Marvel Mystery Oil

JBrown243

Pre-takeoff checklist
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Jason
Any one ever use the stuff? I have 15 gal Aux tanks that I want to keep empty (like <2gal) for more useful load, the tanks are bladder type and I'm concerned with them drying out. I've heard that I can put this stuff in the tanks and it will slosh around with the fuel while I fly and coat the tanks so they will not crack or dry up. I'm just concerned about adding this stuff to the fuel. Is it safe? Will it cause any problems when I later use the Aux tanks? If I do use it, How much should I use for each tank?
 
Any one ever use the stuff? I have 15 gal Aux tanks that I want to keep empty (like <2gal) for more useful load, the tanks are bladder type and I'm concerned with them drying out. I've heard that I can put this stuff in the tanks and it will slosh around with the fuel while I fly and coat the tanks so they will not crack or dry up. I'm just concerned about adding this stuff to the fuel. Is it safe? Will it cause any problems when I later use the Aux tanks? If I do use it, How much should I use for each tank?

Ran across a guy when doing an annual on my Mooney. He was finally replacing the engine in his Mooney 231 which had a reputation for never making it even close to TBO. He'd run 400 over TBO and it was still going strong when he decided it was time to overhaul.

This guy should have been a salesman for Marvel...he swore up and down he'd never fly a plane without it and that it was the secret to him running beyond TBO on all his engines. He used it as an oil additive and, I think, a fuel additive.

I have no idea if it was true...but he had me thinking!
 
I havent run the stuff (also not sure if it's FAA OKed, though I would doubt it), the guys running Franklins swear up and down by it, as do most running auto STCs.
 
I know a guy who owns and flies several vintage airplanes and swears by it as well. "He's" seen it first hand remedy stuck valve problems. 4 oz per 10 gallons of fuel... just sayin'

Mike-
 
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The recommended amounts are printed on the bottle. You're never going to find any scientific proof that it provides any benefit, only opinions and hear-say. I'll go out on a limb and say that, used as directed, it's not going to cause any problems. It's also great for cleaning tools and a billion other uses. Smells nice too.

It's not FAA approved and don't ever add fluid to your whiskey compass 'cause you're not allowed to do that either :rolleyes:
 
There is nothing in it that would be beneficial to the engine. It is approximately 75% mineral spirits, and 25% stoddard solvent, a little red dye and some "smellum". In a high performance engine, eg. turbo'd, it might increase the chance of detonation. I would contact one of the bladder mfg's and simply ask them about putting it in a bladder.
 
Hey' it's minty fresh. My grandmother always raved about "mystery oil" for years. It wasn't until I inherited her car and was down at the auto parts store getting stuff that I found out what she was talking about.

As pointed out, it's just some light solvents and a minty fresh scent.
 
MMO or Snake Oil is controversial to say the least.

Being a 170 owner, I have heard it recommended mostly for O-300's that are prone to sticky valves. As Silvaire mentions, there is really no scientific evidence that it works or doesn't. I have seen folks on the 170 board swear that MMO prevents stuck valves and they will throw out all kinds of personal observations to try and prove that. One the other hand there is an equal number of people who have used MMO regularly and still had stuck valves and swear that when they stopped using it, they never had another problem.

Then there are plenty of folks who have never touched the stuff who also have never experienced a stuck valve.

And as Silvaire said, it is not FAA approved. Aside from that, people using it for their perceived engine health do put the stuff in their tanks.

YMMV
 
I seem to recall Ed Kolin once stating that the solvents in MMO are actually damaging to bladders.
 
I know a guy who owns and flies several vintage airplanes and swears by it as well. "He's" seen it first hand remedy stuck valve problems. 4 oz per gallon of fuel... just sayin'

Mike-

That is 4 oz. per TEN gallons. I use it to lubricate the door slide on my Mooney and the hinges on my C150.
 
There is a good chance that you won't do any damage if you stick to the recommended levels.

But there is an NTSB report out there that blames MMO for bringing down a banner tow airplane due to excessive quantities.

I would also add that back in the olden days, I used to work at one of the larger auto companies. Down the hall from my desk was the fuels and lubricants department - the guys (and guyettes) who study this sort of thing for a living. One person had two collections on top of a couple file cabinets. One was labeled "good stuff" - pretty much brand name oils. The other was labeled "Schlock - Garbage" and had all the various aftermarket additives from the wishful thinking isle of the auto parts store. Guess which collection contained MMO...

But we all know that engineers are stupid and actual test results don't mean anything.
 
I know a guy who owns and flies several vintage airplanes and swears by it as well. "He's" seen it first hand remedy stuck valve problems. 4 oz per gallon of fuel... just sayin'

Mike-


I had an old boat with a flat head four cylinder. The valves would stick unless I ran marvel.

