jill210

I haven't got to do hardly any flying in the last couple of years. Spent all my flying time working on the house. House is done and now I'm flying again. Question is how long does opened fuel stay good? I think mine is old. I had some open when I was flying last (year and a half ago) and I notice when I use it in my Saito's now, they miss and cough a little. Could that be the problem? I wonder if some of the alcohol has evaporated and also has drawn moisture. Fuel is Omega 15%. I also had some two cycle Champion 10% fuel that was open and I know it was bad. OS motors would smoke like crazy and just die. Threw it away. Went to new fuel and they ran fine. Please help.

JIM

bbbair

The fuel will last for YEARS, IF it is sealed properly and stored in a cool place.

Big on the "Sealed" part.

You are correct about the loss of nitro and absorbtion of moisture - but that only happens if the container has been left open.

If you are truely worried - trash the old stuff and buy fresh - no problems!

jetmech05

see if you can borrow some fresh from a fellow flier. use it to troubleshoot the coughing sputter prob.
But I think if I was in doubt I'd just get fresh

BillyGoat

The chances that bad fuel is causing your problems are pretty good. But not definite!

When your getting that new jug of fuel get a new glow plug too. Also wouldn’t hurt to examine your fuel supply system (tank and lines).

jill210

I have already bought new fuel. Just haven't tried it yet. Next time up I will. Just was wondering about how long you can keep it. It wouldn't have been completely sealed as the filler lines were in the cap. Thanks guys.

flyingfever

I laid off the sticks for nearly three years while an, "open" gallon of fuel sat in my garage. It was, "open" in the sense that the seal had been broken, and I had assembled it onto my field box fueling system. I'm back on the sticks now, and have been blending a bit of the old fuel into a new gallon a little at a time with no adverse affects so far. I thought about trashing the old stuff, but I'd rather burn it than send it to the landfill.

Fever

BillyGoat

Fever, it’s good that you’re able to burn some of your old fuel with new. I would probably do the same thing myself. However I would mix it in the tank just incase the old fuel does have an undesirable affect, then the new gallon isn't trash too.

flyingfever

Actually, I burned a fresh gallon down to 1/4, then poured some of the old fuel in to make a 1/2 gallon, 50/50 mix of old and new. That has been working well so far. No engine malfunctions. I may wait until I burn 1/2 of another new gallon, then pour in 1/2 of the old stuff to use it up. This way I won't go above 50% old fuel in the mixture.

Fever