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Mixing Marvel Mystery Oil with fuel

G

graywoodworking

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For those of you who use MMO in your fuel, how do you make sure the MMO is mixed thoroughly before flight?

The other day I decided to try MMO, so I dumped 8 ounces into a full, 25 gallon tank. A couple of days later I took a sample from that same tank and it was red in color. Evidently, the MMO settled to the bottom of the tank. I flew for an hour, using fuel from the other tank in which I did not add MMO. The flight seemed to have thoroughly mixed the MMO and fuel as a later fuel sample was nice and blue as expected.
 
graywoodworking said:
For those of you who use MMO in your fuel, how do you make sure the MMO is mixed thoroughly before flight?

The other day I decided to try MMO, so I dumped 8 ounces into a full, 25 gallon tank. A couple of days later I took a sample from that same tank and it was red in color. Evidently, the MMO settled to the bottom of the tank. I flew for an hour, using fuel from the other tank in which I did not add MMO. The flight seemed to have thoroughly mixed the MMO and fuel as a later fuel sample was nice and blue as expected.
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Never put it in fuel, always with an oil change. The 200hp lycoming had 1800 hirs and never stuck a valve.
 
Is it the marvel or the mystery that makes you think it’s a good idea to add it to fuel?

What the heck are you thinking?
 
From the Marvel Oil Company, if you use it: https://marvelmysteryoil.com/blogs/how-to-use/automobile

1710042284486.png
 
When I was a lad, pumping petrol after school, our big ‘upsell’ was upper cylinder lubricant. Looked very official in its little mini oil bottles.Little bottle for half a tank, big bottle for a full tank was the recommended dosage. I suspect it was sewing machine oil or similar. Some customers swore by it, others not so much. Can’t say the non users were queuing up for top end rebuilds. The boss even offered us an incentive scheme to try and push more of the stuff. When I quizzed him about what It actually did, the best answer I could get was ‘…it can’t hurt, can it?’
Just a tale from days gone by.
cheers, DaveH
 
MMO is light machine oil, stoddard solvent, red dye and a touch of wintergreen so it smells nice. It may not harm anything if you don't overdo it. But, I seriously doubt it'll improve anything as a fuel additive.

Instead of MMO, maybe try some Decalin. It'll help prevent lead buildup on your valves and plugs.
 
For what it's worth:

My totally unscientific experience over the last 9 years and nearly 1700 tach hours:

When I added MMO to fuel (at the ratio published on the label):
- I premixed the fuel with the MMO in 5 gal Home Depot Aviation Supply buckets, then poured it into the left fuel tank. 10 gallons, balanced against the similarly-filled right tank with no MMO.
- Next morning, that same left tank was leaking fuel from the fuel sump sample valve. The leaking fuel was pink. I do not know what seal O-ring material was used on that sump valve. I don't know if it was rubber, vinyl, silicon, unobtanium (I know...shame on me).
- My conclusion: MMO causes some sump valve O-rings to soften and allow a fuel leak.
- My corollary conclusion: MMO in fuel is not good in my RV.
- The unknown: I have no idea whether MMO was indeed actually useful or detrimental as a fuel additive for valve sticks, piston health, fuel economy, global warming, world economics...etc.

When I added MMO to my oil (at the ratio published on the MMO jug label):
- I have IN THE PAST added MMO to my 20-50 oil...and then experienced stuck valves (more than once, and always in the wintertime). Sal (the Cylinder Whisperer in north Texas) said: "You added an oil thinner (noun) in the summertime to thin (verb) oil that was already thin (adjective). It was then thinned (verb) even thinner (adverb) by the summer heat."
- Per Sal's strong recommendation: In the summertime I use Phillips 100AD oil and added MMO. He also suggested I pay attention to Mike Busch's red box advice.
- Per Sal's strong recommendation: In the wintertime I use Phillips 20-50 oil with NO added MMO. He also suggested I pay attention to Mike Busch's red box advice.

For three years now, I have had no further problems. Thus:
- My conclusion: MMO in engine oil is good in my RV, when combined with refinements to my CHT management (think Mike Bush) and engine oil type during hot/cold seasons.
- My conclusion: MMO in fuel tanks is not good for my RV.

