Marvel Mystery Oil, 1gal

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Marvel Mystery Oil, 1gal

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Item Description

Marvel Mystery Oil cleans and lubricates fuel injectors and carburetors. It reduces and prevents varnish and gum build-up.

Marvel Mystery Oil, 1gal:

  • Positive lubrication for smoother starting and longer tool life
  • Dissolves gum and sludge that cut down tool speed and power output
  • Prevents rust and corrosion
Safety Alert: Due to federal restrictions, this item must be returned in its original package, or with secure ORM-D packaging obtained from the post office. We advise keeping the original packaging for at least 90 days. See our returns policy for more information.


Model No.: MM14R
Shipping Weight (in pounds): 7.7
Product in Inches (L x W x H): 7.38 x 3.88 x 10.88
Walmart No.: 001040638

Customer Product Reviews

Rated 5 out of 5★áby 11reviewers.
Rated 5 out of 5★áby Most trusted and reliable product!!! I work on alot of small engines for a hobby. I also fix and maintain alot of my friends and familys cars. Used alot of additives for the fuel and different oil additives to. (lucas, stp, bardall, tech, etc) But none of them can ever compair to MMO!!! I revived ALOT of mowers, weed eaters, snow blowers, and even vehicles by using it in the oil and fuel. Does a great job cleaning all the carbon out of the injectors, carb, and crankcase! Also it is absolutally a FABULOUS product for preventative maintnance on a car! I only use quakerstate semi-synthetic (conventional mixed with some synthetic) motor oil with a quart of marvel mystery oil. even after 5,000miles when i change it the oil is suprisingly cleaner and holds its viscosity WAY better than full synthetic motor oil!! It was such a great additive that you will find out that in world war 2 the USA and the British used this product in all of their tanks, fighter jets, and carriers! If its that good of a product that even the army uses it and it held up in battles its great enouph for my car! Also its made and packaged in the U.S.A!!! SWEET! 04/22/2012
Rated 5 out of 5★áby ENGINES BEST FRIEND Have been using MMO for 50 years, both in the crankcase and the fuel tank on all my vehicles, cars and trucks new and old. best performance product I ever used. 06/08/2012
Rated 5 out of 5★áby Marvel Mystery Oil is the best product for both gas and oil I have ever used. My engine runs smooth and it idles better than ever. I have use the product for about a year and with WalMart pricing I am able to add to my gasoline each filling. 02/27/2012
Rated 5 out of 5★áby MMO works great in airplanes! I have an STC to run ethanol-free auto gas in my airplane and like the previous owner did for over 20 years, I use 2 oz of MMO in every 10 gallons of fuel and also add a pint in the oil during every 50 hour oil change. During a recent 1,800 hour interval overhaul of the 33 year-old Continental O-200 engine the A&P mechanic said it looked like a near factory-new engine on the inside. It probably could've gone another 1,000 hours before really needing the expensive overhaul. 01/23/2013
Rated 5 out of 5★áby Excellent product Helps with gas mileage and oil viscosity. I have been using MMO for over 40 years. Engine runs smoother and longer in each vehicle I have ever driven. 05/19/2014
Rated 5 out of 5★áby Awesome product Marvel Mystery Oil is as useful now as when it was originally introduced. This fuel/oil treatment is as good as it gets. It improves my gas mileage while drastically reducing the wear on my engine components. With a better seal during combustion not only do I have more power and greater mileage, my oil changes are less frequent as I have less particulates in the oil. I have never had any gas treatment work as well as this one. 05/01/2014
Rated 5 out of 5★áby Preventive Maintenence I have been using Marvel Mystery oil for years in my garden tractor, tiller, pressure washer, weed wacker and I add it to the fuel every time there is no better product it does exactly what it says. I have found that Walmart is the best price for 1 gallon and no one has is at a better price. 05/30/2014
Rated 5 out of 5★áby beenusing for years been using for years 05/18/2014
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