Does Marvel Mystery Oil Actually Work? Johnson Engine Part 5 

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

we're gonna test that - project farm lol

😆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. 😎👍

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

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.

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

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

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

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

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 👍🏻

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

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.

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.

I had this identical motor as a kid on the Rogue river in Oregon. I think mine may have been an 8 or 10 horse but maybe not. Otherwise everything about it is the same. My dad's motor was attached to an old wood boat with aluminum metal skin. I'd go upstream till I reached a rapids I could not get past. The boat would just stop in the current. I got used to rock locations to avoid sheering the prop pin. Which I did many times. I cut nails up to the pin length used many. Had a can of them with me at all times. My dad would take the boat out with a buddy and always sheer the pin cuz he didn't know where the rocks were. Memories...................

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

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.

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.

Your videos are great to watch. Marvel Mystery oil is excellent additive to use to lubricate engines,if stored a long time, rusty,dirty,gummed up. Use in Gas and may help clean internal parts. It's is not overhaul in a can as most additives included. I have used it for many engines

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

Stuffs great for cleaning engines

As a kid, my dad had his grandfathers Johnson just like this one. My father bought a boat and took me and my grandfather fishing many many times in that boat. The handle ended up getting broken off, but I sure remember that engine. I sure thank you for these videos. I sure wish I had that motor still.

I add Marvel Mystery oil a couple times a year to the air systems on my lowboy trucks . It seem to keep the air valves working nicely . I add maybe a shot glass full , in the line behind the air drier . If I have a sticking valve on a trailer , just our some in the glad hand . I am a solid fan of the Mystery oil !

Glad to see another video with you and your Johnson!

You get a like just for the "We're gonna test that" quote!

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

I bought a $5 lawnmower at garage sale that smoked tremendously. I changed the oil and added some MMO plus put fresh gas in with a bunch of MMO in it. Ran it for a about a half hour with it smoking when all of a sudden it stopped smoking. Ran that cheap lawnmower at my hunting camp for years and it always ran great.

That’s an idle exhaust relief. Typically, cooling water exits with exhaust to cool everything.

Have you ever tried any "Engine Restore"? I am very skeptical of miracles in a can, but a friend talked me into trying it in an old 3 cylinder diesel engine on a small utility tractor. I was as shocked as anyone by the results. The engine quit smoking so much and ran a lot smoother than it ever had for me. I ran the thing for another two years, dumping in another can every time I changed the oil. I sold it a few years ago and it is still running strong with no smoke out the exhaust yet. I'm still amazed by the difference in the engine.

I think with continued use, the rings will loosen up more as well as reseat themselves to the cylinder walls and it'll just run and run and run just fine.

How would you like to work on my Johnson? But anyway I do have the very same model. I'm glad I found your videos on this. I'm planning on trying to get mine running again..

That bucket looks like a hallowed cauldron with the engine being cooked in it ;)

Setting those points with a feeler gauge is just a starting point. Use a multimeter to fine tune them and set the timing on the firing correctly. For years, I didn't know that, but once I figured it out, these old motors crank much easier and run much smoother. Google will tell you the procedure. As far as the compression, those numbers aren't a deal breaker. They will still run fine with those numbers on that size engine. Also, run a couple of tanks of gas through it and see if those numbers improve.

"We're gonna test that....." Shades of ProjectFarm. :) Hahaha!

It’s funny as hell looking back on these old videos

I'm 64 and have seen MMO over the years and never used it until about 20 years ago when I used it in my son's truck that had a lifter tick it worked great I just used it about a year ago again for my Tacoma which was using oil between changes dumped a quart in and changed the oil at one thousand seem to fix the problem

My brother had a 318 Mopar and put 340 heads on it gave it 75 psi compression it could idle so slow you could count the fan blades. It ran great. I had a set of 401 heads milled so much the cranking compression was 185 psi it ran great. I've seen newer Mazda engines with over 230 psi compression. it's all bore stroke and combustion chamber volume.

I erased one comment on the rebuild in an earlier video, but I am back at it. First off your videos are great and thanks for the entertainment. The obsession over compression on this motor I believe is misdirected. From what I saw of that video your rings and cylinder walls were fine. For the most part I think you have not yet rightly adjusted the carburetor high and low circuits.The assumption that the brass crank bearing/seals are ok per visual inspection can bite you. Those small displacement engines have precious little tolerance for loss of crankcase pressure so those bearings and the seal of the crankcase halves is super critical. The cross hatching on the cylinders is primarily to enable ring seating...a wearable surface....and to retain lubricating oil to adequately lube the piston and cylinder sliding surfaces. The absence of cross hatch does not necessarily equate to low compression. I would not have been surprised to observe that a simple increase in two cycle oil ratio would have bumped up compression, that oil is the critical last factor to perform the seal at the rings and the crankshaft bearings. This test of Marvel M.O. is a bit off base, MMO has its application where it removes sludge and dirt that are sticking rings and other sliding surface parts, liker lifters and associated valve train parts, so I absolutely do not see a use for it with this outboard. Any liquid into the spark plug port "may" have the effect of a compression increase but it is not proving anything in this example.

never thought I'd enjoy a video series of a man messing with his Johnson

That's a pretty versatile Johnson.

