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Marvel Mystery Oil

N395V

N395V

Well Known Member
This subject probably belongs in the "Neverending debate" section but there was no subforum for fuel/oil aditives.

The MMO debate came up recently on a Warbird forum and I was surprised to see the usual by the book crowd largely endorsing something that is not backed up by any objective evidence. Many put it in their fuel because Uncle Bob used it in WWII or they know someone who knows someone etc. There were no detractors on the forum.

Its purported use (for us) is as a valve lubricant to replace decreasing amounts of TEL and as a scavenger of that same lead to prevent plug fouling.

I have been searching for some form of proof to support or refute it's multiple miracle claims.

Finally I came acrosss a well conducted scientific evaluation by a diesel users group. Deisel users have become concerned with the loss of lubricity of diesel fuel as the epa has mandated lower levels of sulfur just as we fear the losss of lubricity providedby TEL.

While we do not use diesels this is a study of at least the lubrication part of the equation.

The study can be found at http://www.johnfjensen.com/Diesel_fuel_additive_test.pdf

It is interesting that it demonstrates not only no enhancement of lubrication but an actual deterioration in lubrication of the medium it is added to.
 
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After years of searching, below is all I have learned about MMO (other than the post above) which is scant little from an objective scientific viewpoint.

MMO is a lot like miracle drugs, a tiny kernel of fact wrapped in a thick layer of anecdotal attestations.

Most discussions on this subject contain a lot of claims with little fact and a lot of innuendo.To some extent what follows is little different but posted here for consideration and my justification for NOT using it. A lot of what follows is plagiarized from various anon: sources and it's accuracy cannot be verified.
Mystery History.
Marvel Mystery Oil was formulated shortly after World War I by
an automotive engineer named Burt Pierce, the man who invented
the Marvel carburetor, the standard automobile carburetor of its
time... GM bought up the rights to the carb and hired Pierce as a
consultant. The Marvel carbs were susceptible to clogging by lead and contam-
inants, (brown gook) so Pierce cooked up a mixture of light oil and various
chemicals to clean out the carbs... In 1923, Pierce went out on
his own and incorporated as Marvel Oil. He began selling his
'mystery oil'... claimed to be a universal lubricant and cleaner,
'one for all, and all for one.'"
Joe Howard (VP of Marvel Oil) is quoted "'The basic formula hasn't
changed since 1917.'
Aviation Consumer" had MMO analyzed, and it is a single-weight oil
with a viscosity rating of 4, peppermint odor, blue dye, and contains
phosphorus (presumably triphenyl phosphate, which is what's in Alcor
TCP and Lycoming LW-16702 additive). In oil, it acts as a solvent and
dilutes the base viscosity.
Nowhere could I find any scientific data or evidence that MMO scavenges anything.
According to the MSDS MMO consists of:
Naphthenic Hydrocarbons
Mineral Spirits
Chlorinated Hydrocarbons
Chlorinated Hydrocarbons are essentially Benzene.
As a gasoline (petrol) additive, benzene increases the octane rating and reduces knocking. Consequently, gasoline often contained several percent benzene before the 1950s, when tetraethyl lead replaced it as the most widely-used antiknock additive. With the global phaseout of leaded gasoline, benzene has made a comeback as a gasoline additive in some nations. In the United States, concern over its negative health effects and the possibility of benzene entering the groundwater have led to stringent regulation of gasoline's benzene content, with limits typically around 1%. European petrol specifications now contain the same 1% limit on benzene content. The United States Environmental Protection Agenc has new regulations that will lower the benzene content in gasoline to 0.62% in 2011.
Benzene was historically found as a significant component in many consumer products such as Liquid Wrench, several paint strippers,Prior to the 1920s, benzene was frequently used as an industrial solvent, especially for degreasing metal
One of the ultimate products of combustion of benzene is Hydrochloric acid HCL
CH4 + x/2 Cl2 → CH4-xClx + x HCL
Naphthenic Hydrocarbons are essentially Mineral spirits and similar to turpentine.
Mineral Spirits, also called Stoddard solvent, is a petroleum distillate commonly used as a paint thinner and mild solvent. Outside of the United States and Canada, it is referred to as white spirit. In industry, mineral spirits is used for cleaning and degreasing machine tools and parts. According to Wesco, a supplier of solvents and cleaning equipment, mineral spirits "are especially effective in removing oils, greases, carbon, and other material
The imputed reasons from the above to add MMO to your fuel are:
For MoGas users it dissolves the additives that cause buildup in the carb.
For big engine users it is possibly an effective Octane booster based on benzene content.
As a solvent it MAY help clean the valves and valve guides.
Reason to add it to your oil:
As a solvent it MAY help lubricate the valve guides.

