Gasoline Shelf Life
- Thread starter daverami
- Start date
mountainpete
Spamicus Eliminatus
I think the answer has changed over time. The article says a couple of months to, with stabilizer added, a year or so.
We used to leave outboard motor gas sit all winter, and use the balance next season without issues. Never really thought about it back in the 50's and 60's.
In 1991, I parked my '79 Mustang in the back yard in Alaska, pulled the battery, and covered it with a tarp. It had a half tank of gas on board. In 2002, I pulled it out of mothballs, put in a battery, and it fired right up and ran fine on what was then 11 or 12 year old gas. I sold it 6 months later with the same gas in the tank, still running great.
On the other hand, I understand folks in Phoenix can't leave gas sit around the garage for more than a month or two if they want the lawn mower to start, so I guess it varies with climate, and with the times.
We used to leave outboard motor gas sit all winter, and use the balance next season without issues. Never really thought about it back in the 50's and 60's.
In 1991, I parked my '79 Mustang in the back yard in Alaska, pulled the battery, and covered it with a tarp. It had a half tank of gas on board. In 2002, I pulled it out of mothballs, put in a battery, and it fired right up and ran fine on what was then 11 or 12 year old gas. I sold it 6 months later with the same gas in the tank, still running great.
On the other hand, I understand folks in Phoenix can't leave gas sit around the garage for more than a month or two if they want the lawn mower to start, so I guess it varies with climate, and with the times.
sandalscout
Adventurer
I've also had gas sit just fine for years.... my 1986 Vanagon sat from 1992-92ish to 2003 with the same gas, and I used that whole tank with no problem.
Superu
Explorer
Sta-bil
I add sta-bil to the gas in my lawn mower, snowblower, generator and lawn tractor every season as they go into storage as the seasons change. Also add it to my Scepter cans to keep the spare gas fresh.
Never had a problem with stale gas. Even after it sat for over a year in the generator tank.
I add sta-bil to the gas in my lawn mower, snowblower, generator and lawn tractor every season as they go into storage as the seasons change. Also add it to my Scepter cans to keep the spare gas fresh.
Never had a problem with stale gas. Even after it sat for over a year in the generator tank.
motomech
Adventurer
I work on small engines for a living(Lawnmowers weed eaters and such) and you wouldn't believe how many people come in saying it wont start and its just bad gas.
I tell them that a lawn mower has only one cylinder and a V8 has multiple cylinders....so if a V8 has bad gas it has other cylinders to help it along it may seem like its running in tip top shape but its not...now if a mower has bad gas you will know it right away since it doesn't have other cylinders to help it along.
My vote is 6 months or if you add a stabilizer up to 1 year
I tell them that a lawn mower has only one cylinder and a V8 has multiple cylinders....so if a V8 has bad gas it has other cylinders to help it along it may seem like its running in tip top shape but its not...now if a mower has bad gas you will know it right away since it doesn't have other cylinders to help it along.
My vote is 6 months or if you add a stabilizer up to 1 year
ntsqd
Heretic Car Camper
Diesel fuel is hygroscopic, it will absorb moisture out of the air. Once that happens you'll start a bacteria farm and the fuel is suspect. Used to be that diesel was much longer lived that gasoline due to the lack of light ends. With the newer formulations I don't know that this is the case any more.
Moody
Needs to get out more
Great question. I have wondered the same thing. I cycle through my 'extra' 15 gallons every 6 months. I guess I am okay.
FWIW, I worked on an early 80's (I think) Honda 90 with my father in law that the gas had gone bad, and gummed up the carb and the tank was a stinky mess. Once it was all cleaned out, it ran fine, and still does. That fuel was in there for 15+ years though....
FWIW, I worked on an early 80's (I think) Honda 90 with my father in law that the gas had gone bad, and gummed up the carb and the tank was a stinky mess. Once it was all cleaned out, it ran fine, and still does. That fuel was in there for 15+ years though....
Robert Bills
Explorer
Someone must have been reading my mind.
My Jeep CJ-7 hadn't been used much during the past year, had nearly a full tank of gas and I never got around to buying any StaBil. I was concerned that I might destroy my motor with stale gas, and resolved to drain the tank and refill it with fresh gas before I ran it again.
Unfortunately, my daily driver Grand Cherokee developed a front wheel bearing issue just after my local jeep shop closed for the Labor Day weekend and I had no choice but to press my CJ into service without addressing the "stale fuel" issue. Fortunately, nothing bad happened when it started. I drove to the closest name brand gas station, topped off the tank with 2 1/2 gal. of fresh gas, and burned 7-8 gal. (of my 19 gal. capacity) during the weekend before getting my daily driver repaired. Seemed to run fine.
So my quandary is whether I can simply top off the tank again (which will create a mix of 60% fresh gas to 40% old gas) and get on with life, or whether there is a true risk of engine damage if I don't dispose of the old gas.
Your thoughts?
My Jeep CJ-7 hadn't been used much during the past year, had nearly a full tank of gas and I never got around to buying any StaBil. I was concerned that I might destroy my motor with stale gas, and resolved to drain the tank and refill it with fresh gas before I ran it again.
Unfortunately, my daily driver Grand Cherokee developed a front wheel bearing issue just after my local jeep shop closed for the Labor Day weekend and I had no choice but to press my CJ into service without addressing the "stale fuel" issue. Fortunately, nothing bad happened when it started. I drove to the closest name brand gas station, topped off the tank with 2 1/2 gal. of fresh gas, and burned 7-8 gal. (of my 19 gal. capacity) during the weekend before getting my daily driver repaired. Seemed to run fine.
So my quandary is whether I can simply top off the tank again (which will create a mix of 60% fresh gas to 40% old gas) and get on with life, or whether there is a true risk of engine damage if I don't dispose of the old gas.
Your thoughts?
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