Ethanol Gas - how to tell if bad

   / Ethanol Gas - how to tell if bad #1  

sld

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I have been worried about the 30 gallons of gas in my boat for the last 6-8 months. I was able to get a little bit drained off by pumping the primer bulb into a gas can. Didn't work too well so I used a mighty vac to see if it would help. Long story short, I wasn't able to get much gas out. The plan was to burn it in the mower if it looked okay.

The question is, how do you tell if it is bad by look or smell? I know the gas is coming from the very bottom of the boat's gas tank. It looks like gas, smells like gas, and even tastes like it (don't ask).

Is there an easy sure fire way to see if it has phase separated or if it's okay to use? I would hate to burn up a new 115 hp Mercury Optimax.

Thanks,

P.s. there has to be any easy way to siphon this stuff out without using a pump. I am open to suggestions. The mighty vac would fill the gas line and I would disconnect it in the bottom of a bucket (well below the boat tank). It would just run out and not keep going. There must be a check valve or something that keeps it from gravity flowing. I am hooking up to the fitting back by the engine where the primer bulb normally hooks up.
 
   / Ethanol Gas - how to tell if bad #2  
I doubt you can tell by looking at it. If it was me, I would burn it in an auto, like 5 gallons of the boat gas per auto tank. So that youre not burning at all at once. It seems like the big engines can tolerate older gas much better than small engines. Gummed up carburaters are a nightmare.
 
   / Ethanol Gas - how to tell if bad #3  
did you happen to use a fuel stabilizer formulated to ethanol???? If not, I think youre on the right track, pull some out and run it thru a lawn mower.... And its STILL not too late to add some fuel stabilizer. This happened with our jet skis.... and although they are 4 stroke and fuel injected.... I still drained almost 10 gallons out of each of them, they had 16-17 in each, then filled them with fresh fuel to basically "blend the old with the new" Also added stabilizer at that point... Put them in the water and rode the snot outa them all day..... never had any lasting effects...

I THINK you can successfully use all the old fuel, just may take some work to get it blended with some fresh stuff and stabilizer so that you dont foul a handfull of sparkplugs...

As for getting it out of the tank, a safe and easy way is to use an available piece of hose to access the tank, it should be long enough that the other end reaches lower than the fuel tank on the boat. Get it in there, get a 5 gallon can sitting by your hose end, take an air hose and put it beside the end of the hose and blow air the same direction as the end of the hose, allowing the air to pass across the end of the hose. It causes a low bressure vacuum in the hose, hold it there for several seconds and fuel will start flowing....
 
   / Ethanol Gas - how to tell if bad
  • Thread Starter
#4  
Actually, I use stabilizer in everything but the truck and cars (that use gasoline anyway).

Last fall, I put an extra dose of Stabil Marine in along with about 5 gallons of gas. This filled it to the point that the filler hose was full too. Shouldn't have been much dead air space and the boat lives in the garage year around.

What worries me is that I only had the boat out one time last year. I started a new job and worked pretty much every weekend. Some of the gas that's in there was marina gas from almost 2 years ago. At least the marina gas is more than likely non-ethanol.

The bottom line is I would feel much better if I could drain about 15 gallons out and refill with fresh gas. It just hasn't been as easy to drain as I had hoped. Maybe I should invest in a pump of some kind.

I just reread the last paragraph of your post. The filler cap is on the very front of the boat. I am not sure i can snake a hose all the way to the cockpit under the floor. That is why I was trying to pull from the fitting by the outboard engine.
 
   / Ethanol Gas - how to tell if bad #5  
If it's older than a couple months....prolly bad (or not as good as fresh).

Mixed gas for 2 cycle seems to last much longer, from my experience. Fortunately, I can still get ethanol-free gas.
 
   / Ethanol Gas - how to tell if bad #6  
The filler cap is on the very front of the boat. I am not sure i can snake a hose all the way to the cockpit under the floor. That is why I was trying to pull from the fitting by the outboard engine.

Did you open the filler cap when you were trying to drain the tank?
Or the system may need to be pressurized.

Sounds like the fuel might not be too bad with all the proper storage steps you took.
Dump in some 'heet' to absorb any water and run it.

Does it pump excess gas back to the tank when running?
You could disconnect the return and feed it into a gas can.

Or connect an in-line electric fuel pump to that squeeze-bulb line and pump away.

Goodluck
 
   / Ethanol Gas - how to tell if bad #7  
With stabilizer it should be good, but I see your point in not risking an expensive motor. My field truck (S-10) normally goes about 14 months between fill ups without any issues using stabilizer.
 
   / Ethanol Gas - how to tell if bad #8  
I go though this all the time being in the marine business. ONLY way to tell is get the gas out and put a sample in a glass jar and allow it to sit. You will see the separation.

Best money I have spent was 10 years ago I got 20' of fuel hose, a couple of 35 gallon drums, and a $25 40 gallon per hour electric fuel pump. Its a inline fuel pump for autos. Got it a Auto Zone I think. I put 15' feet of wire on it, some alligator clips, and a switch.

The pump is set up with 6' of hose on the in side and 14' on the output side. Simply remove fuel line from tank, install pump, put loose output hose in one of my barrels, turn on pump.

Chris
 
   / Ethanol Gas - how to tell if bad
  • Thread Starter
#9  
Thanks for the replies guys.

I did have the fuel cap off and it is a returnless system. There must be a check valve somewhere that helps keep a prime for the engine's fuel pump.

I will go ahead and get some type of pump so I can at least get 15 gallons out. I have a feeling that the gas is fine but there is a lot less risk in running it in the mowers than my outboard.

Also, I will put some in a jar and see what it looks like after a couple of days. I saw online some blue drops you can put in a sample. They either go straight to the bottom or blend in to see if the gas is good or bad. Probably wouldn't be a bad thing to have around. For the outboard the lack of octane would hurt just as much as having a bunch of water go thru it.

Our family vacation is right around the corner so I need to get this sorted out. I am so looking forward to 6 early mornings in a row of just me, my boat and a bunch of fishing poles in search of bass on Table Rock lake. There is nothing quite like sunrise when you are on the water. If southern Missouri gets any more rain this all may be a moot point.:mad:
 
 
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