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Marvel Mystery Oil  Oil and Fuel Additive 118712
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  • Part #: MM12R|
  • SKU: 118712

Available tomorrow

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    • Helps improve fuel economy
    • Cleans and lubricates fuel injectors and carburetors

Marvel Mystery Oil Oil and Fuel Additive

Since 1923, Marvel Mystery Oil has helped increase the life of countless engines of all types. Marvel Mystery Oil cleans the engine from the inside out while increasing fuel economy and protecting against temperature extremes. Regularly use Marvel Mystery Oil in your oil and fuel to enhance overall performance.
  • Helps improve fuel economy
  • Cleans and lubricates fuel injectors and carburetors
  • Reduces and prevents varnish and gum build up
  • When added to oil, prevents valve sticking and clatter
  • When added to oil, prevents oil breakdown caused by extreme temperatures
  • This item must be picked up in the store as it may contain materials which are flammable or corrosive.



Marvel Mystery Oil Oil and Fuel Additive is rated 4.7 out of 5 by 58.
Rated 5 out of 5 by from Great product! I have used this for some 40+ years on all types of engines. I use it primarily in the gas tank as a top lubricant. I have put 100000+ on at least 6 vehicles and my current work SUV a 99 Dodge Durango with 145000 runs well. I have also extended the life of several mowers with its use!
Date published: 2014-12-16
Rated 5 out of 5 by from Marvel Mystery Oil Seems to help my engine
Date published: 2014-12-16
Rated 5 out of 5 by from Marvel Mystery Oil I have been using this product for over twenty years now and have never had a problem with using it yet. A great product for gas additive and oil additive. Will never stop using it. Buy some and try for yourself.
Date published: 2014-12-09
Rated 5 out of 5 by from Excellent as usual Great for your oil and gas - takes all the knocks out in your engine. - smooth ride
Date published: 2014-12-05
Rated 4 out of 5 by from Marvel Mystery Oil My older low compression aircraft engine needs MMO to prevent valve guide problems.
Date published: 2014-12-03
Rated 5 out of 5 by from THIS PRODUCT IS the best fuel and oil adative on the market I HAVE USED MYSTERY OIL IN ALL OF MY HISTORIC HIGH MILAGE VEHICLES ALSO IN MY 100.000 MILE OR MORE ENGINES AND THEY RUN LIKE NEW CARS.I AM AN AUTO MECHANIC AND I SWEAR BY THIS PRODUCT IT DOES TWO THINGS FOR ONE LOW PRICE. Also works in small engines even outboards. Put half in oil and half bottle in gas tank. You will see a difference.
Date published: 2014-11-29
Rated 5 out of 5 by from It works! I have added Marvel Mystery in the past to the oil during new engine breakins. This time have been adding it to the gas in a 1995 Toyota Land Cruiser with 233,000 miles on it when I bought it. Have logged additional 1800 miles since, and the engine just keeps running better and better. Better pick up, throttle response, etc. Have also been passively desludging the engine and will put MMO in crankcase at next oil change.
Date published: 2014-11-22
Rated 5 out of 5 by from Marvel Mystery Oil Excellent product.. Have used it for years. It has increased car mileage.
Date published: 2014-11-21
Rated 1 out of 5 by from Very useful product GREAT PRODUCT
Date published: 2014-11-18
Rated 5 out of 5 by from Marvel Mystery Oil is amazing stuff! I operate diesel vehicles (car and truck) and belief that this product has directly contributed to the longevity and smooth operation of both vehicle as a result. I recommend it to family and friends because it is an excellent product!
Date published: 2014-11-05
Rated 4 out of 5 by from owner first time worked ok would buy again and tell my friends
Date published: 2014-10-21
Rated 5 out of 5 by from Works great for freeing rusted parts & more I started using this to free up seized motorcycle engines that had been sitting for a long time. A few days of Marvel Mystery in the cylinders and it would break loose. I use it in my fuel tank and engine oil also to keep things clean.
Date published: 2014-10-19
Rated 5 out of 5 by from I love it!!!!!! Marvel Mystery Oil has been around for a long time and I'm just now hearing about it, WOW!!!!! Actually I heard about it years ago and paid it "No Never Mind"!!! Stupid me!!!!!! I use it as a fuel additive and WOW, my gas mileage has sky rocketed big time!!!!!If I had only known about this years ago...... Actually I did but no one ever told me how well it works. WELL I'M TELLING YOU NOW,IT WORKS AWESOME PEOPLE, AWESOME!!!!! Especially for the price. Hands down the best price for the money. And you can add it to your oil too. Go figure!!! Don't pass this one up people, trust me. I'm now 50 and have been a mechanic since I was 13. Trust me guys, try it and you won't regret it hands down!!!!!
Date published: 2014-10-17
Rated 5 out of 5 by from good for condiioning deisel fule same as above
Date published: 2014-10-09
Rated 5 out of 5 by from This product comes highly recommended by my motorcycle mechanic for loosening the spark plugs on my bike. Fortunately I didn't need it as the plugs came out easily enough.
Date published: 2014-09-15
Rated 5 out of 5 by from I use this in my 2 cars You must use this in your oil and gas tank for the full benefits. So far it lives up to my expectations. My Mustang loves it!!!!
Date published: 2014-08-22
Rated 4 out of 5 by from Good, but... I have two cars and do my own oil changes. I use synthetic oil in one with regular oil in the other along with a Qt. Of Lucas oil, cylinder polish, and recommended amount of Marvel. I found that with Marvel, my oil in both cars got dirty faster[the cleaning effect]. From now on I'll just use a little in the oil and use more in just gas.
Date published: 2014-08-21
Rated 5 out of 5 by from Magic Oil I live off the grid and rely on a large and a small generator. The temperatures are now 107 degrees daily. I use heavy oil in my large generator to sustain the heat, but worry about lack of lubrication, so I mix the Marvel into the oil to reduce it just a little for extra lubrication. Additionally, I put the Marvel into the fuel of both generators and it improves the performance, fuel efficiency, and both generators run smoother than when they were new. Great stuff!
Date published: 2014-08-11
Rated 5 out of 5 by from Marvel Mystery Oil You know I had a top end rattle in the morning. I remembered the product from the sixties so put in a quart. Not only did it stop the noise, but the engine has quit using oil between changes. This stuff truly a mechanic in a bottle. Love the stuff. Dave
Date published: 2014-08-05
Rated 4 out of 5 by from the standard of additives both as an oil and gas additive has given my vehicles since 1964 a long engine life in all instances
Date published: 2014-08-04
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