Looking forward to #6 of Johnson series. No pun intended. ;)

I think many of us like watching you work on your Johnson. I understand you don't want to tear it completely down butt... You have spent a lot of time trying this and that. Maybe it's time to get a hold of some rings and replace them. LOL, or perhaps make some rings some how! I'm guessing new rings aren't going to be easy to find.

Well you no what they say try,try,and try again you will get it started eventually and it will run nice and smooth, have you heard of sea foam that’s ment to be really good you put it in the oil and fuel it cleans every thing out good luck looking forward to seeing it run properly

You could put a borescope down the spark plug hole and see if it is scored. Or take off the head and see. Also you could just replace the rings and pistons if needed and hone the bore.

I use Marvel in crank case oil (small engines) before changing the oil. Also use a bit in the fuel if it's not sounding right. I use it most as an air tool oil and in 25 years have yet to pooch an air motor, even on cheap Chinese stuff.

We’re gonna test that!

The smoke screen produced (engine fixes in bottles and can),is perfect for evading Fish and Game officers on the other hand.

I was a boat mechanic for 4 years. Any other oil with a high viscosity would do the same thing if applied the same way. It tells me don't believe everything you read on the label!! The only that really improves compression is removal and cleaning or replacement of the rings and or pistons. If a cleaner removes the carbon from the rings and they loosen up, compression will improve. These old two stroke engines often used a 20:1 oil mix and carboned up quickly. Often the transfer ports got the bulk of carbon, clogged up, and the engine would not breath right. boiling out the engine in a hot dip tank solved that problem. Eventually newer 2 stokes went to 50:1 mixes. All the newest outboards seem to be 4 stokes and believe me they are far more reliable. I can say for sure as a tool & die maker that Marvel Mystery oil mixed 1/3 with motor oil, and 1/3 Kerosene makes a great thread cutting lubricant and cutting oil in many applications!

If the rings are not worn out and still have some spring rebound to the you might try to add a bit of kerosene just a cap/teaspoon or so. If it frees your rings make sure to try and recover the MMO and kerosene it may be in the exhaust area.

I think Wayne Carini from Chasing Classic Cars loves dumping the Mystery Oil into old engines on the barn cars he finds. Seems to do a good job making so they can turn the engines over after they've sat for years.

in youre earlier episodes i commented on my Dad buying one of those back in 1963 and it ran great outside the waterbarrel meaning rings were bad shure enough the guy he gave it to reringed it and new head gasket and it ran all day

Marvel Mysterian Oil (96 tears) is a useful light oil in general. I use it in many areas.

Hold throttle open when checking compression

Not sure if you have a compression spec for that engine, but I had a 1998 225 Evinrude/Johnson saltwater series. When I did a compression check all 6 cylinders were around 90 psi. I panicked until I saw the specs called for less then 100 psi new. So going back many years in technology, I wouldn't be surprised if that old Johnson had fairly low compression to start with. If it runs the way you want, I would be concerned with taking it all apart and risking not being able to find parts that are inevitably going to break.

Count yourself lucky your Johnson still works at that age😊

Unfortunately as you rJohnson gets older, it will lose some power and the pistons will not produce the power that it once did as a younger model...Keep it up, your efforts seems to be working with the help of others. 🙂

I think you can add the Marvel Mystery Oil to the Gas too, that way a little is present in the Engine the whole time it is running. Might help a tiny bit.

John get a borescope type video camera to drop down your cylinder then look for vertical scratches, Chickanic u-tube girl uses this all the time when diagnosis on small engines, these are less than 100$ and really useful.

Those old motors were around 90 psi wet from the factory 60 psi would be your bottom number. Probably around 300-500 RPM's. It should also be 25:1 oil ratio so it was a drinker of oil. Another thing to consider is if you run it in a tub like that run use a fan. The exhaust from the engine will choke it out think fuel/air mixture.

That engine has a "few" miles on it its safe to say. Cleaning the carbon off of very worn rings will actually lower the compression. After the good cleaning achieved by both of these products, it's time for a good dose of RESTORE ( 1/2 0f the 4cyl treatment size ???) If you're going to rebuild it anyway, it be interesting to see the results. It does work on 4 stroke engines. Buddies 300,000 mile old Saturn, gets a dose every year now and still improves the compression enough to run surprisingly well. I believe in MARVEL Mystery Oil in the fuel too, to get at the rings from the top when the engine is hot.. Interesting Video 👍Thanx; Jethro

Sisyphean patience and almost Lokian humor. I like it, thanks.