Reason to add it to your oil:
As a solvent it MAY help lubricate the valve guides.
Reasons NOT to add it to anything.
One of the byproducts of combustion and heat degredation is HYDROCHLORIC ACID. Do you really want that **** soaking your MRB and turning it and your crank journal into a battery?
It dilutes and thins your oil making it less viscous. It also decreases an oils resistance to heat.
It cleans and removes oil and grease from metal. Probably not a great property when interposed between rings and cylinder wall, especially between engine uses.
I have yet to see any compelling data (other than attestations from happy users) that would suggest to me any concrete benefit from MMO.

Also look here http://www.ford-trucks.com/article/idx/18/141/article/Snake_Oil__Is_That_Additive_Really_A_Negative.html

I remain:confused:
 
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That's why they call it Mystery Oil

It's a mystery!
Now we need to know the full story on Mouse Milk!
 
Marvel Oil

I've been using for a few years now in my ECI IO 360. My process is as follows.

I add 6 oz to every oil change. I add 6 oz to each tank every other fill up.

My engine has 540 hours on it now. I burn less than a 1/2 qt in 25 hours. Oil temps are great, compression at annuals is excellent. I also have the oil analyzed every 50 hours by Blackstone Labs. There is no negative trend at this time. They know that I add it.

Do I have conclusive evidence that it works? No. But I don't have conclusive evidence that it doesn't!!!

One of our long time A&P AI's swears by it. It isn't causing any harm and makes me feel good. I guess I'll keep running it.
 
I have first hand experience...

...with MMO. The 1340 cu. in. Pratt and Whitneys occasionally had a valve stick and this happened to me several times on my radial powered Air Tractors and I'd suspend a can with safety wire behind the engine and had it sucked into the combustion chambers via the blower inlet. and the whole airport belched with smoke but it never failed to unstick a valve.

Earlier this year, my Honda mower hadn't been used in 5 years and the piston had stuck, so I squirted MMO into the spark plug hole and coated the piston and cylinder walls overnight. With a little bit of effort, I rotated the engine with the blade and finally got it started but it was blowing blue smoke, so I squirted MMO into the carb with it running and before long, it started running really clean....might have been a stuck ring, but I always have a can on hand and never add any to the oil.

Best,
 
I use MMO, and can definitely say that it doesn't hurt a thing to use it. I've soaked pistons with MMO and it will definitely loosen up carbon deposits. The J-3 I fly has chronic issues with lifters ticking and it definitely goes away after a half quart of MMO is poured in, for 20-30 hours where eventually it will return. Surely all of the above is anecdotal evidence, but I haven't seen anything which disproves any of my findings. Hence why its a mystery. :)
 
MMO/Many uses

I've a friend who can get a little queasy during steep turns and I wonder if a teaspoon or two of MMO would help him out before flight?

Seriously... back in the day we used to cure noisy lifters on GM products by dumping it in the carb at fast idle. Clouds of white smoke but usually worked.

But then again, ATF did the same thing.



.
 
N395V said:
Chlorinated Hydrocarbons are essentially Benzene...One of the ultimate products of combustion of benzene is Hydrochloric acid HCL
Click to expand...

Not sure where this info is coming from but it is factually incorrect. Not that Im putting any credence what so ever in MMO...

erich
 
Back in my pistol-shooting days, we always used MMO mixed with STP (the original thick stuff) on our .45s and other semi-autos. It cut jams and made the pistols much easier to clean than any gun oil. Now, I figure if you mix it with WD-40 and it will fix anything:)

Nope, don't use it in my O-320.

Bob Kelly
 
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Quote:
Originally Posted by N395V
Chlorinated Hydrocarbons are essentially Benzene...One of the ultimate products of combustion of benzene is Hydrochloric acid HCL

Not sure where this info is coming from but it is factually incorrect. Not that Im putting any credence what so ever in MMO...

erich
Click to expand...

While I also do not put a great degree of credence in MMO I am not necessarily a detractor. Just a guy in search of some facts which relative to MMO are in short supply. The only documentable facts I have ever seen relative to MMO are those in the Disesel group study referenced in my first post which seems to me to be a well conducted study.

As I mentioned in my post I do not attest to the accuracy of the multiple quotes I lifted from multiple sources. I did however attempt to ascertain if there was some basis in science for much of what I read.

Relative to the comments above re: benzene, chlorinatedhydrocarbons and HCL I believe the various proponents of this followed the logic of

MMOs MSDS lists mineral spirits as a component, and I believe, a common contaminent of mineral spirits is benzene. The MSDS also lists chlorinated hydrocarbons. If I remember my organic chemistry when you add heat to this mixture the by products include a halogenated benzene and hydrochloric acid.

The MSDS also lists napthenic hydrocarbons which, I believe, are commonly called hydrogenated benzenes. So at least the MSDS for MMO lists the contents for the availability of halogenation of benzene and production of Hydrochloric acid during the combustion process. Given the multitude of dissimilar metals in our engines even a tiny concentration of acid cannot be a good thing. Now this may be hogwash but as a non chemist it makes sense to me.
 