So here's my battle plan:
- Winter: Philips 20-50, no MMO.
- Summer: Philips 100AD with MMO at each oil change, with MMO at the labeled ratio.

By the way, Blackstone loves my oil analysis numbers.
 
Guys,

This is one of my most hated OWT's, because snake oil is easily sold. MMO might be good at penetrating a seized connection (use kerosene), but as for its value in engine oil or fuel, that is zero. The only impact it has on fuel is degrading its octane number quite a bit. Do you really want to be doing that?

My good friend and APS partner George Brady of GAMI, who has taught me more about fuels than I can recall, has said this in the past. And if it had merit he would say so.
MMO is 30 weight basestock, 25% Stoddard solvent (varsol), 1% dichlorobenzene, red dye and wintergreen fragrance. The solvent evaporates within 15 minutes of starting the engine.

I have a few questions:

1) What is it supposed to do when added to the engine oil? It's 30 wt. oil with 25% varsol which evaporates in the first 15 minutes. Red dye? Wintergreen fragrance? That leaves the 1% dichlorobenzine... Just what is that 1% supposed to do?

2) What is it supposed to do when put in the fuel? That's the "mystery" part, I guess.
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StuBob said:
Is it the marvel or the mystery that makes you think it’s a good idea to add it to fuel?

What the heck are you thinking?
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I marvel at the mystery!! 😉
Remember - he asked "For those of you who use MMO in your fuel" Over the years I have had (on occasion) a stumble on take-off, used a tank of fuel mixed with MMO and the stumble has gone away. Just my experience - I know there are strong opinions both ways - I have never heard of or witnessed any damage if used properly.
 
Through scientific testing MMO was found to be a complete sham. It actually reduced the lubricity of diesel (one of the uses it’s been touted as a benefit for years, and where a lubricity improved is actually needed). It’s 150 year old snake oil I’m afraid. I will not allow it near anything I own. There are excellent oil and fuel additives these days that offer demonstrably improved results but this carnival scam fluid isn’t one of them. YMMV
 
Rv6mike said:
Never put it in fuel, always with an oil change. The 200hp lycoming had 1800 hirs and never stuck a valve.
...
Sorry it was 20 years ago.. If memory serves me right it was about 6 oz. It was a early Cardinal with a total of 44 gallons.
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44 Gallons of oil in a Cardinal?
 
Roadjunkie1 said:
🍿🍿🍿🍿🍿🍿🍿Buttered, please. With a little garlic salt and cheddar cheese sprinkles.......:LOL::ROFLMAO:
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I have never had it with garlic salt but I do like garlic so I would like to try that.

MMO has worked well for me as an air tool oil over the past three or four decades. I have never used it on my airplane but I know people who have. Some of them swear by it and some swear at it. I always have some MMO in my shop.
 
RV6_flyer said:
I have never had it with garlic salt but I do like garlic so I would like to try that.

MMO has worked well for me as an air tool oil over the past three or four decades. I have never used it on my airplane but I know people who have. Some of them swear by it and some swear at it. I always have some MMO in my shop.
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If you like garlic.......! Better than plain salt!

I have that same can of Marvel Tool Oil in my shop. I use it on my tools but it also works very well as a cutting oil. Helps on aluminum and steel! I have had the same can since 1992! Should last until my relatives inherit the shop!! :ROFLMAO:
 
Roadjunkie1 said:
If you like garlic.......! Better than plain salt!
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I need to keep my salt intake down so I have garlic Parmesan powder made just for popcorn.
Roadjunkie1 said:
I have that same can of Marvel Tool Oil in my shop. I use it on my tools but it also works very well as a cutting oil. Helps on aluminum and steel! I have had the same can since 1992! Should last until my relatives inherit the shop!! :ROFLMAO:
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I have several gallon cans of MMO that I inherited from the owner of the hangar next to me when he died 20 years ago. I never considered using it, never opened the cans, and never will use it.
If any one wants the MMO in my hangar please stop by and you can help me free up some shelf space for something I will use.
 