Saw this exact motor sitting outside a dockside restaurant in Tacoma being used, (along with several other brand engines) a decorations. It looks intact. It caught my interest because of your videos on this one. Could be good source of parts for you.

i've used it many time, not sure if it helped but it didn't do any harm

Love the nods to AvE and Project Farm!

I suspect an engine that old has reeds between the carb and crankcase housing in Lieu of intake porting. Had an old Elgin 1.5 HP that had reeds and they go bad over time. Put some MMO in the cylinders with them vertical and slowly rotate the crank pulley to work oil around piston rings.

Acts like Seafoam. Used it in my Mercury car. I sprayed it in the carburetor, and it wanted to stall out the engine. Black s.oke came out the tail pipe, and the engine roared back to life. Still use it on my small engines. I bet it's a lot cheaper than Johnsons.

How many times am I going to watch you play with your Johnson, it’s not strange at all.

I've always thought about the lyrics🤔 To Deep Purple song "SMOKE ON THE WATER" Now I understand😁😎 And I really like your videos!

i love your videos and I love the G rated AVE “Johnson” in a vice comment! Keep up the great work!

"We're going to test that" Ahhhhh Project Farm LOL ... Nice work! :)

The compression on these engines is low so they can use low Octane fuel. Did you find a specification from OMC on what is ok?

6:30 I'm pleased that you realized that it wasn't a fair test unless you ran the engine, that product should be renamed Marvel Mystery Snake Oil!...... Your Johnson rings are knackered!

I love the smell of 2 stroke early in the morning on a lake!

I used it for years, the thing about engine bore and rings, a thing called metal gone, even marvel can't fix that.

Late again sorry: Best “ mechanic in a can” is actually a product by Johnson evinrude bombardier called “Engine tuner” follow directions on can. It will give you the best shot at freeing carbon stuck rings. It also works great as a carb cleaner. Disassemble carb throw all jets and small parts in carb bowl fill with tuner, soak overnite , amazing. It of course will not cure worn or damaged cylinders. Clearly that’s your case. As I finish typing this you bring out “ the tuner”. LOL

Never fail to chuckle at the Johnson jokes!!! 😁

It does seam low for compression, but at the same time it’s not too bad this is an older motor and lower compression is easier to start. I’ve rebuilt a couple power heads and they was at 90-100 but they where newer engines than yours

Came here for the Johnson jokes 😂

My dad said don’t ever use that stuff because you might loosen up the stuff that’s holding the engine together

Marvel is good stuff ive used it with great success . try adding it to gas with seafoam too . also good to fog 2 n 4 cycle engines . also avoid cheap 2 cycle oil . manufacturers oil is hard to beat . 40 yrs plus experience is all i have to go by.

Try this. Using Klotz part #200 at a mix ratio of 32 - 1. This will get rid of that smoke. For fuel use recreational fuel. The carbon will not build up in the engine, also that fuel will not damage rubber parts in your fuel system. Most all my engines gained compression. There ya go!.

It just doesn't get old, does it? lol But here's the big question: Why have Johnson innuendo? It's an Outboard motor for use in the Outdoors. Wouldn't outtuendo be more apropos? Or perhaps innueoutdo, because it's in the outdoors? As for keeping your Johnson in a vise: I'm guessing there are too many that the Johnson IS the vice! And a free word of advice: do NOT give the old ring(s) to the wife/S.O. I have it on good authority (I can't say how) that a woman does NOT appreciate a second-hand ring (not that any of these went on a 1st hand, but nonetheless). Namaste

Ave and Project Farm, Both I watch as well. lol Nice

You have a really nice Johnson!

I don’t quite understand why you wouldn’t expect the engine to have higher compression wet. It was designed to be run wet. It gets its lube from the fuel❤ going into the cylinder

If ever you have a loose piston or sparkplug covered in carbon try, soaking them for a week in MMO and see if theres any visible difference! Good luck...

Rings and a hone. Hopefully there is no significant damage to a cylinder wall (doubtful).

i remember we used redex on a volvo amazon. and the ring loosened up over time and it stopped sucking oil in to the cylinder's and stopped smoking after going downhill. the compression was not a isue on this and it was not measured.

Your outboard motor has been sitting Idle for ages so i think that the rings have lost their stiffness (that's what i think, i could be wrong !!)

Don't you need to defeat the pressure relief mechanism before doing a compression test ?

I’m not a rocket scientist, but isn’t the throttle supposed to be wide open?

"as high together as I can get them..." Sounds like California to me... Just a guess...the two holes are for water pump bypass...???

My dad used to use that in everything!

your engine appears to work fine

You can do the same thing with the Marvel Mystery Oil by adding hit along with your 2-stroke oil to the gasoline.

Piston rings spin so could be the rings are sticking, that would affect ur compression

When are you gonna do the rings?

Definitely gotta call this series "only-Farms, playing with my old Johnson"

Where did you get the rings for the pistons

Is the throttle wide open?

It's telling me the rings are starting to fail... You might also have a small leak in the head gasket...