Two year old fuel

[matt167]

Seafoam is crap ( alcohol, pale oil and water ). However MMO does wonders for various things.. ~10 years ago I had a Rambler with the 195.6 engine and horribly burned valves. vacuum was pretty much gone. It would stall if the throttle was blipped too hard.. MMO every 400 miles down the carb throat brought the vac back to the point it became drivable..

As for what MMO actually is, well it's basically Naptha, which is a solvent. That's why it can clean varnish

 

[Damdan]

"BTW, you can also soak with MMO. In other words, pour some in the gas tank, then brush a little over the carbs and pour a half ounce or so into the intakes and a drop or so into the spark plug holes if you can."

I am not the expert and I know nothing about MMO because its not available where I live.
So im asking, is the above a good idea?
Can this MMO stuff not flow past the piston rings and mix with the sump oil?
And we know what happens when engine oil is contaminated.

 

[Dp59]

Now it's only a matter of getting MMO in Canada

Got mine at Princess auto but Canadian tire also has it.

 

[Mcfltfyter]

Can this MMO stuff not flow past the piston rings and mix with the sump oil?
And we know what happens when engine oil is contaminated.

Considering they say you are supposed to add it to your oil, would it matter? There are really only 2 camps on the subject, believers that one additive is designed to work in all fluids and all possible applications, then those that don't believe it for a second. Choose your side and run with it.

 

[GA_Boater]

Got mine at Princess auto but Canadian tire also has it.

In another thread MMO was recommended to fix what turned out to be a failing ECM. It was your thread about a sluggish 5.0 Mercruiser.

 

[Jersey941]

In another thread MMO was recommended to fix what turned out to be a failing ECM. It was your thread about a sluggish 5.0 Mercruiser.

Last season I had a 1990 Yamaha 200. Ran good in May. June became sluggish. Followed a friends advice before tearing things apart and mixed one can of sea foam with one gal of gas. Ran for 5 min and let sit for 5 min. Repeated this 3 times to let the sea foam soak and clean the carbs. As predicted it spit sputtered and smoked for a bit then ran the best it ever did for the rest of the summer. Just my .02

 

[hugh g]

The only fuel additive I use is K-100. The stuff vaporizes moisture. I winterize all my small engines with it & add a bottle every now & then to my truck & wife's car. The rest is snake oil, including Sea Foam. I don't know if it will refresh 2 year old fuel so I hesitate to recommend it for your issue but it won't hurt to try. As far as MMO, I added it to the gas tank on my 3.0 a couple times & performance didn't change one bit one way or the other. So much for that idea. Never added it to the crankcase.

 

[demarko210]

Okay, hear me out first. Boat I have just purchased has 900L of two year old fuel that was stabilized. One solution is to syphon off all of the fuel into some sort of container and mix it with the gas in my vehicle. Other option is to throw some seafoam in the tanks, keep an eye on the fuel filters (just purchased two replacement) and replace them after running the tanks empty. Motors are 2008 VP 5.7L GI-J's. I don't think any serious damage can be done can it if I just run the fuel already in it? Maybe once half way, top off with fresh stuff.

I purchased this item from Amazon to pull the gas out of my tank. I also connected a fuel water separator to the line encase there was water in the fuel after I store the boat for the season. Its just a standard fuel pump and gas line. I let it pump for about 30 min. 15 minutes then i let it rest. then 15 minutes more.

 

[Nheels]

For anyone that was following along, engines run fine and I didn't add a thing. Changed the fuel filters though.

I'm now running into what I think may be fuel coming out of the exhaust, but still trying to figure that one out.. just seeing a rainbow skim in the water after stopping.. heavy fume smell as well, but no visible leaks.. another head scratcher!

 

[GA_Boater]

Sounds like either a misfire from weak or missing spark, possibly a motor running rich.

 

[Nheels]

Sounds like either a misfire from weak or missing spark, possibly a motor running rich.

Right, but they run fine.. at least from what I can tell. Which makes it even more of a mystery!

 

[demarko210]

For anyone that was following along, engines run fine and I didn't add a thing. Changed the fuel filters though.

I'm now running into what I think may be fuel coming out of the exhaust, but still trying to figure that one out.. just seeing a rainbow skim in the water after stopping.. heavy fume smell as well, but no visible leaks.. another head scratcher!

Rainbow could be coming from the lower unit may have a leak.

 

[Nheels]

Rainbow could be coming from the lower unit may have a leak.

I'll take a look at the levels. I know the trim pump is going and spurts when up high. (VP DPS-A)