Marvel Mystery Oil

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6319
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Marvel Mystery Oil

Post by 6319 »

The MMO container says you may add it to your OIL , up to 20% of the oil volume, so 1 qt in a 5 qt capacity. I'm wondering if anyone out there has tried this, also if they have flown with it. Just askin.
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Re: Marvel Mystery Oil

Post by 6643 »

I recommend you do not try it. MMO is primarily a solvent. Adding 20% solvents to your engine oil then running at 70% power or so just doesn't seem right to me. Also, unless you're running you sump at the full 5 quarts, 20% would be less than a whole quart.
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Re: Marvel Mystery Oil

Post by 6298 »

Back when I used to fly photos, from 9000 feet above the ground, I would get a little engine shutter and have to level off and cool down a little to finish my climb. Marvel oil cured the problem. I found it worked best in the fuel. I think I tried it in the oil first and noticed no difference.
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals
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Re: Marvel Mystery Oil

Post by 6319 »

Thanks Randy, I hope you were not affected by the Fires in CA.
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Re: Marvel Mystery Oil

Post by 6843 »

X2 for adding it to the fuel. Since I've started adding it every 3rd - 4th fill, I have had zero fuel valve problems and borescope shows clean intake valves
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Re: Marvel Mystery Oil

Post by 7429 »

I always use it as directed in the fuel. When I bought my 140 the previous owner who used it all the time said to use it or the plugs will be more prone to fouling with led deposits. My A&P said the same thing and uses it in his aircraft. I didn't buy into it after reading all the back and forth on the web. Then I started to have some cold misfires on plugs. Started using MMO in the fuel and the problem went away. I have also read that it can help the longevity of your fuel selector valve or help if it is a bit sticky. I have the original fuel selector valve and it works perfectly. Not sure that's science but MMO does no harm IMO. Wouldn't put it in my crankcase though.
1949 140A
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Re: Marvel Mystery Oil

Post by 8170 »

How much do you add to a full tank for it to be effective?
"Some people spend their entire lifetime wondering if they made a difference, the Marines don't have that problem"
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Re: Marvel Mystery Oil

Post by 6298 »

8170 wrote: Mon Sep 24, 2018 11:15 am How much do you add to a full tank for it to be effective?
4 oz. treats 10 gallons is what my bottle says
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals
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Re: Marvel Mystery Oil

Post by 8170 »

Thanks Randy
"Some people spend their entire lifetime wondering if they made a difference, the Marines don't have that problem"
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