Marvel Mystery Oil

[72and86]

Marvel Mystery Oil, ...has anyone heard of this stuff? My dad swears by it. You put it in the crankcase and or the gas. I think it even acts as a gas "stabil". Does it work? Or is it snake oil.

[mr.beachcomber]

Marvel Mystery Oil (MMO) has been around since 1923 in various formulations. The most common use is as an upper cylinder lubricant and carbon buster when added to the vehicle's fuel (gas or diesel). It has various cleaning agents and some kerosene although the wintergreen aromatic seemingly overpowers everything else.

WWII vets like my Dad swear by the stuff as the military applied it to everything as a lubricant, preservative, or engine oil additive. I sold a lot of it as a gas jockey in the late 50's and early 60's. (Made a nickel commission off each can sold. Quite a lot when the minimum wage wasn't even a dollar!) We added it to the gas and to the crankcase for our customers to break up carbon and oil sludge buildup common back then.

Some renown Chevy mechanics use MMO as an assembly lube for the pistons, rings, & crank. Others use it as an engine flush prior to changing the oil after initial break in. MMO seems to do this and much more w/o causing any problems.

I don't use MMO any more as engine sludging is a thing of the past with Mobil 1 plus Techron is a better fuel injector cleaner. Still, it wouldn't hurt if I inherited an old, worn out engine I wanted to revive.

Bottom line is MMO doesn't hurt, but all modern oils and additives are better. YMMV.

[72and86]

Originally Posted by mr.beachcomber

Marvel Mystery Oil (MMO) has been around since 1923 in various formulations. The most common use is as an upper cylinder lubricant and carbon buster when added to the vehicle's fuel (gas or diesel). It has various cleaning agents and some kerosene although the wintergreen aromatic seemingly overpowers everything else.

WWII vets like my Dad swear by the stuff as the military applied it to everything as a lubricant, preservative, or engine oil additive. I sold a lot of it as a gas jockey in the late 50's and early 60's. (Made a nickel commission off each can sold. Quite a lot when the minimum wage wasn't even a dollar!) We added it to the gas and to the crankcase for our customers to break up carbon and oil sludge buildup common back then.

Some renown Chevy mechanics use MMO as an assembly lube for the pistons, rings, & crank. Others use it as an engine flush prior to changing the oil after initial break in. MMO seems to do this and much more w/o causing any problems.

I don't use MMO any more as engine sludging is a thing of the past with Mobil 1 plus Techron is a better fuel injector cleaner. Still, it wouldn't hurt if I inherited an old, worn out engine I wanted to revive.

Bottom line is MMO doesn't hurt, but all modern oils and additives are better. YMMV.

Cool. Yes I have inherited a Vette (1979) w/ 109,000 miles on it. I guess thats a lot of miles for 1979 cars.