Marvel Mystery Oil

C

Commander Toasty

Member
Just reading the other thread about gasoline grades, and I didn't want to hijack that thread, so started this one...

A lot of people commented to make sure to add the MMO to the gas. Boy - have I heard this forever in the airplane forums. Most of us piston engine fliers have heard countless stories about using MMO, and nobody knows what is in it etc...

Not true, and here is the basic thing to consider if you are considering using MMO in your gas or oil - it is a solvent - not a lubricant. Do you want a solvent in your engine between the piston rings and walls?

The reason MMO is so popular in piston airplanes is because they sit for a very long time with the same fuel in the tanks, and MMO keeps a fuel system clean (again - it's a solvent). This cleaning action is good for the entire fuel system, and particularly the carb, but not for the engine.

Yes indeed, many times your engine will run better if you run some MMO through it, but that is because you have an issue that needs addressing like sticky valves or gum buildup. But in a properly functioning engine you are just diluting your gas with a solvent.

I think the stuff is great, and I keep a couple gallons of it in the shop for soaking stuck tools, wiping down cables, freeing stuck engine parts and more, but not for lubricating.

When you just came across an engine long sitting and want to start it, do you soak the thing in oil overnight or MMO? Of course you soak it in MMO because it is a solvent and will get into the tight spots due to the low mineral oil viscosity mixed with naphtha. But once it is running you sure don't want that stuff in your bearings.

It does not completely burn in the combustion process, neither does gas, and some of it mixes with your engine oil. Consider the effect.

OK - I know a lot of the faithful out there will have huge arguments to the contrary, and everyone has to make their own decision, but I won't pour a solvent into a properly running engine.
 
Maybe we can sue them and make millions for false advertising as they claim now, as then that it is a lubricant;

"Marvel Mystery Oil® lubricates the entire fuel system-fuel pumps, fuel injectors or carburetors and the top-portion of the cylinders. These are areas, that by design, motor oil does not reach. Using Marvel Mystery Oil® in your fuel extends the life of these vital components by providing them with lubrication that fuel alone does not provide."
 
Goodness. If you google there will be more information than you can read in a week.

It is not disputed or in question that MMO is a solvent. The question is whether it should be in your engine. It has been recognized as a solvent since it was introduced in 1920.

Here is one to get you going, and you will recognize and respect many of the names you find having done the research.

http://www.rx7club.com/showthread.php?t=689158
 
Commander Toasty said:
. . .and here is the basic thing to consider if you are considering using MMO in your gas or oil - it is a solvent - not a lubricant.
Click to expand...
Apparently you didn't read the MSDS which reveals a napthenic base stock in MMO. That is a far superior lubricant than the n- and iso-paraffins that comprise standard motor oil. The halogenated solvent component facilitates penetration of the napthelenes into surfaces previously saturated with oil.
 
So if you pour Mobil 1 and acetone into your crankcase that's healthy because Mobil 1 is a lubricant?

You can't ignore the large 20% - 30% solvent content just because it also has lubricants in it. The stuff was formulated by a guy name Pierce as a carburetor cleaner, using very fine oils to soak solvent into tight spaces.
 
Well, I have used it as a TOP END lubricant in antique motorcycle engines as their designs allow for little top end lubrication from the bottom ends. Using a minimal amount per tankful is not going to wipe away all the oil film on the cylinder walls and I've found it sure helps the valves. All my motors are flatties except for two "F" heads (intake over exhaust).
 
MikeK said:
.......reveals a napthenic base stock in MMO. That is a far superior lubricant than the n- and iso-paraffins that comprise standard motor oil. The halogenated solvent component facilitates penetration of the napthelenes into surfaces previously saturated with oil.
Click to expand...

While napthenics make decent refrigeration oils, and are preferred in certain compressor applications, you'd be hard pressed to pass sequence tests for automotive crankcase oils with napthenic base, whereas paraffinics have a long history of success. Different products for different circumstances.
 
Naphthenic base oil lubricant

MikeK said:
Apparently you didn't read the MSDS which reveals a napthenic base stock in MMO. That is a far superior lubricant than the n- and iso-paraffins that comprise standard motor oil. The halogenated solvent component facilitates penetration of the napthelenes into surfaces previously saturated with oil.
Click to expand...

Not wanting to argue Uncle Bob and my area of expertise was not in lube oils at the refinery I was a chemical engineer at and I may be wrong but I am of the opinion that lube oils for automobiles and industrial uses are branched chain paraffins. The refinery I worked in long ago quit making naphthenic base stocks.

Not being aware that naphthenes are used in lubricating oils I did a little googling. Apparently there are some low quality lube oils made from naphthenic base stocks according to:

http://www.machinerylubrication.com/Read/472/base-oil-industry

"Naphthenic base oils were also available but not normally used in mainstream lubricants....they have a low VI relative to paraffinic oils so their lubricating performance and oxidation stability are relatively poor. They are normally used in specialty applications such as metal working fluids and transformer oils."

I'd be curious to know what specific lube oils use naphthenic base oils.
 
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Re: Naphthenic base oil lubricant

mrtexas said:
Not wanting to argue Uncle Bob ...........
Click to expand...


No argument with me Mr. Tex, your research underscores my comment about napthenics not being able to pass crankcase oil sequence testing. The two examples you gave and the two I had are very limited applications, and most of those have been supplanted by newer technologies.
 
The way I figure it "the large 20% - 30% solvent content" comes to 2.4 oz per 8 oz of MMO.
If we add 8 oz of MMO to 10 Gal (1280 oz) of fuel we get what 0.1857% "solvent".

"Do you want a solvent in your engine between the piston rings and walls?"

I can live with it!
 
Heh-heh-heh. We're talking about Model A's, right? Change the oil every 700-1000 miles? How much can get into the oil in tat amount of time? I've never had a problem (that I know of) with MMO. It has been especially helpful in gas at high altitudes and high temperatures. I don't know why. What is it? I don't need to know that. It just works. Kerosene might do the same thing. At least that was what my dad said he used back during WWII when he had problems with high temps and high altitudes.
 
I never leave home without it, I add 4oz to every single fill up and have seen a significant difference.
Go for it ...it works especially on older engines!
 
I don't really care what is in it. It is a good product, it has worked well for me and countless other people. What's the big deal?
 
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