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

Anyone have a before or after results of MMO actually cleaning in lawn equipment?!
I'm not a fan of the Farm guy on Youtube, but he did indeed show MMO cleaning carbon out of a run down lawnmower...

MMO isn't something most modern cars using proper fuel and FI cleaners really need, but at the same time it isn't "snake oil" and does benefit some (mainly older) cars as a mild FI cleaner. Not a fan of using it in oil sumps or as an "upper cylinder" lubricant for fuel systems though...
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This thread is just confirmation bias and bad ideas.

Don't put it in your fuel, and certainly don't put it in your crankcase to "thin the oil". Just use thinner oil.

MMO is snake oil, like at least half of the products on the store shelves next to it. It does nothing very well, and all of the things it "does" are done better by other products.
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Em, no, you can't write it off as "snake oil;". It does indeed remove carbon and sludge. Use it in a newer gas tank? NOOOO! Use it in a sump of anything? NOPE! More effective modern FI additives, yes. But it does indeed have cleaning properties and it's pretty cheap. Obsolete? Yes, perhaps. "Snake oil", no...
I wonder how many here say SANKE OIL but never have tried any additives before?
maybe the additive is not a permeant FIX but maybe if used before something breaks or worn out it could delay it from happening ?
who knows but if it help the owner feel better when using the additive so let them without calling them crazy....
BITOG Analysis:
a) What you like is snake oil, what I like is fantastic stuff!
b) Moly additives are snake oil. Moly in oil is fantastic stuff!
c) All engine cleaners are snake oil. Auto RX is fantastic stuff!

I have my own experience with MMO and this is what has been working for me. My thought is if you drive any vehicle the way they were intended to be used, you don't need to add anything to the gas or oil. Running fresh gas thru your engine will keep everything as clean as it can be. When I fill my 5 gallon gas can for use in my mowers, snowblower, and weed wacker's. I put a dose of carb / fuel injector cleaner in the can with a shot of MMO, then get gas. It gets as mixed up as good as it can get at that point. I never have running problems, or hard start problems by doing that. Every time something gets refueled, it gets a dose of treated gas. MMO was originally developed for marine engine that sit for months and the theory is that it provides a protecting coating in the fuel system. If that really is the case, I can't tell. But I can't say it has caused ME any issues. Like WD40 was developed to dry ignition wires in the marine world. But people use it for everything. I did witness once at the Marina I kept my boat in, the guy behind me has a noticeable lifter tick in his 4 cyl chevy engine. I saw him pour a can of MMO in the oil, then he left for about a hour or so. After letting it run for that hour, the tick had stopped. I listened for that tick every time I saw him go out, or come back in, it was still gone for the rest of the season. I'm not saying it will get your engine rebuild clean, just that if you have a small annoying problem and don't want to do a rebuild or repair, it might help you out. It's alot cheaper then a teardown.,,
Why did you use so much? Was this a special cleaning/ seasonal event?

4oz per 10 gallons is the recommended dosage. I use five for 13 gallon tanks on the ION and Calais. Pre-portioned in bottles I have collected. Yeah. I am that particular.... okay.... sick.

I've been using it on all three of my cars for years. The oldest, a '63 Slant Six has an Ampco MMO oiling device to produce a steady delivery. MMO even sold it's own oilers at one point.

I may get one for the 2.5 liter in the Olds.

It's not hurting anything.
Acetone does a much better job of freeing up a stuck engine and does so within hours, not days or weeks. It also will eat rust where as MMO is prone to causing rust. Also unlike MMO, acetone will readily vaporize and combust to aid that initial startup.

In terms of engine oil and fuel, it's definitely a snake oil. It's 70% pale oil with small amounts of isopropyl alcohol, light naphtha, and a pinch of TCP and chlorinated paraffin.

In the oil, the isopropyl and naphtha have low boiling points (179°F and 194°F respectively) and thus evaporate the first time the oil gets hot. The light oil left behind just lower's the oil's viscosity until it eventually evaporates as well. The chlorinated paraffins are notorious for causing rust/corrosion problems, and TCP is an EP for cutting fluids that serves no purpose in an engine.

In the fuel, the isopropyl lowers the stoich value and is a weaker solvent than the 10% ethanol already in the fuel. The light naphtha lowers the octane of the fuel. Both increase the fuel's speed index making the fuel less responsive and more prone to hard starts. The pale oil, TCP, and CP serve no purpose except to make the emissions equipment wonder why you hate it so much.
I'd be afraid to put acetone in anything, even if it hung around long enough to do any cleaning. No?
82 S10 2.8 5 peed MMO netted me 1 to 2 mpg consistently M1 oil
02 BMW R1150RS MMO netted me consistent 2 mpg M1 oil
Only these 2 vehicles ever benefited from mmo. I do not know why I do not think it was some funny interaction with the M1 All my stuff runs M1 or WM syn, I have tried MMO in all of them
Side note, they do consume less M1 VS WM Full Syn oil, none are in excess of 1 quart per 7500 mile change, some are none, others are 1/2 to 1 quart

A shot of MMO in my 2.4 gal. tank for lawn mower with a little Stabil seems to provide a benefit ; the vehicles get TCW-3 oil at a lighter 960:1 ratio .
I use it in an attempt to prevent fuel tank rust on infrequently driven cars, not for any performance benefits and never in oil. Back in the dark ages when I had my fist Tr6, the local old Brit specialist recommended MMO in the fuel to leave a light film over the ullage arear of the fuel tanks. The Triumphs had a propensity to rust through at the 'water line', and this was his solution. Seemed to make sense, and I consider it cheap insurance.

