cannot have the robust additive packages of car and truck oils, there lies the problem. Blends solve that problem.

Bror Jace · Mar 20, 2003

Jimbo: "I think the basic issue is the lack of natural solvency for PAO."

That's what I understood as well. PAOs (at the time) had no ability to scavenge lead and that was the primary cause for the build-up of that grey sludge described.

--- Bror Jace

GeorgeCLS · Mar 21, 2003

Regarding the use of the Aviation Elite. Unfortunately I no longer am flying the helicopter which used the Mobil AV-1.. And yes, the Aviation Elite is really doing well operationally. We have one fleet that has ammased over 20,000+ hours with Exxon Elite and it has eliminated many of the problems that were prevalent with the previous oils used.
Regarding the comment "blaming the customer". How about blaming the engine?? If AV-1 was so inferior, how did it work so wonderfully in Lycoming engines?? AV-1 performed wonderfully, especially in severe applications such as helicopter usage. Sticking exhaust valves in IO-360 engines became a thing of the past with AV-1. But no one talks about the Hughes 300 that was running Brand X semi-synthetic and ended up crashing with the 3rd stuck exhaust valve in 2 weeks; after switching from AV-1 in which the engine ran over 1,000 hours without one stuck exhaust valve.. The pilot did not walk away......
Prop dome sludging was not exclusive with only AV-1 but very much related to: IO-520's/55's, operational methods, etc.. There were many IO-520/550 fleets which ran to TBO with no sludging, no buildup.. That was the confounding aspect of the AV-1 story..
George

pmt · Jan 16, 2004

Two or three years ago I recall stumbling onto a website that covered (supposedly) the technical reasons for the Mobil 1 AV-1 problems. As I remember, the leaded fuel/sludging situation caused the most grief.
But the site article also mentioned that in an engine that sits for several months without running, like many aircraft engines, synthetic oil is not the best choice since it does not coat engine parts as well as dino oil and during long periods of inactivity the parts will rust. And that was also a big problem in the use of Mobil 1 AV-1 in those aircraft engines. Unfortunately I didn't bookmark the site.
I don't own an airplane, but I do have a car that sits 4-5 months during the winter. I have used M1 5W-30 and also Delvac 1.
So I have two questions: 1) Does anyone remember the website article I'm referring to? 2) Would I be better off having dino oil in my car's engine during the winter months when it is sitting?
Thanks in advance for any help.

MolaKule · Jan 16, 2004

If you are going to store a car, use an HDD like Delvac 5W40 or Amsoil 15W40 AME, or Schaeffer's #700.

Diesel oils have slightly higher levels of Rust Inhibitors, anti-oxidants, and metal deactivators to protect internals against rust and corrosion.

Use fresh oil before storage and make sure new oil thoroughly circulates through engine.

Shannow · Jan 16, 2004

There's a Castrol farm/fleet oil available down under that has additional Vapour Phase Inhibitors in it that may help with storage.

Molakule, have you got much information on the couple hundred year old European tradition of placing a piece of camphor in a gun cabinet as a VPI ?

Was wondering how a bag of the stuff on a string would go at protecting engines in storage.

Jimbo · Jan 18, 2004

Understand that aviation oils are "ashless". This means that they do not have the conventional additive packs of car and truck oils that include calcium and/or magnesium salts to neutralize acids. Aeroshell does have a special "preservative" oil for aircraft engine storage, but it is only recommended for very limited running use. Because of this issue, the major engine rebuilders do not recommend any multi-grade oils for infrequently flown aircraft. The reasoning is that straight grades do not drain off of internal parts as easily, providing better rust protection.

pmt · Jan 19, 2004

quote:

Originally posted by MolaKule:
If you are going to store a car, use an HDD like Delvac 5W40 or Amsoil 15W40 AME, or Schaeffer's #700.

Diesel oils have slightly higher levels of Rust Inhibitors, anti-oxidants, and metal deactivators to protect internals against rust and corrosion.

Use fresh oil before storage and make sure new oil thoroughly circulates through engine.

I understand the rationale behind your suggestions. But is there any evidence that synthetic oils drain off engine parts more readily the dino oils? I'm pretty sure the article on M1 AV-1 oil that I saw (and didn't bookmark) mentioned that is what caused rust in aircraft engines using M1 AV-1, that sat for several months without running.
Thanks.

pmt · Jan 19, 2004

quote:

Originally posted by Jimbo:
Understand that aviation oils are "ashless". This means that they do not have the conventional additive packs of car and truck oils that include calcium and/or magnesium salts to neutralize acids. Aeroshell does have a special "preservative" oil for aircraft engine storage, but it is only recommended for very limited running use. Because of this issue, the major engine rebuilders do not recommend any multi-grade oils for infrequently flown aircraft. The reasoning is that straight grades do not drain off of internal parts as easily, providing better rust protection.

So the Mobil 1 AV-1 oil that caused all the trouble back a few years ago probably didn't have much in the way of anti corrosion additives in it? Also, I don't understand why a multi-grade oil, say a 10W-30, would drain off engine parts any worse than a SAE 30 - if the engine is shut down hot, the viscositys of the two oils would be pretty similar. Unless there is some other difference I'm not aware of.
Thanks.

jthorner · Jan 23, 2004

Not being in aviation, this is the first time I have heard about this story. Now that I have read many of the articles on it I am shocked at the attitude Mobil took throughout the whole matter.

Anyone can make a mistake, and it seems clear that AV-1 should never have been released for general use. Sure it worked great in many applications, but it was not marketed as only being suited to certain applications.

Once the mistake was known, Mobil should have stood up proactively to make good as much as possible on the problems they had caused. Instead they took the greedy lawyer/MBA view and did everything possible to minimize their costs while saying the **** with those who got burned.

