radcon56

I bought some omega 15% nitro with a castor/synthetic blend and half a gallon has been sitting around for about 3 months now.How long will glow fuel last? I have kept it in a cool dark closet for storage.

freebird25

as long as the lid was on tight...3 months won't be long enough to make a difference

G8S

My LHS owner told me the other day that he's used 12 year old glow fuel before with no problems. It had never been opened until he used it. He added that once you've opened a jug, it won't keep as long as an unopened one (he didn't say how long, though).

Jim Thomerson

I have a half gallon of Red Max 5% fuel that is @ 25 years old. It ran OK the time or two I used it on the bench, but I'm not taking it out to the flying field.

Jim

Phlip

Somebody (LHS Owner?) told me that the nitro goes away, with time, right through the plastic jug. He didn't say how long he thought it takes.

For sport flying, where high nitro content isn't important, I'd use fuel that's up to 5 years old, as long as it has been capped tightly.

I heard somewhere that the biggest problem with fuel going bad is that it absorbs moisture. But then again, I read somewhere recently (RCU? FM?) where a guy added water to his fuel and increased the performance of his engine! Some speculation that it may have the effect similar to water injection used in some WWII warbirds.

My fuel tend to last up to a year routinely, and I've never had any fuel related problems... knock, knock.

Phil

FHHuber

Stored properly... glow fuel is good for YEARS.

Some old formulations used to have an aditive that could cause a crystalization on the threads of the can cap. these crystals were closely related to... Nitroglycerine. Took several years to form a dangerous amount of them but if you did... you could have quite a bang when you opened the can. (if you have a 20 year old can... call the fire dept and get it disposed of.)

Modern Glow fuel does NOT use that additive. (I think it went out of use in the 1970's... or early 80's)

I have heard of 10 year old fuel being used with no problem.

3DFanatic

My Feedback: (5)

Saweeeeeeeet! I want one of those cans!

3D Flyer

My Feedback: (37)

I had a 15 year old metal can of unopened K&B fuel that
ran just fine at the field this summer. If its unopened I would not worry to
much.

Gringo Flyer

My Feedback: (18)

My wife is a chemist and she says that it is impossible that nitro could pass through a plastic container like the LHS said. Laws and not to mention common sense would not allow a manufacturer to put a volatile and hazardous substance in a container that it could leak out of. If it could pass through the plastic it would be put in metal or glass containers. It's great when 50,000 dollars worth of tuition helps to answer a forum question!!!

CafeenMan

I've heard that fuel gets better with age. I don't know how the person who said that came to that conclusion, but I've used fuel that is many years old with not problems. If you have a jug in your field box that uses ends that simply plug into fittings, it will stay good for a long time, but if you know you won't be flying for months, it might be best to put a sealed lid on it.

FHHuber

As you get older... you like using the fuel more.

Live Wire

Alcohol get better with age. Look at champain We had some fuel in the old day that the caster would seperate and get solid and the additive was to keep the fuel from foaming . The only thing that realley bothers fuel is evaperation of combustable materials, and all you have left is oil.

Phlip

Here, here!

I figured that was kind of crazy... good to hear it from a learned person though.

A couple other things I remember from the article about adding water to glow fuel are that:

1. It was a C/L engine used, so no throttle testing was done.

2. The needle valve had to be opened approximately one more turn (probably in proportion to the amount of water in the fuel). And... hence...

3. The fuel consumption rose proportionally as well. But, about 1K more RPM on the same prop.

Azcat59

I left modeling (U/Control) in late 1963. Had several gallons of fuel, different brands, all in the metal cans of the day. Got into RC in early 1977, and one can, only about 1/4 full, was kind of "curdled", but the rest were fine, and ran fine. All were 5% nitro I think.

Clair
AMA 15654

linclogs

I use old fuel (as much as 3 or 4 years old) whether it has been opened or not. As long as the oil in it has not coagulated into tiny globs and it is not clouded or changed to a funny color, it's always worked fine. If it has deteriorated, I generally only use it for cleaning engines.

FHHuber

Generally, water in glow fuel will give so much trouble you won't get the engine to run. it cools the combustion chamer, and can quench the glow plug (cool it to the point the ignition cycle doesn't happen the next engine revolution.)

I forget hte name of the crystals, but its one of the silicone based gels that expands as it absorbs water. (used as a "molecular Seive" ) Fuel that doesn't work well can have these crystals added... about 2 houtrs later... the crystals will be larger and the fuel will work well again. The crystals won't absorb the oil or alchohol because the molecules are larger then the water molecules the crystals are made to grab. (they will grab water molecules off of alchohol and potentially can turn Ethyl alchohol into ether.)

3DFanatic

My Feedback: (5)

Yup yup, no way the nitro's going to penetrate that plastic.

mattsimonton

I have heard moisture will make it go bad and light will break down the nitro.
My mom's ex said all of that when I saw a guy blending his fuel. Eric said that the fuel will go bad with light. But about a month later we went flying and a hotter than heck day "a lot of light" he was using 16% in a clear jug so I hear one thing and see another.

But I use the cheap gallon stuff and it works great and there is a lot of light in Oklahoma.
But I hope some one can clear up your question
Matt

Azcat59

The methanol is hydroscopic, i.e. it attracts moisture. If the bottle "sweats" you may see drops of water in the plastic jug, and you are apt to have problems with engine consistency in running it. This happens once in awhile even here in the desert. And I understand that light does deteriorate nitro, but I think that is over a period of time, not just a few hours out at the flying field. I do keep my fuel inside the cardboard carton until I am ready to open a new bottle.

Most of the time though, our engines run pretty well with no special handling of the fuel.

Clair
AMA 15654