The TCP does scavenge lead, and the rag wing (and Ercoupe) crowd where I learned to fly used MMO religiously on their old stuff. Never heard of any problems, but I never used it in an aircraft.
Earlier this year prior to my oil change, I ran some water (0.5L) through my engine via a vac hose and keeping the revs up a bit, then did the same with MMO. Bit of blue smoke out the exhaust, EML came on. Then went for an Italian tune up. Also added a bottle to the oil too.

I've owned the car 11 years and done this same procedure but with water+carb cleaner or water+Seafoam a few times, EML never came on with them though. Reset the EML the next day, no problems.

It's running strong considering it's got 170,000 miles on it, and achieved a record 41 mpg this year (and three lots of 40 mpg) which is bloody amazing for a redblock turbo.:giggle:

Is this due to MMO? :unsure: Probably not.😅

Reading some of the comments on here makes me not want to put it in my engine anymore though.😯
Been using it for years! I stick to 3 or 4 oz per 10 gallons I'll leave the experimenting to you 😁

Truly though I can tell a difference in the smoothness of the idle especially in my vehicles with or without. And we have proof that it does clean carbon so there's that...
I can give you a real world positive experience with MMO.I used to own a Nissan 370Z. A known issue was wonky fuel gauges, they wouldn't register as full even when owners knew the tank was topped off. A dose of MMO (the recommended ratio, not an excess dose) would free up the float or whatever it was that was causing the gauge to read improperly and then the next few times I filled up the gauge worked properly. A few months later, the problem reappeared and another dose of MMO would fix it.

So it does have some useful solvent properties and the negligible cost of a bottle of MMO to be used every 3 or 4 thousand miles as preventive maintenance is not enough to make me worry about how much lighter my wallet was. I now use it in my Mazda CX 5 every few thousand miles as well. Just because.
2 stroke oil works just as well.
I was thinking about this as I typed it up in the “exhaust pipe” post 😝

But I did something pretty reckless and out of character for me

I put in 18 ounces of marvel mystery oil in the Kia’s gas tank then filled it up with my normal e-0 91 followed by multiple 2nd / 3rd gear wot pulls and normal driving for days…

My results are this:

-There is not a speck of carbon on the exhaust…
- noticed no “ negative” difference in drivability.
- Can’t say I even noticed a “positive” difference

Last minute thoughts:
- The 2.4l engine is already “clean” (I have been using marvel mystery oil and ethanol free fuel in this 2.4l for many thousands of miles but at the recommended dosage) so the marvel mystery oil has nothing to “clean” and I am just benefiting from the “lubrication” properties of the MMO

-The marvel mystery oil even at double the dosages is a waste of money, and it has no beneficial properties for “cleaning” Especially on a daily driven car that already uses good quality fluids

Talk to me: am I wasting money for mmo in fuel? I remember picking up my first bottle at 16 and I have been using it since… but I have to be realistic with myself.

I am willing to put the bottle down… it will be hard but I have spent thousands of dollars on this product over my life and now I’m starting to feel like I bought into “snake oil” 😂 because I don’t actually know if it’s been “helping” all these years or not.

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Doesn't make you an idiot or a bad person. You feel like you should be eating crow , but I can guarantee everyone except maybe @MolaKule has done it. Getting that vehicle up to temp with some high rpm, quality fuel ⛽, and an occasional fuel additive with pea will give you the best chance.
first post here, mmo does what it says it does. i used about 6 oz in my oil for a whole oil change (3000 miles t6 15-40) and that was the blackest oil I've got from that car. it also stopped my lifter tick by gumming up some of the lifters, which hung one of my intake valves barely open and caused a slight misfire. when I pulled the valve covers the engine was really clean, and most of the lifters worked normally. new lifters and in 200 miles my oil is still as clean as when I put it in.

MMO does clean and loosen gunk, but that loose gunk might be bad for your engine. i doubt a small amount of solvent in your oil will damage the engine, but at the same time I only run a few ounces when I do run it. i cant say what it does for injectors.

the old lifters were toast when I took them out, the little ring that holds the lifters together had disintegrated on most of mine, which isn't unusual for a Mitsubishi v6 with 200k miles on it
Marvel oiler.... the original upper cylinder lube

I wonder if they still use that "wintergreen oil" super solvent esterish lube too. Smells good so it has to work

Solvents and oils have their places, as do secret recipes whispered into ears formulas... especially if they are a sponsor of whatever.

Gasoline is a pretty good solvent too. How's the fuel dilution working out for the automaker?

When something works for you, then you should adjust whatever you've done for maintenance to avoid the problem. Obviously, this can't be done with a used car purchase because you get what you paid for. But even then, some balk at simple maintenance.

If you're looking for a solution to using cheap oil, never topping off the oil, missing oil changes, and creating new and interesting engines sounds, you're in the right subforum.