I'll elaborate a bit. The previous owner used it. The motor was a 1970's atomic 4. I quit using it when I got the boat. 6 months later, valves sticking. Every once in awhile on start up. Happened 3-4 times, until I began using MMO again. Never had another problem.
 
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If you want to mix a lubricant with your fuel then use something designed for that purpose, 2-stroke engine oil. But your fear about your bladders is unfounded. If you have 1 qt of fuel in the tank then the vapor content of fuel at the top is the same as iff the bladder was full. Think about where bladders fail, almost always at the quick drain attachment, which is a spot always covered with fuel full or empty.
 
Point 1: I've always believed that Shell, Phillips, and the rest have a vested financial interest in producing and selling the best possible oil for your aircraft engine. Just ask Mobil what happens when you screw that up (Google Mobil AV-1 if you don't remember that far back). Further, they do not have any vested financial interest (to my knowledge) in any engine overhaul shops or engine parts manufacturers. Therefore, I figure that if any of these additives were really useful, the big refiners would buy up the rights, put it in their own oil, and either charge more for the better oil or grab more market share at the same price once we aviators found out how much better it is. And I doubt that any of the additive inventors would find the serious offer of a major oil company for such a product too small to accept.

Point 2: I heard about a test run a while back on some car engines. An oil additive outfit was running ads showing how they added their magic stuff to engine oil, ran the engine a while, and then drained the oil and ran the engine for like 20 minutes before it seized. "See," they said, "after using our stuff your engine can run for 20 minutes after the oil is lost!" Some consumer advocate outfit duplicated the test, but this time with a control -- an identical engine with the same oil but without the additive. Guess what -- the control engine also ran for 20 minutes and failed the same way.

Point 3: If your engine is still in warranty, you should be aware that Lycoming says that the use of any oil additive (other than LW-16702, an anti-scuffing, anti-wear additive -- see Lycoming SB's 446 and 471, and SI 1409, which you can them faxed to you free by calling Lycoming at 1-800-258-3279 or 570-323-6181, for details on which engines this is allowed/not allowed/required in) is unnecessary and against their recommendations – which could void your warranty.

There is one exception to this general advice, and that’s CamGuard. CamGuard’s history lies in the development of Exxon Elite back in the 90’s. They wanted superior corrosion protection during periods of disuse, and put in a package of additives not included in previous oils like Phillips X/C 20W50 and Aeroshell 15W50. One of the folks who developed that package later left Exxon and continued work on an aftermarket additive product which would give other oils similar capability. This product is CamGuard. Tests by Aviation Consumer showed that Exxon Elite was measurably superior to the other oils in corrosion protection, but adding CamGuard to those other oils produced similar results to Elite. Adding CamGuard to Elite showed little improvement over Elite alone. My suggestion is that if your engine goes more than a week between flights, you either use Exxon Elite or add CamGuard to whatever else you’re using.

So before you go dumping anything other than aviation oil per the engine manufacturer’s recommendations into your oil system, consider all three points and some additional words noted below.

Also, if you read Savvy Aviator Mike Busch’s column “Slippery Stuff” in the February 2011 EAA Sport Aviation (http://www.sportaviationonline.org/sportaviation/201102#pg92), you’ll see he says much the same as I’ve said above – don’t bother with anything but CamGuard, but CamGuard does appear to help.

And from engine guru Howard Fenton...

“Several years ago I finished a two-year blind study on [an oil additive].

“Using all kinds of aircraft engines from radials to flats where I had an oil analysis history prior to the owner starting to use the product and continuing on for two years as the owner continued to use the product. We measured the wear metal results over the study period and summarized them by specific engine group. Not 100% scientific but this was an independent study that I personally funded. I had no bone to pick with anybody one way or the other and the people who owned the product at that time were helpful but made no demands. I called it like I saw it.

“The net result was that the product does not hurt the engine and in a few cases (from testimonials) it seemed to help with valve sticking problems in some small Continentals and a few Lycomings. Our Tiger seemed to have a lazy valve on cold start which seemed to go away when I added the product. But, I no longer use the product and the condition has not returned.

“Now a personal opinion, if you want to spend $25.00 just do a short interval oil change and I believe you will get as much if not more for your dollars. I am also very skeptical of any snake oil that advertises using the phrase: ‘Try our unique “Engine Overhaul In A Can” 100% risk free!’

“To quote a famous aircraft engine man,(me) ‘There Ain't No Mechanic In A Can.’