The difference between honorable people and scum is often in how they deal with the aftermath of their own mistakes, and Mobil certainly seems to have failed the test.

John

Shannow · Mar 27, 2004

, but the same company.

We had the entire piston engined fleet grounded for considerable time downunder due to a fuel conatmination crisis.

http://www.atsb.gov.au/aviation/editorial/fuel_contam.cfm

StanW · Oct 24, 2004

Mobil AV-1 like Amsoil AVOIL was only approved only in certain engines and were great products, but there were idiots who did not read the instructions and they are principally the ones who had problems. Both oils were non-detergent/dispersent oils just like their conventional couterparts. To this day Shell still sells a synthetic blend.
The reason both the Mobil and Amsoil products were pulled off the market was the cost of liability insurance in relationship to the small amount of oil sold, not because they were bad products.
As some of you probably know synthetic oil is the only lubricants use in jet aircraft which is a totally different creature and Exxon/Mobil is the leading manufacturer of those products.

Mickey_M · Oct 24, 2004

quote:

Originally posted by StanW:
Mobil AV-1 like Amsoil AVOIL was only approved only in certain engines and were great products, but there were idiots who did not read the instructions and they are principally the ones who had problems. Both oils were non-detergent/dispersent oils just like their conventional couterparts. To this day Shell still sells a synthetic blend.
The reason both the Mobil and Amsoil products were pulled off the market was the cost of liability insurance in relationship to the small amount of oil sold, not because they were bad products.
As some of you probably know synthetic oil is the only lubricants use in jet aircraft which is a totally different creature and Exxon/Mobil is the leading manufacturer of those products.

Had Mobil labeled it for use in certain engines, there would have been no problem. Engines with a lot of blowby using AVgas (high lead) were not within the design parameters of the oil.

It was such a blow to Mobil and its reputation that the current premium aviation oil is an Exxon branded product, not Mobil.

This is a good example of where chemistry and the laboratory end and the field tests should begin. No matter how bright the formulater, if you don't understand completely what the conditions of use will be, both theoretical and practical, you're eventually going to experience a design failure.

StanW · Oct 27, 2004

Mickry_M, Here is what is says on a bottle of AV 1.
Fully compatible with any approved aviation oil
Mobil AV 1 is compatible and can be with Lycoming LW106702 additive per FAA AD80-0403, however, Mobil recommends no engine oil supplements or additives be used.
For nre engines, before usingf Mobil AV1, see engine builder's instructions,
When changing from any other engine oil, follow engine builder's instructions.
Mobil AV 1 is STC'd for 200 hour oil changes in engines with oil filters. Follow engine builder's instructions for oil changes.
Approved by thef FAA
9STC No. SE452NE) and excedes the requirement of MIL-L22851C,Teledyne Continental Motor Spec.MHS25 an MHS 24C, and AVCO Lycoming Spec. 301F Not certified for radial engines.
How many people do you think followed these instructions or just dumped this into their engines with or witout a filter.

Mickey_M · Oct 27, 2004

quote:

Originally posted by StanW:
How many people do you think followed these instructions or just dumped this into their engines with or witout a filter.

The problem with the Mobil AV-1 was, simply, an inability to deal with lead from av gas blowby.

Here are some urls that help put it in perspective (some of them contain minor spelling and factual errors):

http://www.eaa49.av.org/techart/mobil01.htm

http://www.avweb.com/news/news/182891-1.html

http://www.prime-mover.org/Engines/Lycoming/sbslsi_index.html

S.L. L229A Lubricating Oil, Use of Mobil AV 1 Synthetic, in Textron Lycoming Reciprocating Engines

The problem was lead and AV-1's limited ability to deal with it. Combined with extended drain intervals, infrequent operation, and disregard of warning signs, it could result in serious engine damage. This happened with engines that used no other oil but AV-1 from purchase (Continental Voyagers, for example).

Had the development team realized that some engines, particularly turbocharged engines, produced the levels of blowby that they do, I don't think AV-1 as formulated would have ever been on the market.

MolaKule · Oct 28, 2004

quote:

The reason both the Mobil and Amsoil products were pulled off the market was the cost of liability insurance in relationship to the small amount of oil sold, not because they were bad products.

I was told that the the oils were pulled from NA markets because of the tort situation and happy tort (litiguous) lawyers here, but it was still marketed in Europe.

quote:

This is a good example of where chemistry and the laboratory end and the field tests should begin. No matter how bright the formulater, if you don't understand completely what the conditions of use will be, both theoretical and practical, you're eventually going to experience a design failure.

I couldn't agree more.

This is where the internal Tribologist and chemists should have given the formulator/chemist complete specifications. Too many times, it is marketing specifications that drive formulation, and of course, marketing never to seems to get it right.

Bottom line is, formulator needs to have as much information on application as possible, and then run tests on as many different engines as possible.

And there are many times when many problems show up because of misapplication by user, or the user doesn't follow application instructions.

With today's new organic Detergent/dispersants, I don't see why a full synthetic aviation oil can't be formulated.

Jimbo · Oct 28, 2004

quote:

Originally posted by MolaKule:

I was told that the the oils were pulled from NA markets because of the tort situation and happy tort (litiguous) lawyers here, but it was still marketed in Europe.

With today's new organic Detergent/dispersants, I don't see why a full synthetic aviation oil can't be formulated. [/QB]

It was foolish to continue marketing in Europe since there was a real problem. Was Mobil too arrogant to admit failure, maybe. Is it still marketed there today? No.

Are organic disperants totally ashless? Can they scavenge large amounts of lead compounds from the ring area?

The Mobil AV-1 story

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