Marvel Mystery

[RHuff]

Anyone use it in their outboards? I'm in the process of getting a 1991 Bass Tracker TX 17 with a 40 HP Mercury. Since it is an older boat I thought about adding a little Marvel Mystery to help clean out everything and to help it run smooth. I've used it in my truck, in my atv, in a lawn mower, in a weedeater, and thought about trying it in my boat, but thought I'd check anyone elses experiences first.

[thomas15]

Personally I always use an ethanol stabolizer, the Mercury brand Quickare #1 is available at Walmart for about 6 or 7 dollars and treats 150 gallons. When you get ready to put your boat up for the winter your fuel system will be protected and all you will need is to fog your motor with something like Seafoam. The TC-W3 2 cycle oil you will use does a good job of protecting the moving parts. If you start out with a clean fuel system, use good fuel and maintain everything and use your boat enough to keep fresh fuel in the tank and carbs then you really shouldn't have any problems with the fuel delivery system.

 

Now that I have my fuel system working properly and the motor adjusted correctly (took a while) it is a joy to use (mine is a 2005 Mercury 50 HP). Just so you know, most if not all of the 3 cyl Mercury 2 strokes are not the smoothest at idle or slow speed. Nature of the beast. No additive is going to smooth out that idle!

[BaitMonkey1984]

There is nothing I do not put this stuff in. In fact, my Father always gives me a hard time because if I have an engine problem I always say it isn't anything a little marvel mystery oil can't fix.

 

I have 2 cars, 2 boats, and lots of other small engines. I use this religiously in everything. The oil cleans out as well as lubricates. In my outboards, I specifically use this, seafoam, and the star ton enzyme treatment every fill up. My  2001 150hp yamaha; an old 7.5 hp game fisher (RIP poor outboard I retired that this year); and a 2007 8.0 hp mercury engine is always clean and run like a dream. It isn't cheap, but it is easy and it is certainly cheaper than another marina bill.  Put this in everything. And by everything I mean I put some in my gas and some in my oil for my two stokes. Literally, everywhere!

[bigbill]

I use seafoam it's a fuel stabilizer, lubes the valve stems, seats, frees stuck rings, reseats the rings. It's in all my equipment every spring / winter.

In all my power equipment, mowers, tractors, garden tractors. Everything starts up in the spring like I never stopped running it.

[Way2slow]

Marvel Mystery Oil is suppose to work good in a crankcase to help free sticking lifters, valves etc, but I can't remember ever having used.  Not too sure how it would work as a gasoline additive where it is being burnt in and engine.   In a two stroke, you want something that's going to help remove carbon deposits in the combustion chamber, don't know if MMO would do that, or actually increase the amount of deposits. 

 

  I have gone through cases upon cases of SeaFoam and has always been my go to product.  It will flush a crankcase and clean lifter if needed.  It will stabilize gasoline and it will help remove carbon inside two stroke engines.  I've always figured, if it ain't broke, don't need to fix it and SeaFoam has always worked for me.