Two year old fuel

[Nheels]

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.

 

[Commander_47]

If the fuel was stabilized, it should be ok.

If not, you can try mixing in 4 ozs of Marvel Mystery Oil for every 10 gallons of fuel. If I read your email right, that ship you have has about 900 liters?, or 238 gallons of fuel?

That would be about 7 gallons of MMO. This stuff is about $27.00 a gallon, so it will cost you about $189.00 if you dump in 7 gallons.

If the fuel was treated, you can use half that amount, or 4 gallon, maybe less.

The MMO will remove all moisture in the fuel and tank, and clean varnish from the lines and fuel system. The motors may smoke, belch and run like garbage for a few minutes, but should stabilize.

I use MMO all the time, and even run it when not stabilizing fuel. a few ozs just keeps everything nice and clean.

The biggest problem with old, bad gas is varnish. It hardens in the lines and blocks them, the carbs, and/or fuel injectors and such.

 

[Nheels]

If the fuel was stabilized, it should be ok.

If not, you can try mixing in 4 ozs of Marvel Mystery Oil for every 10 gallons of fuel. If I read your email right, that ship you have has about 900 liters?, or 238 gallons of fuel?

That would be about 7 gallons of MMO. This stuff is about $27.00 a gallon, so it will cost you about $189.00 if you dump in 7 gallons.

If the fuel was treated, you can use half that amount, or 4 gallon, maybe less.

The MMO will remove all moisture in the fuel and tank, and clean varnish from the lines and fuel system. The motors may smoke, belch and run like garbage for a few minutes, but should stabilize.

I use MMO all the time, and even run it when not stabilizing fuel. a few ozs just keeps everything nice and clean.

The biggest problem with old, bad gas is varnish. It hardens in the lines and blocks them, the carbs, and/or fuel injectors and such.

I'll have to look up that MMO stuff. Thanks.

 

[Captain Caveman]

Wow! 237 gallons of gas is a lot. Did you purchase a freighter??

Siphon some out into a gas can and give it the sniff test. If it smells like gas, then follow your plan to run it out. If it is iffy you can certainly add some fresh gas to dilute it.

 

[Nheels]

Wow! 237 gallons of gas is a lot. Did you purchase a freighter??

Siphon some out into a gas can and give it the sniff test. If it smells like gas, then follow your plan to run it out. If it is iffy you can certainly add some fresh gas to dilute it.

Yeah, the fuel jockeys are going to love when I pull in!

Would you suggest me adding Seafoam as well? I think the calculation is like 9L of the stuff.

 

[Scott Danforth]

Test your fuel. Its either barely ok, or it has turned to varnish

Seafoam does nothing

You cant fix bad fuel

 

[Captain Caveman]

I'm with Scott. If it is still fuel then run it. I don't use Seafoam for anything anymore.

If it smells like varnish, pump it all out and find a proper way of disposing of it that does not involve dumping it into the water or ground.

To be perfectly honest, I would certainly be concerned about fuel that wasn't stabilized. Of course, you don't know if the seller really stabilized it. However, I wouldn't have a problem running stabilized 2yr old fuel if it smelled fine.

 

[Nheels]

I'm with Scott. If it is still fuel then run it. I don't use Seafoam for anything anymore.

If it smells like varnish, pump it all out and find a proper way of disposing of it that does not involve dumping it into the water or ground.

To be perfectly honest, I would certainly be concerned about fuel that wasn't stabilized. Of course, you don't know if the seller really stabilized it. However, I wouldn't have a problem running stabilized 2yr old fuel if it smelled fine.

Thanks for the advice. Take care.

 

[Commander_47]

At Marina prices you have about $1,000 worth of gas in your freighter.

Sea Foam will not help with your gas.

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.

Let it soak overnight and then try starting them. While the engines are running you can drip MMO right into the intake and dissolve any varnish in the carbs.

It also works miracles with injectors.

I would think that tossing out the gas would be last resort.

 

[nola mike]

Not sure what MMO would do in this case (nothing to restore bad gas), same with seafoam. One thing I would for sure do is get a sample from the bottom of your tank and make sure you don't have water separated out (check/change your filters as well). If all checked out, and it smelled OK, I'd fill up the tank (how much is left?) to dilute the old stuff as much as possible.

 

[Nheels]

Not sure what MMO would do in this case (nothing to restore bad gas), same with seafoam. One thing I would for sure do is get a sample from the bottom of your tank and make sure you don't have water separated out (check/change your filters as well). If all checked out, and it smelled OK, I'd fill up the tank (how much is left?) to dilute the old stuff as much as possible.

Okay, I'll see if I can get a sample from the bottom of the tank. Thanks

 

[Texasmark]

If the fuel was stabilized, it should be ok.

