Does Marvel Mystery Oil Actually Work? Johnson Engine Part 5

My Johnson has low compression! Let's try both Marvel Mystery Oil and Johnson/Evinrude Engine Tuner to see if they help.

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Unfortunately with only 1 engine worth of data, there's no way to get a real answer as to whether the products work or not. They might work very well, just not in this case.

[charles]

'we're going to test that' im sure he appreciates the call out

[DIYBuilds]

we're gonna test that - project farm lol

[willykanos]

"Keep your Johnson in a vise" - Pure AvE. Good job.

[rjkStudios]

😆Paused viewing to say that I got a good chuckle out of the "we're gonna test that" reference. I've really enjoyed this Johnson engine series so far. 😎👍

[Angel_the_Bunny]

Whats this the 4th video? WE GET IT, YOU'RE PROUD OF YOUR JOHNSON!

[robrivait]

I have been watching your videos about this outboard, I have worked on a ton of these old johnsons and these were not very high compression motors to begin with straight from the factory. They were around 90 PSI per cylinder if you have above 70 PSI and they are within 10% of each other (the cylinders) the motor will run fine. Like I say I have worked on well over a hundred of these motors. These motors can be cranky when you do not set your low and high speed needle correctly. In a previous video it was only running on one cylinder, when you got it to run on both cylinders and it idled down as low as it did that is another telltale that your compression is fine. If the compression was too low that motor would not have idled well at all.

[huskywithcoffee]

I never thought I'd enjoy watching a man spend this much time on his Johnson this much!

[ToasterBath]

Keep your Johnson in a vise. Nice shoutout. Love it!

[colsoncustoms]

The “we’re gonna test that” had me a chuckling

[waynebaird]

I have an old Coleman 1700 watt generator. I got it quite old and used but it would run for 3 hours on a tank of fuel consistently. I started adding Marvel Mystery Oil into the fuel tank and the generator shockingly began to run for 7 hours on the same amount of fuel. I was a win for me. I like your Johnson. hahaha

[ohasis]

I asked my ten year old nephew what he thought about your mystery oil to which he replied 'nothing.' I asked him why not and his response - 'nobody knows, it's a mystery.'
I guess there can be wisdom in kids.

[maryellenrawlings]

I use it in cars that are running rough. It smoothes the engine and improves my gas mileage. I use it as a gasoline additive. Love it

[just-in-time]

One thing I've learned that any crankcase seal bad you will have issue also thanks to my uncle's that had a shop in pa built my first motor by 8 good old trail 90 was poor and my uncle's always had bike lay around and said I show u then use have something to ride when we go there on the weekends now in my 40s there nothing I wouldn't tackle and don't act like u no it all always take advice if there skilled I just came across your channel and had a old 25 hp Johnson and like the way u do thing and explain it.keep up great work and have a wonderful day.

[ricksnowden]

Hold throttle open when checking compression

[warrenmcardell]

The Marvel Mystery oil can be added to crank case, oil change on 4 strokes. Also in gas tanks of 4stroks & mixed with 2stroke gas. For a top silencer lube. I've ran it in my Dirt track race cars 4wheeler, dirt bikes, evey thing cars, trucks u name it. I believe in it 100% Also these are the best ways to get the better results & performance from the product. I enjoyed your video on cutting down the tree & plan on watching more 👍🏻

[Raggzzaug]

Did an experiment years ago with a Homelite weedeater. Used MMO instead of 2 cycle oil because I had a couple spare crank cases.
Used it for several years and never had a problem.
Got the idea from racing rotary engine guys that add it to their gas to protect apex seals.

[Deathbite]

We gonna test that.. I see what you did there ;-) One Farm greeting another one. Cheers from Germany

[marktrammell]

I worked on those older outboards for a few years back in the late 70's, and 60psi compression was pretty normal even after the engine cleaner was used. We used that engine cleaner on every one of those older motor that came in using the older oil/gas mix ratio of 16 to 1 before switching it over to a 50 to 1 ratio with Evenrude or Johnson outboard motor oil. That low compression is not a problem with the motor and allows them to idle really slow while trolling. The exhaust holes in the shaft are there to prevent the exhaust back pressure from killing the motor at low idle.

[AllisChalmersMN]

Glad to see another video with you and your Johnson!

[thedude]

I swear by this oil. As a certified stihl mechanic, this stuff has saved many people carberators.