Marvel Mystery Oil - results were lacking

[PJPR01]

PJPRO1 - I don't think it was as high as a quart to 20 gallons. I had MMO injectors on two vehicles way back when (mid 1950's). This was an adapter plate at the base of the carburetor with a line back to a bottle (1 quart) of MMO. Had to refill the bottle about every 4 tanks of gas.

Good call...I read the bottle last night...4 fluid ounces for every 10 gallons of fuel is the recommended ratio on the bottle of MMO. 

I'll give it a shot on the various vehicles and moto and see what it does, sounds like it will do a better job than the typical fuel injector cleaners probably.

Interesting discussion...thanks all for the inputs.

[Triple Jim]

Sounds like a good mixture of arcane stuff.   No wonder things seem to work better and last longer with it ..... 

Lannis

If you like that sort of thing, put a cow magnet on your fuel line for more power and better mileage.

[Wayne Orwig]

MMO is about like Seafoam. It might make you feel good, but it is really nearly worthless.

[Lannis]

If you like that sort of thing, put a cow magnet on your fuel line for more power and better mileage.

The magnets for "atomizing" fuel ... the metal pellets you drop in your fuel tank ... the "200 MPG" carburetors .... the "Motor Mender" pellets and solutions for fixing your compression problems ... oatmeal in the radiator to stop leaks, and in the differential to quiet it down .... the JC Whitney "Uconvert'm" 2 barrel to 4 barrel .... No, no, DON'T tell me those are in the same class as Marvel Mystery Oil, I couldn't stand it!   I just know my bikes run better with MMO!

Lannis

[Triple Jim]

I feel you've left out the mighty J.C. Whitney Fire Injectors.

Wayne mentioned Seafoam, a mixure of oil, naptha, and isopropyl alcohol.  And to think we complain about alcohol in our gasoline!

http://www.onboces.org/safety/msds/S/Sea%20Foam%20Sales%20Company%20Sea%20Foam%20Motor%20treatment%20SF-16,%20SF-128,%20SF-55,%20Sea%20Foarm%20Trans%20Tune%20TT-16,%20TT-55%20February%202009.pdf

[Lannis]

OK, W and J,  you don't like MMO or SeaFoam ...  I can live with that.  (Aren't you relieved?    )

... but seriously now, Marine Sta-Bil is real stuff, isn't it?   I know guys who use it in salt-water boats and they say it stops tank rust and carb blockage right NOW, under WAY worse environmental and occasional-use conditions that our bikes see ....

Lannis

[Triple Jim]

Hey just having a laugh, if you don't like the stuff then...no disrespect intended.

No disrespect taken.  :)  I don't like or dislike any of the snake oil products.  I just choose to spend my money elsewhere.

... but seriously now, Marine Sta-Bil is real stuff, isn't it?   I know guys who use it in salt-water boats and they say it stops tank rust and carb blockage right NOW, under WAY worse environmental and occasional-use conditions that our bikes see ....

I assume the marine version of Sta-Bil works.  I just bought six quarts of STA-BIL 22275-CS, which is (one of) the one(s) they make for the current gasahol we buy at the pumps.  I have too many things with engines that sit around waiting for my attention most of the time.  I don't have any trouble with the fuel systems of vehicles I drive regularly, but I sure have it with the ones I don't.

[LowRyter]

I've heard of mixing some ATF with oil as a cleaning agent. 

[tcunnien]

Been teaching Small Engines at the High School level since 1981. Been to several Briggs and Stratton, and when they were making engines Tecumseh factory schools. Not claiming to be an expert by any stretch but have had quite a few engines apart over the years. I think you might be surprised at how clean the engine will be. The addition of detergent to oils made a huge difference for combating sludge buildup in small air cooled engines. No small engine manufacture has recommended non-detergent oils since the 1960s. Since the engine is on a snowblower it also is running in one of the cleanest environments for small engines. Very little abrasive dust is in the air during the winter. My concern would be combustion deposits built up on the cylinder head and around the exhaust valve. No amount of MMO in the oil will help that. Just like a two stroke a common tune up on a L-head engine back in the day was to replace the points and air cleaner and remove the head and decarbonize it. Of course the snowblower engines didn't have air cleaners. Tecumseh's were always fun cause you had to use a dail indicator to set the timing and points. Just my cent and a half.

[PJPR01]

Happy to report that after adding 2 fluid ounces of MMO to the Norge and taking it for a short spin, it's running noticeably smoother...probably also has another 15-20 horsepower at least...measured by the butt dyno.

The 911 got a 4 fluid ounce injection, and is purring like a cat...

Next test!!  :)

[Chuck in Indiana]

MMO is a good upper cylinder lubricant. Antique airplane engines do much more sitting than running, and tend to have stuck rings, valves, etc. because of it. A little MMO in the fuel and oil generally frees them up. <shrug>
When I am building an engine, I put some on the valve stems at assembly. A little dab frees up the ram on my reloading press, etc. 
Don't go knocking MMO..

[Triple Jim]

I've never priced it.  How does the cost compare to a quart of low end motor oil with half a cup of mineral spirits mixed in?

[Chuck in Indiana]

^^^^^ That would smell bad..

[Triple Jim]

Lowe's has low-odor mineral spirits.  That shouldn't smell bad.  That's what their own MSDS says is in it.

