Anyone recommend Marvel Mystery Oil?

[El Capitan]

Both for engine oil and fuel additive.
Got an ole mercruiser 350. Good compression. But looking to extend life of motor and fuel system.

Let the rumble begin.

 

[scoflaw]

Snake oil. Has its uses but won't extend the life of anything

 

[Soulshine]

I put it in the same mental category as Seafoam. Enough people swear by them that I'm open minded but I've also never used either.

Probably snake oil.

 

[Soulshine]

You'll extend the life of your engine by doing regular changes using quality oil and filters.

I'm guessing you're already doing that.

 

[370Dancer]

Used it to loosen stuff up in the Yamaha AR190 after the engine went under during hurricane Irma. Took 2 months but I got it back. I had nothing to lose.

 

[Scott215]

I'm a true believer in it I add to my boat fuel all the time when I fill it

 

[sfergson727]

Multiple airplane mechanics I use swear by it, I trust their judgement.

 

[Halfhitch]

I think it's good stuff. I had a lifter in my chev truck that was always ticking. A mechanic at the company I worked for told me that if, on my next oil change, if I would replace one of the quarts of oil with a quart of Marvel Mystery Oil that ticking would go away. It did. That doesn't mean it is going to make a worn out motor be not worn out. It's a good light oil for lubing all manner of working joints, pins, bushings and other linkages. I have a thumb can that is always holding MMO. Another great attribute is, it smells really nice. I may try some on my pancakes next time.

 

[Scott215]

You have to get something to lubricate the fuel and the upper cylinders,fuel pump ect. No lead in most fuels now so it's always in my boat

 

[Scott215]

Yummy

 

[Skybolt]

I always ran Lucas oil and gas additives in my gas engines and had great success. I had crusader 454's that had over 2200 hrs on them and still had great compression and ran like tops.

 

[scoflaw]

I think it's good stuff. I had a lifter in my chev truck that was always ticking. A mechanic at the company I worked for told me that if, on my next oil change, if I would replace one of the quarts of oil with a quart of Marvel Mystery Oil that ticking would go away. It did. That doesn't mean it is going to make a worn out motor be not worn out. It's a good light oil for lubing all manner of working joints, pins, bushings and other linkages. I have a thumb can that is always holding MMO. Another great attribute is, it smells really nice. I may try some on my pancakes next time.

A quart of ATF would do the same thing I had the same problem

 

[GirlyGirl1999]

I echo halfhitch, my Dad always had a squirt can of it, we used it on everything. I have a bottle but I only use it for the mower, start of the season, new plug and while it’s out about 1/8 cup down the plug hole, pull through twice, plug in, mower starts instantaneously. I hand the mower off to the Queen and my work here is done. I have never used it in fuel, I’m a Lucas guy as well. I do have a squirt can full as well though.
My .02
Jon

 

[jmauld]

I put it in the same mental category as Seafoam. Enough people swear by them that I'm open minded but I've also never used either.

Probably snake oil.

Sea foam cleared out an engine code on a recently purchased rx8. I won’t claim it works for anything else but it did loosen up the valve that was sticking and throwing that code.

 

[El Capitan]

Ok then. I’m using it. Thanks everyone!

 

[Flyer5]

It is one of the few "Mechanic in a can " type products that actually has some merit. Great for diesel injectors, stuck lifters and rings from carbon maybe a few other uses.

 

[Halfhitch]

Now if Marvel can figure out their marketing so they can charge what Yamaha charges for ring free, they could start smoking better cigars.

 

[Brite Idea]

Switch to synthetic oil would be the way to go.

 

[Scott215]

I use factory merc 25 40 semi syn. Still use marvel in fuel only

 

[highslice]

I have used Rotella 25 40 full synthetic for the last 10 years. Nothing else needed.