Marvel Mystery Oil

It's a mystery to me.

 

MMO is a top cylinder lubricant, follow their directions and add to your fuel tank at fill up time. Helps to lubricate the piston rings and intake valves. Does not promote carbon buildup. Old school fuel additive from the 1920s.

 

A lot of people swear by it, especially there higher model vehicles. It seems to help with knocking and excessive oil consumption.

love it or hate it

 

Used to use it as a part of engine diagnostics, compression reads low even with a couple drops of engine oil, poor some of this in the plug holes and turn the engine over by hand, plug it and let it sit for 12 to 24 hrs, crank it over by starter with the plugs out for about 30 seconds, recheck comp readings several times on each cylinder if the comp number goes up and matches rings were stuck, if the comp number only comes up a couple of pounds, check valves. All that is good, needs a rebuild.

This stuff works.

All the trolls will be here shortly to state none of this works, snake oil, etc.......wonder if they believe in showers using soap?

Anyway, back the regularly scheduled thread....

 

I've used the stuff in the past. I haven't seen any miracles but it has cleaned some stuff up from time to time.

I do have one warning. IF used in the engine oil, make sure to keep an eye on the oil level. MMO WILL burn off as it has a low flash point, it is what it is designed to do.

 

My old '94 Ranger had a noisy lifter in colder temperatures (sounded like a machine gun on a cold start). If I added a quart of MMO in place of regular oil, the noise would go away, and I did this for years. I think it's a great product.

 

I had a P0420 and it turned out to be the donut gasket connecting the cats to the Y pipe. Twas a very small leak. After several trips under the truck I finally noticed a small, barely an 1/8" wide soot mark at the joint.

I'm not saying that your exhaust is leaking, just sharing my experience that my exhaust leak was tiny and was easily overlooked.

 

A freaking 6 pack! Verrry nice. Still running points? Lol

 

NOPE !

 

I would have been shocked had you said yes. I don't miss those days.

 

My dad used to pour it in everything he had.

 

Agree! I had two kids vehicles with engine knocking and used one quart of this with regular motor oil. Knocking stopped and car ran way better with more pep. I use half to one quart now at least once a year on all my vehicles. Honestly SeaFoam is my go to before every oil change and that stuff really works.

 

Same, same as taco forever, but not quite 40 yrs. I am well schooled and live in Boston. I understand chemistry and how properties work. I cannot explain how or why Marvel mystery oil works, but it does. My grand daddy did so too and told to do the same.
From trucks to BMWs to Italian motorcycles, I have done the Full 1 qu are swap and into the fuel line. when something works without fail for so many decades, I don’t bother asking too many questions. I just do it.

 

Holy Christ, my pants just flew off!

 

To this day my grandfather still drink a shot of MMO every morning. He is retired Caterpillar mechanic from the 50s.

 

No whale bubbler like the original mmo

 

I tried adding it to my fuel at every fillup for a few tanks. I wound up getting a miss-fire, once I stopped using it in the fuel the misfire went away. Just my experience, I believe all the others who have had great success with it.

 

I’ve never added it to my fuel and probably wouldn’t I do use it in my 95 Corolla but I don’t leave it in there for long. I wait until I’m close to an oil change then add the recommended 20% to the crank case after draining out the appropriate amount obviously then I take a little road trip about 75-100 miles each way to give it time to heat up and just run through the system for a while without interruption. After that I go ahead with my oil change. I do this once a year or so and the older engines really seem to like it.

 

I use Sea Foam additive in my fuel. Especially on road trips. It really boost MPG's and smooths out throttle response.
Marvel Mystery Oil, I use all the time at work. I lube practically every treaded fastener with it. And forget PB Blaster. It's OK, but try using MMO. Work it into the rusted part with a toothbrush and you'll be amazed how it penitrates rust. Living in the northeast where salt is my enemy in winter, I've had plenty of experience dealing with rust.