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Right or wrong, I've always considered MMO as a mild solvent. I use it in cases where I want to flush the crud out of a long dormant engine or after a rebuild. I got this idea after reading how the warbird guys would pick up aircraft from surplus after years of storage and on the initial ferry flights home the oil consumption was as high as the fuel consumption. A gallon of MMO would often unstick everything within an hour or so, and the engines would settle in to normal.

Not sure I would run a bunch of it on a "regular" basis, but as a periodic treatment just prior to an oil change it seems to work pretty well.
 
i use it.......

in the fuel and oil for years now. during my sailing days the atomic 4 gas engine was sticking valves a lot. pull the plug, get a small allen wrench, put it in the whole and tap the valve back down. well when using MMO in the fuel there was no problem with valves sticking. that is proof enough for me. MMO and fly alot for the plane, vitamins, exercise, and eat good for me. hope to be flying my rv when i am 80.
 
MMO ingredients

FWIW...the primary ingredients of MMO are Stoddard Solvent and a light hydraulic oil. Stoddard Solvent is an effective fuel system cleaner (Chevron Techron). The hydraulic oil is similar to ATF, without the ATF additives, and is effective at softening/breaking up carbon deposits. Also as a light lubricant on close tolerance parts.
Years ago I collected some run time data, long since lost, on a number of industrial engines we operated, running on VERY dirty fuel. Without MMO they wouldn't run for long due to carbon in the combustion chamber and sticking valves. With MMO injected into the fuel they would run 24/7, for many 1000's of hours, top end much cleaner at overhaul.
From my observations of these engines running 24/7, I think MMO is useful for maintaining a clean fuel system and top end. For an aircraft engine (or car), I wouldn't personally use it in the oil unless I was trying to clean it out and then change the oil/filter. Or intentionally lower the viscosity in sub-zero temps.
Just my .02, at best...
 
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It worked for me

Years ago I owned a 1948 108-3 Stinson. When the temp got down to 40F or below one of the intake valves would stick. This was determined by an A&P mechanic. If you could keep it running long enough for it to warm up a bit it would run fine. He instructed me to add a 1/2 quart of MMO to the crankcase and fly it for 3 hrs or so. I flew it for less than one hr. The next time I flew the problem was gone. Afterwards I added a little to the oil about an hour or so before each oil change, I never had another problem.
 
My Cherokee 140 had a sticky exhaust valve on the #4 cylinder when I bought it, resulting in low compression of just over 60. Added MMO to the fuel shortly afterward as well as the Peterson Mogas STC and the next compression check on the cylinder was 78. The previous owner stated that he never leaned the engine during operation...

After adding a pint or so to the oil, the oil pressure slowly (over the course of running that oil to the next change) climbed to the point I had to remove 2 of the 3 washers from the pressure regulator to keep it out of the yellow. Pressure is now at 60 during idle and around 75-80 at full throttle (confirmed with direct pressure gauge).

I think the solvent properties were a good thing for the engine, short term, but I have not run it since. Certainly worth having in the toolbox, so to speak, as a possible cure for a "gunked up" engine.
 
Spectro Inc Oil Analysis

Notes I took at EAA670 meeting at Hick's Field from speaker that is an expert on oil analysis... He recommended AvBlend or MMO from studying many engines and oil samples.

Speaker: Rex Havis of Spectro Inc, Crowley, Tx on Oil Analysis.
Use AvBlend every 3 or 4 oil changes to prevent carbon build up that occurs around 500 hrs on Continental engines. Marvel Mystery Oil Additive needs to be used more frequently than AvBlend because slower acting than AvBlend.
If no filter, change every 25 hrs. Gets trash out.
If have filter, then change every 50 hrs. If only fly 75 hrs, change 35 hrs.
If haven't flown plane in year, change oil before flying.
$18.50 per oil sample analysis.

Note: My notes may not be correct, but this is what I thought he said. Sounded like he really knows his stuff.
 
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I mean, if you fill the tank with MMO, the plane ain't gonna run, that's just common sense. Can't blame the MMO for that one.

I had what I thought was high oil consumption at about a quart every 4-6 hours. My oil also get filthy in just 10 hours.

Mike Busch/ Savvy recommended a ring wash, so I did it as directed, and 2 cylinders I simply could not get the wash to flush through.

On the advice of a friend, I put the recommended amount of MMO in both the fuel and oil, then flew for about 10 hours. When I drained the oil, it was really dirty, and the screen had lots of gunk in it, where previous changes it was always really clean.

When I attempted the ring wash again, all cylinders were freed up.

Was it the MMO? I'm not sure, but I'll continue to use it. The jury is still out on whether my consumption went down, plane has been apart since the last ring wash for annual and some other upgrades.

There are a boat load of videos on youtube of guys bringing compressions up with MMO. I think at the very least, it's a remedy for stuck rings.

As for it reducing viscosity as someone said, my Blackstone Oil analysis says otherwise. Viscosities from the MMO sample were right with my previous samples with no MMO.
 
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