“It won't surprise me to soon see its companion automotive product advertised with reference to the "FAA-approved" aviation additive. Testimonials don't turn me on and I have found that sponsors often get favorable comments. In fact, I have never known of a sponsored race car driver bad mouthing his sponsors products via the media.”

Regards,
Howard Fenton
Engine Oil Analysis
TUL

And from former oil company chemist Larry Tatsch

“Having worked in the Technical Service Department of a major oil company for 20 years, I know that every oil additive on the market is tested under controlled conditions in comparison with a company's standard lube products. Every additive tested by my company proved to be no better (but in some cases, worse) than the standard oil. Consumer Reports has also done similar testing over the decades with similar results.

“Lube oils are complicated blends of several base oils selected for viscosity and other properties, and packages of additives that include extreme pressure (EP) additives, neutralizing additives, detergents, etc. Additive packages can include as many as 10 components. There are very few secrets in blending oils, and most newer oils depend on changes to the base oils, such as synthetics, or incremental improvements in additive packages. Oil companies typically "reverse engineer" their competitors' oils to determine their additive packages - its a very competitive business.

“So much for fact. Now let’s do a little reasoning:

“Do we really believe that an oil additive exists out there that is so different that all the major oil companies have somehow overlooked it? This additive must be fully compatible with every oil made and must have no adverse effects. When added to the best oil available, it must provide advantages so significant that they are obvious in test engines. And despite its amazing performance, ExxonMobil failed to use it in its newest aviation oil!

“Does this seem reasonable? Not to me, with my knowledge of oil blending. When we see the photos of test engines, we should ask exactly what the additive was tested against. Was it the poorest quality straight mineral oil, or Aeroshell 15W-50?? And we all should realize that from Wheaties to Marlboro to oil additives, celebrity endorsements mean nothing. And finally, FAA approval merely means that the additive does no harm - not that it actually improves an already high quality oil.

“After reading Tom's summary of MMO use in oil, I have to add my comments to Ron Levy's. Besides all his sensible discussion about the actual value of this stuff, adding one quart of MMO to 5 or 6 quarts of oil HAS THE POTENTIAL OF DOING REAL HARM TO YOUR ENGINE.

“The reason: MMO has a very much lower viscosity than aviation oil. It will dilute the oil and dramatically change the viscosity of that 40 weight or 15W50, or whatever, to a much lower, but unpredictable, viscosity. Its the same as pouring one quart of kerosene in your engine.

“Our engines were built with clearances to accommodate specified oil viscosities. When you suddenly lower that viscosity, you run the risk of scuffing bearings and cams, which can lead to engine failure. It may be OK in many engines under various conditions, but at some point, a combination of temp and low viscosity will cause damage.

“So, is it really worth it to experiment with your engine using a product that has NO objective proof of performance???”

And on top of all that, you're talking about putting it in the fuel system, not the oil system. All that will do is make the fuel burn dirtier.
 
So Ron, your dissertation above advocates camguard in engine oil to help fuel bladders ?
 
But there is an NTSB report out there that blames MMO for bringing down a banner tow airplane due to excessive quantities.
Was thinking the same thing. An NTSB query for Certified Airplanes with reciprocating engines, using the keyword "additive" yielded 14 hits.
 
(Google Mobil AV-1 if you don't remember that far back).

Seems that there's more to this story and it's not just the fault of the oil manufacturers.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=588577
Originally posted by StanW: said:
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.
 
My thoughts on MMO.

If you were a chemist working for a large oil producer, would you tell the world that MMO was better?

Basic ingredient is a "light distillate", or oil, by any other name is still an oil. it comes off the top of the cat-cracker at the refinery, and sold under several names, Mineral spirits, stoddard solvent, etc.

Any one remember the misfueling in So-Cal during the 90s ? less than 5% diesel fuel in 100LL and that got a lot of folks a new engine. (oil is oil remember?)

What happens to the BTU count when you add oil to a gallon of gas?
What will a higher BTU count do to the engine?

The smelly stuff is "Oil of winter Green" that's the major ingredient in liniment that makes you feel hot in the area that you put it on. It is also the major ingredient in penetrating oil that loosens rusty screws nut and bolts.

Red dye, ? ya gotta have something to make it look good?:)
 
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Wow, I didn't know there would be so much controversy for this matter. None the less, thanks for all the great responses. Took a while to read. I was already leaning away from using it in the first place but thought I'd get a second opinion. I just don't like adding something to the fuel that might cause problems. I still might pick up some for those other reasons posted above like putting on tools and using as a lube on various things around the house and whatnot. Thanks all for the replies.
 
If you were a chemist working for a large oil producer, would you tell the world that MMO was better?

