I am a firm believer in the stuff. When I put my things away for the year,after running stableized gas through it I remove the plugs and pour in an ounce or two and turn it over a couple of times to coat the rings and cylinder wall. It seems to work for me.

 

If it is a Mystery then I dont want to use it in my equipment. A good name brand oil should be fine, dont believe all the hype around about all this crap.

 

IMO its a waste of money. Most additives to gas and oil I am not a believer in. However once in a while I will use a small amount of sea foam in a tank of gas. Seems to smooth things out.

 

Mystery oil is snake oil to me. I will only use either Sta-bil or Seafoam.

 

As Henry said, MMO has been around forever. My dad used to sell drums of it to the airlines for use in their DC-3's, which had a propensity for sticky valves.

With the high quality oils we have today, it's not needed as an additive. However, it certainly is NOT snake oil. It worked very well many years ago with the oils available at the time.

I still use it as a penetrating oil, and for applications where a light oil is needed.

 

I run a mix of it in my Cummins through the fuel & it runs a little quieter. After I did that I put some in on occassion in my mowers & they run a little smoother as well.

 

I didn't even know they still made it. It worked good back in the old days.

 

That stuff is great, it's some mix of oil that has worked for A LOOOOONG time!
It works as good now as it did then! I run some in the fuel tank, oil, and down the cyl. of any engine that I want to store.

 

I have used it for years in my impacts and air wratchets. Keeps them from gumming up. Snap-on sells the same stuff as air tool oil.

 

Whether it fell from the sky or came up from the deep sea, no mysterious oils or magical foams for me, either.

 

I inherited a can of it when I bought the house I'm in now. In fact it's still sitting on the shelf where I found it.

Like Steve45 said above, back in the day when sludge was a problem the stuff was great. Unstick valves and rings, clean carbs out, remove sludge etc. Todays fuels and oils already have so many cleaners and additives in them that MMO just doesn't have much use and I'm sure their sales reflect that.

 

We use it at every oil change

 

used to be the only thing that would keep the valves on my 69 cadilac quiet