Does Marvel mystery oil work as a fuel stabilizer?

katy

katy

Well-known member
Google says: YES,

How to Use It: Mixture ratio: Add 4 ounces of Marvel Mystery Oil for every 10 gallons of fuel.

Application: Pour it directly into your gas tank before storing the vehicle or equipment

So this year, not having any fuel stabilizer to use, and having MMO on the shelf, I asked google and then decided to use MMO instead of buying fuel stabilizer.

I looked at the price of fuel stabilizer and saw that MMO was actually cheaper than fuel stabilizer.

YMMV
 
Works for me !
 

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A couple of years ago my tractor stuck a valve open, after fixing that I started putting MMO in its gas and my Model A, no further problems.
 
Doggonit! I have been using MMO in my lawn equipment for years, chiefly because of the ethanol blended fuel around here.
Also Stabil in the tank for winter storage!
Could have saved some money if I would have known this!
 
Hello, that Marvel Mystery Oil been around a long time, remember red cans of it in my great grandfather’s garage,also had an oiling system that attached to intake manifold, consisting of steel lines and a glass jar.And it smelled good too !
 
I don't think it is a fuel stabilizer...I use it and Stabil...Stabil when parking for the winter....MMO always.....watch this if you have time:
https://www.youtube.com/watch?v=OHXYWxMkhog

If you have time watch this and save it...it compares all sorts of stuff we talk about...and this guy spent years looking at stuff... FYI
 
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AI Overview



Marvel Mystery Oil (MMO) acts as a lubricant and upper-cylinder cleaner, but it is not a true chemical fuel stabilizer designed to stop gasoline from degrading during long-term storage.
Why It Is Not a Dedicated Stabilizer



  • [*]No Chemical Oxidation Resistance: Modern gasoline oxidizes, loses volatility, and forms gum/varnish over a few months. MMO does not contain the chemical anti-oxidants found in dedicated stabilizers (like Sta-Bil or Seafoam) to halt this chemical breakdown.

    [*]Mixed Opinions: Many mechanics and forums note that while MMO is great for internal lubrication and cleaning, it should not be relied upon as a substitute for a dedicated fuel stabilizer if you are storing gas for more than a few months.



 
Why not go to the manufacturer and ask them ?! They say it can be used as a fuel stabilizer ! If they say it can be used as a stabilizer and it doesn’t would they still be in business ?! Or listen to someone on Tic-Toc , FB , or something in a black hole !
 
Actually, MMO does list it's "other uses" as a fuel stabilizer. The thing folks should know, is that MMO is mineral oil mixed with a smaller amount of basic solvent with trace amounts of some other additives designed to soften hard carbon. This is what makes it so useful in preventing valve & ring sticking. The caveat is that it really won't bind with moisture (water) in the fuel like ethanol will. Oils and solvents will mix but they count on movement of the fuel in the tank as in bumping around while driving. If it sets stagnant for long periods, all bets are off over time. Modern mogas fuel with ethanol is still going to deteriorate. Find a local station with No Ethanol fuel prior to setting it up for a long slumber.
 
Top cylinder lubricant. Can aid combustion by preventing "gel" of fuel additives.

Many feel a small quantity of ethyl alcohol will serve the same purpose minus the lubricant part. Today's ethanol gasoline serves the same stabilizing purpose.

Joe K
 
Buddy of mine swears by putting avgas (tinted blue) in his motorcycles when he puts them to bed for the winter, and his yard equipment. Says they fire up in the spring like he just put new gas in them. I've never tried it, to expensive.
 
Been using it consistently for well over 25 years, long enough that it came in the metal cans. I use it as a fuel additive only. I use it in everything from my lawn mower to my classics. Fuel lasts far longer and Seems to offset or at least prolong the effect of ethanol fuel.
 
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My Great granddad bought it for his then new fleet of AA's in the early 30s. Then used it in his WWII surplus semi tractors and 6X6's. He bought it in the 1 gallon metal cans. He ran it in the crankcase and fuel tank. Dad used it as a Top Cylinder Lubricant... aka in his fuel tanks.
IN 1986 Dad found a 1937 John Deere model A tractor in a field. It had rusted the air breather and exhaust in 2 from exposure. Locked up solid.
It broke free after several months of cylinders filed with MMO. We farmed with it for 10 years, never tore down the engine, no rings, nothing. The tractor still runs,, bought by our neighbors.
Yes, I use MMO in my fuel tank.
 
Hello,

I, too, have been using MMO continuously for 18 years. In my Ford via the nice "inverse oiler," and otherwise by adding 40 ccm³ to every tank of fuel.
Unfortunately, it is no longer permitted to be sold in Europe. Consequently, due to the nature of my profession, I have created a similar blend myself. I use it now for the past six months.

The Valves and pistoncrowns and head's chambers, there is only very low ash.
 

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used to use a lot of it but stopped when it got to 9 bucks a quart, now i use a little old style atf has to be a good cleaner to keep auto trans super clean and it's also a lube.
 
I put 3 ounces in at every fill up! Also did this for years with my '50 Buick. Works like a charm! Got the advice from on old Buick mechanic
 
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