I own a C195 & use MMO in the oil and gas (car gas)...There is a North American T28 on our fieldd & he uses it the same way...NOTE Radial engines.

One word


LIABILITY

Well things have to be FAA/PMA approved right?  But if they are also Mil Spec., then that is also approved, right?  If the military was using MMO in their aircraft years ago, then I would think that MMO has a Mil. Spec.  So legal to use or not legal. 

More curious to know what kind of success people have had that use it.  At 4 oz. per 10 gallons, I don't think anyone would ever know that you are using it, even if something went wrong. 

Putting MMO into the fuel lowers the octane rating of the fuel.  I have seen no DATA on it's use either supporting or not supporting it's use.  All of the information and recommendations are annedotal.  Anyone deciding to use it is doing so without any scientific support and should know that there are some potential downsides where minimum octane is concerned.

In the lower powered engines, using MMO is probably not harmful, but is of questionable value.  In the bigger, high compression engines, it's probably a bad idea.

Walter Atkinson
Advanced Pilot Seminars

Michael Meadows Wrote:
-------------------------------------------------------
>> What I would like to know is...what Marvel Mystery
> Oil actually IS.
> I'm thinking that part of the "Mystery" would be
> that if one is spending
> the money on the stuff, that person may be a
> little more inclined to be
> taking good care of the machine they are using it
> in, MMO aside...
> But then....maybe the mystery is magical and
> really does good stuff
> I think its extreamly unlikely that MMO would
> cause a problem.  At 4oz/10gal I doubt any oil
> would cause a problem.
> ...but then...whaddaeyeno?
> Michael


MMO is 30 weight base oil, varsol (charcoal lighter fluid), red dye and wintergreen fragrance.
It acts as a mild solvent which evaporates after an hour or so. For a few years it contained 1% dichlorobenzene which is a strong solvent but it attacks elastomer seals.

Ed

I agree about the reasons it is not FAA approved. It takes much $ to accomplish that. Also if someone in command in the FAA has some kind of vengence thing from the past broiling, then no matter how much dollars are spent it won't be approved. And it all may have nothing to do with how good or not the product is. Past examples, how come every Northrup flying wing was destroyed? How come top inventers such as Nicola Tesla was pretty much written out of the history books? So things like that do happen. Alot of outfits have been destroyed because they didn't agree to a merger or what ever. So the reasons may be more deep seated than any of us may know.

The product seems to do what is advertized, it took me many years to discoverit. I was one that thought it was snake oil too. But have since changed my mind on that. It  works great to keep fuel system corrosion down. And will preserve and keep rust down in cylinders. I think it is a way better protectant than say WD40, when burned it leaves a slight oily residue. Some day when better set up for it I would like to prove or disprove the claim for decreased octane using it, as I belive it is just to opposite. There is no Zn which is nice if you have silver in bearings since Zn will attack them.

Like some have mentioned, approved parts etc. Now just think of all the parts that have been approved by the FAA, and then at some point they fail. So just because the FAA approves something that does not mean it is something perfect. Just look at all the AD's. And that also means even the ever knowing manufacture does not know all they think they do either. No engine manufacture has yet to make an engine that has not failed in some fashion. So in simple minded terms the FAA approval doesn't really mean a thing. And in some cases Bob the home machinist can make a better part than Continental(or who ever) the engine manufacture. How can that be? Well if you don't understand manufacture and production you won't be able to figure it out. Because you have some preconsieved notion that a major manufacture makes top quality stuff. Not so.