Nope. I would just propose re-formulating the gasoline a little and take my bonus straight to the bank.

Basic ingredient is a "light distillate", or oil, by any other name is still an oil. it comes off the top of the cat-cracker at the refinery, and sold under several names, Mineral spirits, stoddard solvent, etc.

Stuff that is seperated from the gasoline at great expense.
 
Not a scientific conclusion but I had an old chainsaw that, after sitting in the shed for about it's 12th winter season half filled with old 2 cycle/auto gas mix, just plain refused to run right anymore. I dumped about an ounce of good ol' MMO in the tank and I swear, after about five minutes it cleared up and started running like a champ again. :dunno:

So, although I don't necessarily believe there is anything magical about the stuff it does come in a really cool looking bottle and it's a product I happen to like. There's always some on the shelf in my garage and in my shop.
 
I flew a guy's AA-5B awhile for him when he lost his medical, and he swore by it. Once, we had to fill up a couple hundred miles from base, and didn't have any in back. The whole way home he was nervous and just waiting for the engine to stop since we didn't add his special oil. He swore by it. I dunno if it does much good, but I'm pretty sure, in the right quantity, it won't do much harm.

About the bladders, I'd just call the manufacture and ask what they recommend for your situation.
 
...and finally we get back to the original question hahaha
 
My thoughts on MMO.

If you were a chemist working for a large oil producer, would you tell the world that MMO was better?

Basic ingredient is a "light distillate", or oil, by any other name is still an oil. it comes off the top of the cat-cracker at the refinery, and sold under several names, Mineral spirits, stoddard solvent, etc.

The smelly stuff is "Oil of winter Green" that's the major ingredient in liniment that makes you feel hot in the area that you put it on. It is also the major ingredient in penetrating oil that loosens rusty screws nut and bolts.

Which is why it kept the the valves from sticking in my old boat. My old boat: would not detonate from a slight reduction in octane, was designed to run on leaded fuel and did not get used frequently.
 
“The reason: MMO has a very much lower viscosity than aviation oil. It will dilute the oil and dramatically change the viscosity of that 40 weight or 15W50, or whatever, to a much lower, but unpredictable, viscosity. Its the same as pouring one quart of kerosene in your engine.

Which is what some guys used to do to their cars just before changing the oil. Add a quart of diesel, run it for a few minutes, and drain the oil. Left the engine sparkling inside.

If MMO is mostly petroleum distillate, it's no different that all those "top oils" you can buy to dump into your car's tank or engine to loosen stuck lifters and clean injectors. Look at the info on the cans in the parts shops. Almost all have the same stuff in them.

dan
 
MMO to run through an engine a couple quarts worth with a couple quarts of fresh oil low stress on the ground to get a rinse won't be a bad thing, just dump it again and refill with good oil.
 
MMO to run through an engine a couple quarts worth with a couple quarts of fresh oil low stress on the ground to get a rinse won't be a bad thing, just dump it again and refill with good oil.

flushing with a good solvent will do better job
 
Seems that there's more to this story and it's not just the fault of the oil manufacturers.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=588577

The problem with the AV1 oil was it's inability to hold the lead in suspension. Lead build up in the engine blocked oil galleries causing the engine to fail.
Shell oil is a blend of synthetic and petroleum base stock, therefore it is able to hold lead in suspension allowing the lead to be removed when the oil is drained
 
flushing with a good solvent will do better job

Yes and no; it is a good solvent, but one thing MMO let's you know when it is gone because the smell goes away. I always like to get them up to temp after a flush under low load conditions to boil out all the light end stuff remaining after draining. I've used Diesel fuel in the same capacity on big engines because I'll run it all through a centrifuge to get the fuel back out.
 
The problem with the AV1 oil was it's inability to hold the lead in suspension. Lead build up in the engine blocked oil galleries causing the engine to fail.
Shell oil is a blend of synthetic and petroleum base stock, therefore it is able to hold lead in suspension allowing the lead to be removed when the oil is drained

My research tells me that consumers were using the oil inconsistent with the recommendations, and that was my point.
 
There is nothing good about synthetic base stock in your aviation oil.
 
Actually mystery oil gives six hits. The previously referenced incident was probably this one:
http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20020916X01610&key=1

The others involve several people using unapproved autofuel (in one case ethanol) blends with MMO added and one was the case of Lycoming using MMO post mortem to clean up the engine to do some tests.

There was finally one where a guy made his own MMO out of lacquer thinner and hydraulic fluid and was going to go run up the engine to unstick the valves and some how inadvertantly got airborne. MMO only got a mention because they quoted the Sac Sky Ranch manual that advised against MMO to unstick an ALREADY STUCK valve.
 
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