Question: Can I Use Nitro Fuel That's Been Stored for Several Months?
Nitro fuel becomes unusable when exposed to too much moisture and sunlight. How nitro fuel is stored is more important than how long it is stored.
Answer: Nitro fuel that has been properly stored is probably safe to use no matter how long it has been in storage. Ideally, if the nitro fuel is not to be used for several months it should be stored unopened in its original container in a cool, dark, dry place. After opening it is much easier for moisture to get to the fuel. It's also a good idea to dispose of unused nitro fuel from your field fueling bottles -- if it won't be used within a day or so -- rather than returning that fuel to the original container for longer term storage.
Keep the Moisture Out When Storing Nitro Fuel
The methanol in nitro fuel attracts moisture. Water in the fuel can hurt a glow engine. Don't leave nitro fuel cans open longer than it takes to re-fuel your RC. Limit exposure to the air, especially in humid areas. Keep containers tightly sealed and store them in a dry location. Keeping your nitro fuel under the kitchen sink, in the laundry room, or in a damp basement is not a good idea.
Keep the Sunlight Out When Storing Nitro Fuel
The nitromethane in nitro fuel breaks down with prolonged exposure to sunlight. Degraded nitromethane doesn't perform the way it should. Out in the field, keep your nitro fuel out of direct sunlight. If using a clear bottle for re-fueling, cover it when not in use. Store your tightly sealed containers of nitro fuel in the dark, especially out of direct sunlight.
