MMO “experiment” (1oz per gal of fuel)

[Ray S]

There is a youtube vid where a small engine repair guy tests MMO, Seaform etc with before-after checks on the heads and valves. They both work to clean carbon (as in the 1971 413), as they dissolve carbon and varnish.
Many "light oils" dissolve heavy crud - think lanolin or orange oil on your hands. The chemistry isn't my degree, but just slathering them on a carboned head for a day will soften and dissolve almost as well as sodium hydroxide.
What I did with the 50 yo Dodge was run it hot, pour some MMO in the carb and shut it off so it hot soaked. After about 6 cycles (while tuning the Holley and HEI) the intake bottom was clean iron, and the borescope showed clean valve stems and sparkling piston crowns.
Fresh oil change and it purred.
The (now retired) cab builder, Rick Walker had nothing good to say about most, crap, oxygenated gas - his advice was to run mid grade Chevron or Shell (the ones with additives) or add a qt of MMO per 60gal tank. He said never to use acetone in a carb engine.

TL-DR: those with modern, EFI vehicles should just stick with mid+ top tier gas.

 

[wings&wheels]

My HD mechanic said I almost my stock engine running 15 gallons of racing gas when the bike was a year old.

I replaced the carb, replaced that racing gas with normal pump gas but added Marvel Mystery oil on the advice of my Harley Mechanic,

What did your mechanic say was the problem with "race gas" that would damage a stock engine? Unless it was nitro or ethanol or leaded and you bike has cats, I can't see the problem except to your wallet.

 

[SOUNDMAN5000]

What did your mechanic say was the problem with "race gas" that would damage a stock engine? Unless it was nitro or ethanol or leaded and you bike has cats, I can't see the problem except to your wallet.

Good question as I could not figure out why race gas was a problem...

All I know this was about 1998 on my 1997 Evo, My local Sunoco added a Race Gas pump. It was blue gas and my memory fades but was 101 , 103 107 1 0 something, I cant remember exactly.

I ran one tank pure race gas no issue, then 2nd tank but on the 3rd tank the engine died but the carb parts, rubber, gaskets , seals and such ( after I removed the carb ) kinda had a melted dissolved look . I can't remember much discussion about my carb with my mechanic as I had been having issues tuning that carb , I had added a thunder jet and never liked it so this was a reason to go S&S Super E so I did! I could have rebuilt the carb and been fine but I always wanted a S&S so I replaced the stock carb.

My old Harley mechanic used the term "that gas is too clean" and he shows me, my exhaust that was always sooty ( is now still is to this day ) but after race gas was as clean as new exhaust!

I think he said I MAY have some vale seat or valve issues as he showed me that as well and was clean like a brand new engine! Once we got it started again I got lots of blue ( oil ) smoke.

He told be to ride it as it may be okay but to ride it with normal gas with MMO and see if the oil burning smoke stops, it did the blue smoke went aways in a day I guess.

But, during all this it was that stuck petcock It was fane, never a issue until racing gas! After the 1st tank I could feel that gas turn off getting tight, the I noticed getting tighter on the 2nd tank but on the 3rd it got so tight it stuck right in the middle of on and off! So I know for whatever reason that race gas was not playing nice with rubber parts , O-Rings etc that petcock. It was stuck! Could not move it!

My Mechanic didn't say much except you don't want to run that stuff straight in you bike, get it out and try Marvel Mystery Oil and see if the valve issue fixes itself!

I could actually and still can today "feel" the Marvel making that gas turn off slick as soon as I added a few oz to normal gas.

All this said, I still can't figure out why that blue gas caused a issue?

 

[Ray S]

Hmm https://www.sunocoracefuels.com/compare-fuels
the only blue is "Supreme" (leaded, no ethanol)
But it sound like some component is dissolving things, Supreme is mostly Naphtha and Toluene
https://www.ramosoil.com/company/customer-resources/safety-data-sheets-sds-msds/sunoco-racing-fuel/

 

[Jetronic]

Doesn't MMO contain phosphorous? If so I would not use it in an engine with catalytic converter.

 

[SOUNDMAN5000]

Hmm https://www.sunocoracefuels.com/compare-fuels
the only blue is "Supreme" (leaded, no ethanol)
But it sound like some component is dissolving things, Supreme is mostly Naphtha and Toluene
https://www.ramosoil.com/company/customer-resources/safety-data-sheets-sds-msds/sunoco-racing-fuel/

Keep in mind that was like 27 years ago so who know if the blue gas 27 years ago was the same as now? IDK?

 

[SOUNDMAN5000]

Doesn't MMO contain phosphorous? If so I would not use it in an engine with catalytic converter.

I understand some folks suggest using motor oil with Zinc could harm a CAT and in theory one may think Marvel and Cats may not play well together but lets face it, engines with cats do at times burn a bit of oil, heck I had a 50K mile Crown Vic that shot out blue smoke at every start up ( valve seats I guess ) and thats not going to hurt a cat or at least not before I ever would sell the car so I pose a question...

Has anyone EVER experienced a Catalytic Converter failure, or even a hint of a problem that was caused by Marvel Mystery Oil being in the gas? or in the oil? How about a Cat failure from any fuel additive or anything mixed with the gas or oil?

Marvel states its safe for CC's when used as directed so I question how much and for how long would one need to use to ever cause any harm?

 

[Jetronic]

I understand some folks suggest using motor oil with Zinc could harm a CAT and in theory one may think Marvel and Cats may not play well together but lets face it, engines with cats do at times burn a bit of oil, heck I had a 50K mile Crown Vic that shot out blue smoke at every start up ( valve seats I guess ) and thats not going to hurt a cat or at least not before I ever would sell the car so I pose a question...

Has anyone EVER experienced a Catalytic Converter failure, or even a hint of a problem that was caused by Marvel Mystery Oil being in the gas? or in the oil? How about a Cat failure from any fuel additive or anything mixed with the gas or oil?

Marvel states its safe for CC's when used as directed so I question how much and for how long would one need to use to ever cause any harm?

Any phosporous you burn is poisoning the cat, adding more isn't helping. How much MMO does one go through per 1k miles? depends heavily on the vehicle I guess.

 

[Ray S]

Any phosporous you burn is poisoning the cat, adding more isn't helping. How much MMO does one go through per 1k miles? depends heavily on the vehicle I guess.

Hmm, the MSDS has up to 1% Tricresyl phosphate, which is ~2% P,
If I use .5% MMO /gallon of gas ( a qt per tank), I get .5 * .01 * .02 = .0001 or 100ppm P, or, 900mg per tank.

This showed a small reduction of cat CO conversion after 200 hours with ZDDP/TCP engine oil.
This one says "An average of 14 percent (range of 11 to 18 percent) of the phosphorus estimated to passthrough the catalyst bed was found on the catalyst at the end of the test". The deterioration factor appears to be 2x the HC emissions, and 3 to 9g of P ended up on the cat "approximately 30% of phosphorus that is estimated to reach the converter is present on the catalyst after 80000 km."
The cat efficiency was 70% with P vs 80% with P-free oil/gas.https://sci-hub.ru/10.1108/00368790110408337

Methyl salicylate smells minty, and apparently is a lubricant

I don't care in the RV of course, but I did add O2 sensors, which can be similarly affected.

 

[ChrisD46]

MMO is to be used at a 320:1 ratio in the gas tank . For a typical 16 to 18 gallon gas tank that comes out to approx. 4 to 5 oz. per fill up.