How to tell if the gas is bad?

Fishermark

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This boat I just bought has been sitting up for about a year. It has a 118 gallon fuel tank. I had assumed it would be about empty, and was planning on simply removing the old gas and putting in fresh. Well, lo and behold, I removed the sender and it is full to the brim! About a hundred gallons of gasoline. Is there a way to tell for sure if the gasoline is good? Is there an additive that can be added? Should I remove it "just in case?" If so, how do I go about it? Is this something marinas often do? :confused:
 

Bondo

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Re: How to tell if the gas is bad?

"Is there a way to tell for sure if the gasoline is good?" <br /><br />SMELL It...... Good Gas Smells like Gas... Bad Gas StinkS....<br /><br />I'd Dump in a Gallon of Marvels Mystery Oil,+ Go for a Boat Ride.....<br />The Rate of time for gas to Go Bad, is in Direct Proportion to the Volume of gas........<br />In other words... The Cup of gas in your Carb will go bad in months...... !00 Gallons takes quite abit Longer.....
 

Fishermark

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Re: How to tell if the gas is bad?

I'd Dump in a Gallon of Marvels Mystery Oil,+ Go for a Boat Ride..... <br /><br />This is a brand new 2003 5.7 liter Mercrusier engine I am installing. Would you take the chance with a new engine? By the way, it smells fine.
 

Seaboo2

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Re: How to tell if the gas is bad?

Gas smells either like gas (good) or "sweet" (bad). Personally with a new engine (if I wasn't SURE the gas was good) I'd remove it and not take the chance.<br /><br /> Shelf life on gas is about 3 months but I've seen it store much longer. If the gas was stablized it will store for a year +.<br /><br /> I'd remove it with a transfer pump (cheep ones can be bought for about 10-30 bucks).<br /><br /> You could go as far as to dump a gallon into your lawnmower and see if it runs to kinda determine if it is good (but considering it is nearing season end and you are installing a new engine it might just be getting stored for a couple months longer).
 

Fishermark

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Re: How to tell if the gas is bad?

I don't worry too much about season here in south Florida... but I might try the lawnmower route.
 

Bondo

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Re: How to tell if the gas is bad?

I'd Dump in a Gallon of Marvels Mystery Oil,+ Go for a Boat Ride..... <br /><br />This is a brand new 2003 5.7 liter Mercrusier engine I am installing. Would you take the chance with a new engine? By the way, it smells fine. <br />
Yes.... If it Smells like Gas.... It Is....<br /><br />100 gallons in the Lawn Mower ???? That's about 10 years Worth.....
 

loadnet

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Re: How to tell if the gas is bad?

I agree... with the smell factor.<br /><br />If the gas smells good like all gas 'should smell' just throw some conditioner in it, and put that worry to bed.<br /><br />If you have an auxilary fuel filter off away from the engine, just change it and fill it full of fresh fuel.<br /><br />If you want to toss some in your lawn mower that's a good idea to test it.<br /><br />You can also pour a pint of it into a clean coffee can to see if there's any liquid separation. White color vs dark color - darker color being the gas, white color being the water.<br /><br />If you don't see any white liquid near the bottom of the container or very very little white - you'll be fine.<br /><br />go for it.
 

crazy charlie

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Re: How to tell if the gas is bad?

Hey fishermark just taste it!!!!!I hear it is just like bad beer,you can taste if it is bad right away!!!Try a swig.......
 

Fishermark

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Re: How to tell if the gas is bad?

I think I see why your name is Crazy Charlie! :p
 

zzzzz

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Re: How to tell if the gas is bad?

Fishermark-if you decide to remove fuel there is a place in Fort Myers Beach we use...they take old fuel and clean your tank...Florida Sludge Suckers at (239)872-2356 :cool:
 

Fishermark

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Re: How to tell if the gas is bad?

Thanks zzzzz.<br />I notice from your homepage that you work at Gulf Coast Marina in El Jobean. That's not too far from me. :cool:
 

LubeDude

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Re: How to tell if the gas is bad?

If you will seach the forum you will find a lot of us have dumped sour fuel into our cars and trucks and they dont mind at all! Inboard Boat engine, car engine, Very similar! As long as you have a good water sediment fiter on your boat you are not going to have any problems! As you say the gas smells like gas so you are going to be fine!! Now an outboard I might consider changing it as they tend to be a little more picky!!!!<br /><br />LubeDude
 

ISkiH2O

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Re: How to tell if the gas is bad?

I'd run it on new fuel first just to be sure the engine runs fine. Maybe rig up an auxillary tank. At least some of the stabilizers claim to help old fuel. Adding it would be cheap. You could also mix it with fresh gas, run it wherever. I would think it's better to have the full tank than one that was almost empty.
 

Fishermark

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Re: How to tell if the gas is bad?

In regards to the auxillary tank, that's exactly what I had in mind. I still have a couple plastic six gallon tanks I used for the outboard on my old boat. It should work fine to make sure the the new engine is up and running good before "experimenting" :eek: with the old stuff. I will probably pump about half out into a drum - add some fresh, then when I use that up, put the other half back into the tank with some more fresh fuel. I will add some stabilizer just for good measure.
 
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