[Tom H]

I have used MMO to try to free up what I felt was stuck rings, low compression and smoking a little on one side. Squirted a little in through the spark plug hole, put my finger over the hole and a very short crank over to maybe swish it around with out blowing it out. Did the same on the other side. I would then let it sit for a day or two with the spark plugs in.

Did it do any good, I think so. Checked the compression after about a 40 mile ride. It did not make the compression like new, but it did come up considerably. And the smoking was all but gone. Rode it for about 100 miles and the smoking was gone. This was not the first time I've tried it on a engine that has been sitting and has seemed to help.

YMMV,
Tom

[Yeahoo Whoyah]

I've really enjoyed all the comments on MMO, very informative.  I didn't know the stuff was still made. Up until now my full can of MMO was on the garage shelf as a display item from last century. 

[sign216]

I've always wanted to believe in MMO, but when I gave it a good chance to shine...they didn't come through.

I mean, if you can't pull debris out of a 25 yr old side valve....


And I don't want to hear "how clean engines are now."  You don't think there's crud laying in the bottom of the crankcase?

[oldbike54]

 Think about this for just a minute Sign , this engine has probably never seen leaded gasoline , and modern oils are much better . Yes , it may be 25 years old , but how many hours has it been ran ? What makes you think it is full of sludge ?

 Dusty

[Chuck in Indiana]

I've always wanted to believe in MMO, but when I gave it a good chance to shine...they didn't come through.

I mean, if you can't pull debris out of a 25 yr old side valve....


And I don't want to hear "how clean engines are now." You don't think there's crud laying in the bottom of the crankcase?

Just FWIW. I talked to an *old* aviation mechanic at Oshkosh for quite a while a few years ago. He was working for the airlines back in the day. He said, naturally, they did testing with detergent and non detergent oils in the big radials.
Know what they found? The engines (without oil filters) ran a *lot* longer with non detergent oil. The crud just laid in oil galleries, sumps, etc. Detergents loosened them up, and the crud *went through* the bearings, etc. and continued to go through them.
Once they went to oil filtered engines, it was a different story.
So.
I, personally, wouldn't even try to get that old engine clean.

[sign216]

I, personally, wouldn't even try to get that old engine clean.

Ya know, that's actually the collective wisdom.  They say "leave an old engine alone."

But some of us just need to fiddle...

[Penderic]

Mmmm, I wonder how well it goes with shish kabobs?



 

[Sasquatch Jim]

  I will impart a minty aroma, not so sure about the taste though.

[Triple Jim]

Oh my God, that's a heavy lid!

[sign216]

Just to let people know; I started the threat because Marvel Mystery Oil (MMO) didn't drag much dirt out of my 20+ yrs old side-valve Tecumseh snow blower.  When I changed the oil, MMO didn't cause much dirt to come out.  So perhaps it didn't work as a pre-change oil cleanser?

Well, I opened up the head this fall to prep for the winter, and g-d damn, the combustion chamber is one of the cleanest I've seen.  Sidevalves are supposed to be inefficient and dirty, but this old Tecumseh is a gem.  Maybe there wasn't much dirt for MMO to take out to begin with.

Sorry to malign the famous MMO.

These photos are after I cleaned the head, but still show how nice it was for 20+ years of service.

[Roebling3]

Using MMO as a muscle relaxer and moisturizer was recommended to me. She said; 'The smell is even medicinal'. I didn't swallow any of that.  R3~

[old head]

I use it to keep the fuel injectors clean and reduce carbon build up.  does it work, who knows?  its not expensive.  I run it in my carburetors more often, I assume fuel injection is cleaner and leaves less carbon.

with modern detergent oils and regular oil changes, an engine shouldn't really get very dirty, IMO>

I recently bought a Jeep at auction, that wasn't running, straight 6, 4.0.  Plugs were really bad carbon build up, changed them up and ran water through the intake to clean out the carbon.  small amounts of water in hot engine, slowly introduced will break up the carbon and it will blow black smoke.  doesn't take much 6-8 oz is usually enough first time.  20k miles later, the plugs looked fine and it runs really good.

If its really bad, I might go back again after an oil change or two.

I use seafoam to fog my outboards if I am not going to be running them for awhile, Seafoam is expensive compared to MMO.  lots of youtube videos, sometimes it works sometimes not.

Old Head

[LowRyter]

I added a quart to my son's '04 Accord.  The thing still runs like a top but at 175k  miles it suddenly started using oil.  Someone  suggested that MMO might un-stick the rings.   I figured there was nothing to lose.

[kingoffleece]

I don't see how any valid  conclusion can be drawn from a sample of one that was done using a set of criteria and test procedure that may or may not be relevant.

[twowings]

I can't explain how the wind works, either...yet the leaves and flowers are moving just the same...

[Trialsman]

I only ever used it once and it really wasn't me.  A friend had an RX7 Mazda with a race crate engine he wanted to sell me.  He was in NC and it hadn't been turned over for 14yrs.  Rotarys are notorious for carbon deposits behind the apex seals which usually sticks them after long dormant periods.  Since this was a race motor with only about 1,800 mi on it, I wanted to make sure the apex seals were free.  I instructed him to pour MMO in every hole, spark plugs and down the carb.  I said do NOT turn it over but let it sit and I would be down in a week to pull the engine.  When I did it turned over effortlessly and the engine still runs today, some 10yrs later.  I never put anymore MMO in it but I start it at least once a month and let it run for a half hour.