Looking at this from a fluid-property perspective, MMO is a relatively thin oil-type stuff but still slightly heavier than fuel. Gasoline/fuel, regardless of which type, is a pretty decent solvent. Unless you are putting MMO in a completely empty tank, there is going to be fuel in there. So: MMO is going to immediately be diluted (read: mixed) with the fuel. If you are filling your tank after putting MMO in, there is plenty of fluid 'turbulence' inside the tank to mix the two. I suppose if you S L O W L Y dribble it in the tank (and you would do that because.........?) it might , being slightly heavier, sink to the bottom and slide towards the quick drain. I have not used MMO in SuzieQ but have used it in the Cub for decades. I put 2 oz per 5 gallons (the recommended amount for gasoline) in the cans before heading over to the local Murphy's Aircraft Fuel Station (just North of Walmart... 😊) and it gets thoroughly mixed when filling the 5-gallon cans. I tried it once in the oil but found it dropped the viscosity of the oil enough it was more prone to heat up to near redline. I have not tried it in straight weight oil.

🍿
 
If there was this magikal ingredient that increased lubrication, removed sludge, and didn't have any negative impact why wouldn't the oil companies already include it in their products?
 
walkman said:
If there was this magikal ingredient that increased lubrication, removed sludge, and didn't have any negative impact why wouldn't the oil companies already include it in their products?
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Better question would be if there was why wouldn’t a more modern company than 200 yrs old figure out a way to sell it without the chew spit smell added. Well in fact they do. Fuel lubricants are all over the market and some perform better than others. However none of them are marketed toward carbureted engines because they don’t benefit at all from them. My modern diesel injection systems do, so I used optilube summer blend which was the leader in the tests I saw for cost per lubrication increase. As mentioned only one lube actually reduced lubricity and it was this mystery oil. Id suggest mixing ATF into the fuel before this garbage. But we digress, a lot.
 
YellerDaisy said:
I just pour it into the already filled wing tank. Never had an issue.
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Same as I do. Sticking valve issue went away when using MMO mixed with the Phillips 20w-50 cheap oil.

If you buy the Phillips Victory with Lycoming additive you don't need MMO. Completely switched to Aeroshell 15w-50 with the Lycoming additive. No longer use MMO.

BTW-Local aviation company that fly's a Techam back and forth to Anchorage tried the Phillips 20w-50 oil, fuel consumption went up over 3-gallons per hour, they switched back to Aeroshell.

Oil is the cheapest thing you can put into your engine, why risk with Phillips, plenty of writeups here about stuck valves. How many were using Aeroshell?

Use CamGuard on every oil change too.

Mike
 
mbauer said:
Same as I do. Sticking valve issue went away when using MMO mixed with the Phillips 20w-50 cheap oil.

If you buy the Phillips Victory with Lycoming additive you don't need MMO. Completely switched to Aeroshell 15w-50 with the Lycoming additive. No longer use MMO.

BTW-Local aviation company that fly's a Techam back and forth to Anchorage tried the Phillips 20w-50 oil, fuel consumption went up over 3-gallons per hour, they switched back to Aeroshell.

Oil is the cheapest thing you can put into your engine, why risk with Phillips, plenty of writeups here about stuck valves. How many were using Aeroshell?

Use CamGuard on every oil change too.

Mike
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I read today that a Boeing sub-contractor is using Dawn dish soap for a seal lube. Maybe if mixed with oil.....
-Marc
 
Personally I would not add it to FUEL.... for one of the reason not mixing and settling. However experienced A&P and AI's do use it in the oil.

Marvelous Mystery Oil is Petroleum distillates (hydrotreated heavy naphthenic), also known as mineral oil, 60–100% Petroleum distillates (Stoddard solvent), also known as white spirit, 10–30%.

It is like a solvent. I was reading a C182K model manual and they talk about putting FUEL in the oil for sub freezing starts... It is an optional fuel dilution system. MMO in fuel or oil does not surprise me...

STP has similar ingrediencies plus more goodies:

I personally am not an additive guy when it comes to airplanes. Although I put 6oz of XPD in my diesel cars tank. It adds lubricity low sulfur diesel lacks. It also helps cetane which is like octane rating to gasoline.

THEY DON'T CALL IT AMATEUR BUILT EXPERIMENTAL FOR NOTHING..
 
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