Marvel Mystery Oil

[SaxMan]

I've always been kind of a skeptic with oil additives, especially when the last one I tried raised the oil pressure so high, it blew out the seal on the oil filter. However, I did get some Marvel Mystery Oil when I decided to attempt to start the motor on the '53 Plymouth for the first time (The Plymouth did start and run...that Flathead six is an amazingly quiet and smooth motor). I was so impressed with the results in the Plymouth that I decided to try it in the Sprite. Holy cow! The motor felt stronger and revved smoother than I ever recall. Maybe some of it was the perfect weather conditions - 70 degrees, sunny and dry, but I couldn't believe how much zip the car had today. 2nd gear runs up to 4500 rpm were a breeze.

Considering that the motor rebuild is on hold while I'm working on the Plymouth, this was a good development. My question is, how often do you put the additive into the oil? With each oil change? Considering that the Sprite has automatic self changing oil every 1200 miles, give or take another 100 - 200 depending on how long the car sits (I tend to lose more through leakage than through burning), I'd assume after I put the fourth new quart of oil since the oil change in, I'd go ahead and put in the additive.

 

[number6]

My only experience with MMO was at school. There were two Ford flathead V8s that ran the rope tows and at the end of winter MMO was used to fog the motors down for storage. I think modern oils have all the additives needed. I also don't think that MMO is a VI improver, I am guessing it may very well thin the oil. I also remember seeing MMO used as a Top cylinder lube. People would mount a glass bottle of the stuff in the engine compartment and it would drip feed into the carb manifold to lube the valve gear.

 

[JPSmit]

I've always been kind of a skeptic with oil additives, especially when the last one I tried raised the oil pressure so high, it blew out the seal on the oil filter. However, I did get some Marvel Mystery Oil when I decided to attempt to start the motor on the '53 Plymouth for the first time (The Plymouth did start and run...that Flathead six is an amazingly quiet and smooth motor). I was so impressed with the results in the Plymouth that I decided to try it in the Sprite. Holy cow! The motor felt stronger and revved smoother than I ever recall. Maybe some of it was the perfect weather conditions - 70 degrees, sunny and dry, but I couldn't believe how much zip the car had today. 2nd gear runs up to 4500 rpm were a breeze.

Considering that the motor rebuild is on hold while I'm working on the Plymouth, this was a good development. My question is, how often do you put the additive into the oil? With each oil change? Considering that the Sprite has automatic self changing oil every 1200 miles, give or take another 100 - 200 depending on how long the car sits (I tend to lose more through leakage than through burning), I'd assume after I put the fourth new quart of oil since the oil change in, I'd go ahead and put in the additive.

I might spread it thinner than that. I use Lucas oil stabilizer but only during oil changes - I top off with regular oil.

My concern is that is you start with 75/25% oil/MMO mixture and then add a quart of MMO - you will end up (at least in that cycle) with 25% MMO (the quart) plus 25% (2/3 quart MMO (of three quarts) remaining in the crankcase) - at which point you are about 40%(?) MMO.

So, to my mnd, either, 1. only use it when you change the oil or, 2. make yourself a mix of 75% oil/ 25% MMO and use that to top off the crankcase.

 

[Sarastro]

I think it is indeed good to be a skeptic regarding additives, and I'd include MMO in that skepticism.

The people who formulate motor oil put a lot of knowledge-driven judgment into decisions about what components to use and how much of each. There are trade-offs in each decision. For example, an additive might make the engine run smoother, but above a certain concentration might cause problems, so its concentration must be limited. When you add an additive, you upset that whole apple cart. I don't doubt that some particular additive (like, MMO) might make the engine seem to run smoother, but what about all the other things oil must do, like preventing wear and corrosion? How does it affect those? You really don't know.

I'd use a good-quality name-brand oil in 10W-40 or 20W-50 grade, and leave it at that.

 

[westfield7]

I've always used it when I change the oil in the spridget gearbox. After I've drained the oil I run a pint or so through the 'box. I pour it into the box at the shifter housing and leave the drain plug out. When I raced that was always good to get a few extra bits of metal out.

 

[mightymidget]

MMO is used in all my gasoline power lawnmowers etc.. Ran it in a Club Cadet for probably 20 years. Also I have used the Lucas in some older cars.
Really can not give any scientific figures, all I can say since I was a kid 60 years ago it has always been for sale at hardware stores, parts houses, truck stops. Just saying.

 

[mightymidget]

Forgot to mention in above post that I added it to fuel, not crankcase like the Lucas product.

 

[Joe Schlosser]

I Love the idea of a final flush of the trans by running light oil through the shifter housing. I will have to try it on my just rebuilt trans.
My previous technique was to fill and then tilt the trans up till I got flow out of the shifter and then let everything drain. This seems much better.