Marvel Mystery Oil

[Ralph P.]

I've seen several recommendations for adding this product to today's gasoline. What do we think ? If so, why & in what mix ?

[Dick W.]

Re: Marvel Mystery Oil

MMO added to the gas would give you some additional upper cylinder lubrication. I am not sure that the modern engines need this additional lubrication, plus I would be concerned about fouling the O2 sensor and maybe the catalyic converter. Older cars, however I believe, could benefit from addition of the recommended amount on the can.

[Ralph P.]

Re: Marvel Mystery Oil

The question is related only to vintage engines.... Thanks

[Tom R.]

Re: Marvel Mystery Oil

Have you ever tried Bardahl Ohhh do they still sell it

[Roy V.]

Re: Marvel Mystery Oil

Have you ever tried Bardahl Ohhh do they still sell it

something called seafoam is supposed to be better than marvel mystery oil, though to be honest, I've never tried either one

[Michael W.]

Re: Marvel Mystery Oil

Anybody got any proof of any of them actually working on an SBC or a BBC? What problems do they fix or avoid?

[Dick W.]

Re: Marvel Mystery Oil

Sea Foarm works somewhat like Sta Bil as a fuel stabilizer. I have used MMO for many things in the last 50 years, such as freeing stuck rings in an engine that has been sitting for an extended perior of time, upper cylinder lubricant in older engines that had a habit of valves sticking after setting extended periods of time, has helped quitening hydraulic lifters. Also good air tool lubricant

[Steven B.]

Re: Marvel Mystery Oil

'Used MMO for "unsticking" engines that have sat for a few years. Let it "soak" for a few days to be careful.

Steve

[Valeria H.]

Re: Marvel Mystery Oil

MMO added to the gas would give you some additional upper cylinder lubrication. I am not sure that the modern engines need this additional lubrication, plus I would be concerned about fouling the O2 sensor and maybe the catalyic converter. Older cars, however I believe, could benefit from addition of the recommended amount on the can.

Dick, Are you suggesting adding MMO to the gas because of the ethanol content or because there are so many moving parts on the old engines?
Valeria

[Michael W.]

Re: Marvel Mystery Oil

Dick, Are you suggesting adding MMO to the gas because of the ethanol content or because there are so many moving parts on the old engines?
Valeria

I know Dick and am sure that he would not suggest anything of the kind be done to a Corvette engine. There is no need for this product or anything similar. These engines operate reliably for decades and generations WITHOUT any special additives, fuels or maintenance gyrations- and do so very frequently in spite of tremendous abuse and neglect inflicted by unknowing or uncaring owners. The SBC and BBC engines are about as bullet proof as they come in this respect.

Please do some research on what MMO or Seafoam is comprised of and what their original and correct purpose was, compared to the cure-all they're marketed as today. They will do no harm added to a tank of gas, but it's money wasted.

[Jerry B.]

Re: Marvel Mystery Oil

Hello Gents..What ratio would you recommend?

[Jim L.]

Re: Marvel Mystery Oil

'Used MMO for "unsticking" engines that have sat for a few years. Let it "soak" for a few days to be careful.

Steve

It absolutely works wonders for this purpose.

Awakening my '63 roadster which had sat unstarted for 15+ years, the engine would run reliably but poorly on several cylinders (more than 3, fewer than 6).

After adding MMO to the oil, the engine rapidly proceeded to empower most of its cylinders (7-1/2, or there abouts). The only reason it didn't bring back all 8 was that one piston and most of its rings were broken (unbeknownst to me at the time).

So, I'm a believer in the stuff in certain limited applications.

Jim

[Michael M.]

Re: Marvel Mystery Oil

Jerry I use a ratio of 4 oz. to every 6 gals. of fuel. I use the MMO in a 1966 327/350 engine. Never had a problem with fouling spark plugs. I also add a couple of oz. to my engine oil.

[Stuart F.]

Re: Marvel Mystery Oil

Dare I throw Wynn's Friction Proofing into the mix? We used to pack the cylinders of an engine due to sit for awhile. My 63 sat that way for close to five years and, when pumped out, valves reset, new plugs installed, it started right up and ran like a champ. Only problem was the start was made in 0 degree Wisconsin weather and the PCV valve stuck open allowing gas fumes to enter the crankcase during cranking which led to a crankcase explosion. Lost a set of original aluminum covers and a chrome choke tube on that day. Don't know the whys or wherefors of using the stuff back then, but that was what was commonly done. The engine still runs fine even today and has never been torn down.

Stu Fox

[John D.]

Re: Marvel Mystery Oil

Dare I throw Wynn's Friction Proofing into the mix? We used to pack the cylinders of an engine due to sit for awhile. My 63 sat that way for close to five years and, when pumped out, valves reset, new plugs installed, it started right up and ran like a champ. Only problem was the start was made in 0 degree Wisconsin weather and the PCV valve stuck open allowing gas fumes to enter the crankcase during cranking which led to a crankcase explosion. Lost a set of original aluminum covers and a chrome choke tube on that day. Don't know the whys or wherefors of using the stuff back then, but that was what was commonly done. The engine still runs fine even today and has never been torn down.

Stu Fox

PCV valve stuck open. Blackening PCV valves to get judging points is one way of having them stick open. Avoid blackening those valves if you can as it rusts the internals. Or cheat and tape the ends off to keep the chemicals out of the inside.