What is Marvel Mystery Oil?

When running older junk, as I used to, I relied on it a lot to smooth out the motors.
During the time ( during rationing and hard economic times ) of those constant oiler tanks
( shown above ) flatheads needed help with sticky valves, since the valves are not awash in oil like OHVs. As a kid when hanging in gas stations, Yes I hung out in many, I would see the small cans of valvetop oil in every brand.
An old mechanic ( wrenchin since 1920 ) told me a new car salesman ( in th'50s )
Tipped him off to the practice of each time he got hold of a demo, He'd get a quart and pour half into the engine, the rest in the tank. Then drive the hell out it,, or as we say today
Like Ya stole it.
During my time of same day delivery service I picked up an E250 with a 110 thousand miles.
Running near a tank of gas a day I found that the condition of deiseling when shut off was cleared up in Ten days of 4 ounces every tank.

 

My dad was big on it. We would soak rusty bike chains in it and after a few days they were freed up. I have fogged engines with it for storage for decades.

My brother (at a young age... ) drank some, the poison control number was by our wall phone. My dad then built a high shelf to store all the car liquids on.

 

I use in everything except my two daily drivers. Basically any engine that doesn’t get run regularly gets a dose.

 

Here's an MMO rating & review from a newer MMO thread

"Balanced & complex, this marvelous mysterious red is harmonious, even elegant, with a clear deep rich garnet color, a pleasant delicate bouquet and a curious lingering finish on the palate when siphoned. It pairs quite well with just about any gasoline and oil."

 

And it also cures, headaches,heartaches,stone aches,hemorrhoids , and hair on the face, it will cure what aisles you, if you don’t have anything??? It will give something !!!

 

There's a thread on here (sorry....I don't remember the name of it) about a guy that put MMO in his Model A and the fiber cam gear disintegrated. That leads me to think it has a pretty aggressive solvent (acetone maybe?)...