If not, you can try mixing in 4 ozs of Marvel Mystery Oil for every 10 gallons of fuel. If I read your email right, that ship you have has about 900 liters?, or 238 gallons of fuel?

That would be about 7 gallons of MMO. This stuff is about $27.00 a gallon, so it will cost you about $189.00 if you dump in 7 gallons.

If the fuel was treated, you can use half that amount, or 4 gallon, maybe less.

The MMO will remove all moisture in the fuel and tank, and clean varnish from the lines and fuel system. The motors may smoke, belch and run like garbage for a few minutes, but should stabilize.

I use MMO all the time, and even run it when not stabilizing fuel. a few ozs just keeps everything nice and clean.

The biggest problem with old, bad gas is varnish. It hardens in the lines and blocks them, the carbs, and/or fuel injectors and such.

"The biggest problem with old, bad gas is varnish. It hardens in the lines and blocks them, the carbs, and/or fuel injectors and such."

You just answered a question I've had for a long time and just didn't pay attention to what I saw. On several occasions I came acroll tan material primarily in the feel line from the fuel tank to the engine. It fit the circumference of the inside of the fuel line and was crystalline in nature and came off in chips or irregular semi-circles. The last used boat I boat at 19 years of age was so bad it completely clogged the fuel filter and I'd bet you the owner didn't think to look for varnish chips in the fuel line and filter....he apparently thought his engine was on it's last leg....far from it. Didn't have a clue as to it's origin and now it dawns on me. Thanks.

 

[Commander_47]

Yes, it happens a lot in motorcycles. Folks put them up for the winter and then don't understand why it won't run in spring. The varnish has plugged everything.

But MMO will dissolve that varnish. Replacing the fuel filters is definitely a good idea. If it is carberetted, the tiny holes in the fuel jets can get clogged with varnish. Sometimes you have to use fine wire in the holes just to open them up enough to get the MMO to flow.

Dripping fuel into the intake can cause enough suction to open the holes up enough to get it to run then it is self cleaning.

 

[nola mike]

Yes, it happens a lot in motorcycles. Folks put them up for the winter and then don't understand why it won't run in spring. The varnish has plugged everything.

But MMO will dissolve that varnish. Replacing the fuel filters is definitely a good idea. If it is carberetted, the tiny holes in the fuel jets can get clogged with varnish. Sometimes you have to use fine wire in the holes just to open them up enough to get the MMO to flow.

Dripping fuel into the intake can cause enough suction to open the holes up enough to get it to run then it is self cleaning.

The MMO won't do anything to renew the gas. Even without varnish, it will still run like crap (if at all) if all the volatile HCs have evaporated.

 

[lrdchaos]

I would top it off with new gas and throw in some conditioner and see what happens. On my previous boat, granted it was a runabout with a 50gallon gas tank, it sat for a year and a half without being used due to a new baby. The fuel was stabilized prior to sitting though.
What I did was top off the tank and added a fuel conditioner in and ran the boat, topped off the fuel again, ran the boat, topped off again. Basically trying to mix new fuel with old fuel in it for the first few trips

 

[Nheels]

I would top it off with new gas and throw in some conditioner and see what happens. On my previous boat, granted it was a runabout with a 50gallon gas tank, it sat for a year and a half without being used due to a new baby. The fuel was stabilized prior to sitting though.
What I did was top off the tank and added a fuel conditioner in and ran the boat, topped off the fuel again, ran the boat, topped off again. Basically trying to mix new fuel with old fuel in it for the first few trips

Yeah, I think that's the best plan really given how much money I have in those tanks right now. I wonder if it is just best to use most of the bad fuel before topping it off with new stuff.. then I know it's good fuel moving forward after the first drain of tanks. Idk..

 

[lrdchaos]

I would use a little then replace, use then replace....but I don’t know how easy it is for you to get fuel.

 

[Commander_47]

I definitely understand not wanting to throw out about $1,000 worth of fuel at Marina prices. I tend to agree with irdchaos, Throw in couple pints of MMO and crank em up. If they run, then use carb cleaner and get the motors to stabilize.

If they run ok, then I would fill up the tanks and try to mix the old gas with new ASAP.

 

[Nheels]

I definitely understand not wanting to throw out about $1,000 worth of fuel at Marina prices. I tend to agree with irdchaos, Throw in couple pints of MMO and crank em up. If they run, then use carb cleaner and get the motors to stabilize.

If they run ok, then I would fill up the tanks and try to mix the old gas with new ASAP.

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

 

[Mcfltfyter]

If it runs ok, run it. Adding seafoam (emulsified water) isn't going to do anything helpful, and MMO is just... why? I will never understand why dumping random miracle additives in fuel gives people such comfort.