I got BAD fuel in my below deck tank.

txbandit44

Petty Officer 2nd Class
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May 11, 2008
Messages
182
I need to get this old fuel out of the boat with out removing the tank. Dont really want to siphon it with a garden hose. Is there a cheap way to do this? I though about an electric in line fuel pump but that like 45 bucks.
 

LippCJ7

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Re: I got BAD fuel in my below deck tank.

Carb or fuel injection? and how much gas? any idea?
 

scipper77

Commander
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Sep 30, 2008
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Re: I got BAD fuel in my below deck tank.

How much fuel are we talking about??

Ive heard of guys on here rigging up an the fuel pump to output into some sort of container, thus using the boats fuel pump to empty the tank.

Let me be clear about one thing. There is a significant risk of fire, explosion, loss of boat/home/life if you rig something up that isn't specifically designed to pump out fuel.

Please be careful and remember that the advice given here on this matter is from people with no liability or responsibility for your actions.
 

LippCJ7

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Re: I got BAD fuel in my below deck tank.

Also, how old is the fuel in the tank?
 

Home Cookin'

Fleet Admiral
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May 26, 2009
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Re: I got BAD fuel in my below deck tank.

need to know your rig to be specific

for an outboard: disconnect the fuel line from the first fitting (seperator, motor, whatever) and run it out the drain hole--you may need to add an extension. Get a syphon going, raise the tongue, hook up a primer ball, install a pump made for it--drain into jerry cans.

I was able to unhook at the motor and run the hose out. leaving the primer bulb hooked up, and use that to pump it out--when my hand got tired I was able to gently stand on it on the deck.

It's a lot safer to use the plumbed-in fuel line than to remove the sending unit and go in from the top--another option.

There are dozens of posts on how to clean the tank once you drain it, and what to do with the funky gas.
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
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12,932
Re: I got BAD fuel in my below deck tank.

i used a pony pump.

took 60 gallons out.

just be careful.......and dont use the gas in any small engines
 

txbandit44

Petty Officer 2nd Class
Joined
May 11, 2008
Messages
182
Re: I got BAD fuel in my below deck tank.

Whats a pony pump?

Its in an old ranger bass boat with an outboard.

Gas is around a 1 yr old

think its about 9-10 gallons.
 

Philster

Captain
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Sep 15, 2009
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3,342
Re: I got BAD fuel in my below deck tank.

Hmmm... how much can the talk hold?

I might be inclined to top it off with premium, add some treatment that treats water, checks my water-separating filter and fire her up.

What engine?

Also, have an extra filter on hand.

.
 

BRICH1260

Lieutenant
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Jul 6, 2011
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1,342
Re: I got BAD fuel in my below deck tank.

A year is not all that long. What makes you think that it has gone bad? Do you have more room in the tank that you could add more premium fuel and some stabilizer and just run it through the engine.
 

Silvertip

Supreme Mariner
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Sep 22, 2003
Messages
28,758
Re: I got BAD fuel in my below deck tank.

Adding premium fuel is no better than regular. Add some Sea Foam, top it off with regular and go boating. One year old fuel is not bad unless it has a great deal of water in the tank with it. If there is no water, you don't have a problem.
 

tpenfield

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17,624
Re: I got BAD fuel in my below deck tank.

I need to get this old fuel out of the boat with out removing the tank. Dont really want to siphon it with a garden hose. Is there a cheap way to do this? I though about an electric in line fuel pump but that like 45 bucks.

On my boat's built-in tank . . . . I used a hand pump designed for fuel (about $15) along with some tubing and connected it to the tank's fuel line. It took a long time to pump out. ( about 25 gallons as I recall )

A better choice is if you have a slope or small hill, you can set up a siphon and drain it in a more relaxed fashion.
 

PrinceValium

Chief Petty Officer
Joined
Jun 2, 2010
Messages
421
Re: I got BAD fuel in my below deck tank.

Adding premium fuel is no better than regular. Add some Sea Foam, top it off with regular and go boating. One year old fuel is not bad unless it has a great deal of water in the tank with it. If there is no water, you don't have a problem.

I agree with you. SeaFoam would help a lot.
 

Philster

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Re: I got BAD fuel in my below deck tank.

I agree that premium isn't a must, but I suggested what I would do, because without knowing the engine, I'd rather have a little more octane just in case the fuel in the tank lost some. Chances are it won't matter; filling the tank and treating the fuel is probably all that needs to be done here.

Since the tank wasn't full, all indications are that some water might be present, so treat it and have a filter up to the task. Draining doesn't seem necessary.
 
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LippCJ7

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Re: I got BAD fuel in my below deck tank.

I always put the good stuff in(premium) the first full tank of the season as Philster recommends, its personal preference but its what I do, 1 yr old gas that has been stabilized will be fine, and you should have another fuel filter on your boat anyway, Don't sweat it you will be fine, have fun I envy you that your getting ready for boating I'm a month or so out yet!!
 

Home Cookin'

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Re: I got BAD fuel in my below deck tank.

first we need to hear back from OP about why the gas is "bad."

If it is "bad" such as phase seperation or kerosene smell, adding sea foam, stabil, or fresh gas won't fix it.

if there is water in the tank, additives won't take out the water. . For one thing, the water is at the bottom, first thing the tube picks up, so no matter if there's 5 or 50 gallons on top of an inch of water, there is still an inch of water. And salt water is worse. And I wouldn't rely on a water seperator to handle it, either, if I knew it was a lot; they are designed to keep out some water but not to clean bad gas.

Adding fresh gas to bad gas won't make bad gas fresh. It will, however, dilute the "badness" to a point where your motor might not notice. So if I had really bad gas (my wife says i do) then I would remove it. if it was marginally bad, or just old, no kerosene smell, I might dilute it.

one year old gas in Texas can be bad due to heat, humidity and temperature fluctuations, but not necessarily.
 

txbandit44

Petty Officer 2nd Class
Joined
May 11, 2008
Messages
182
Re: I got BAD fuel in my below deck tank.

Its a 84 115hp johnson. I say bad because 1 its a yr old and fuel starts to turn after 3-4 months 2. I dont remember for sure if I added stabilizer before the winter. Its a 18 or 20 gallon tank. Im working on my other motor right know. The PO ran old gas in it and caused detonation in #1. Which sent chunks of piston banging around in 2 and 3. SO kinda freaked out about bad fuel now in my only serviceable boat at the moment.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: I got BAD fuel in my below deck tank.

The gas is a year old. It hasn't phase separated. Water is a problem. The fuel is not. Unless of course it is not really one year old but maybe 2 or 3.
 

Philster

Captain
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Sep 15, 2009
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Re: I got BAD fuel in my below deck tank.

Detonation from really old gas that was low in octane... we could go 'round and 'round... and even though I'd fill 'er up with premium and treat with something that also treats water and have my filter(s) good to go, if ya got that previous owner issue on your mind, to sleep at night... well, you just might have to drain 'er.

And ol' 2-stroke Johnny-Rude = just run it, baby!... but you have that issue on your mind. Rats.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Re: I got BAD fuel in my below deck tank.

phase separation starts within weeks on e10 if it sits. it takes the constant agitation of a return fuel line to prevent it.

If it still smells like gas, burn it up. if it doesnt, get a fuel siphon pump and change it.
 
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