Advice on fuel in tanks - Use or remove
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Advice on fuel in tanks - Use or remove
I have not used our boat much in the last 2 years, used once last fall in the last two years. It ran fine then but no gas was added. It's an 80 gallon tank with probably 40 gallons in it. Plan to use it more this year but am worried about the condition of the gas. It was stabilized two years ago but not since. Considering removing gas and refilling. The motor is a 2002 Mercury 200hp Carbed. I am in SW Ga, though Tallahssee is in range, does anyone know of a company that can pump out and clean tank?
- Dubble Trubble
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Re: Advice on fuel in tanks - Use or remove
I keep my boat inside a building, and have never had any problem using last years gas. Of course, I only use non-ethanol gas.
If it was ethanol gas, I would at least at some Sta-bil to it now and burn it out in the spring.
Also, if the boat was kept outdoors, you will have even more chance of moisture in the tank.
Carbs will be a little more forgiving than Fuel injection will.
Dubble
If it was ethanol gas, I would at least at some Sta-bil to it now and burn it out in the spring.
Also, if the boat was kept outdoors, you will have even more chance of moisture in the tank.
Carbs will be a little more forgiving than Fuel injection will.
Dubble

The more I know about something, the more I know that I did not know as much as I thought I knew that I knew.
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Re: Advice on fuel in tanks - Use or remove
After 2 years I would recommend removing it. If you remove the cap and it smells at all like varnish instead of gas, it is bad. You don't mention whether it is non-ethanol gas or not. If it has any ethanol, you can bet that it is bad. Harbor Freight sells a small pump that you could probably use to pump it out of the tank. If you remove the motor end of the fuel line and add some hose to it, you may be able to siphon it out by getting it started with the primer ball. You will have to have the end of the hose lower than the tank.
I would also replace any water separators or filters while you are at it. I am afraid that if you don't you will just have more problems.
I would also replace any water separators or filters while you are at it. I am afraid that if you don't you will just have more problems.
- Gulf Coast
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Re: Advice on fuel in tanks - Use or remove
I would take it out...burn a little in a car every now and then.
- fishinfool
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Re: Advice on fuel in tanks - Use or remove
A couple of bottles of this
That should suffice to remove any moisture, condition the fuel, and raise the octane to a suitable level. I would also add a pint or two of Marvel Mystery oil to the 80 gallon mixture. Replacing the filters before and after burning that 80 gallons would be a very good idea as well.
and fill the tank with premium fuel.
That should suffice to remove any moisture, condition the fuel, and raise the octane to a suitable level. I would also add a pint or two of Marvel Mystery oil to the 80 gallon mixture. Replacing the filters before and after burning that 80 gallons would be a very good idea as well.
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Re: Advice on fuel in tanks - Use or remove
Remove it. Be very very careful. I bought a boat last year with gas at least a year old in it. Didn't run well at all. Siphoned all the gas out, replaced filters. Filled with non-ethanol & did seafoam treatment. Runs great!!
I use the gas I took out in the lawn mover etc.
But be careful! A little spill can cause big problems.
I use the gas I took out in the lawn mover etc.
But be careful! A little spill can cause big problems.
Re: Advice on fuel in tanks - Use or remove
Or dump it on a Fireant bed!Gulf Coast wrote:I would take it out...burn a little in a car every now and then.
SS-342
198DLV CS 115HP
13' Gheenoe 6HP
198DLV CS 115HP
13' Gheenoe 6HP
Re: Advice on fuel in tanks - Use or remove
Thanks for the suggestions, I think I will remove it. It is non-ethanol gas, but it's probably worth it to be safe. I always use premium non-ethanol gas and will add some fuel cleaner to the new gas. Hopefully I will get to use it more and not have it sit so long.
Re: Advice on fuel in tanks - Use or remove
I helped a friend pull 40gal out of a boat at new years. We just disconnected the line from the tank to the water separator and connected a fuel pump we had laying around. I think it cost $20. A little extra line and we used the battery in the boat to run it. Didn't take but 30 min for everything. Now its topped off with non ethanol. Good luck!