Old gas. How old is too old?

KrisM

Lunatic Member
Hey AK auto people. I'm not too up with cars and such, but as I do every year at this time I get ready to put away the lawnmower and have extra gas leftover.
I know from experience that if I store this gas over the winter, and put it into the lawnmower it's past it's best and the mower won't start.
What ends up happening is I forget about it until spring, and then have to take it to an ecostation.
I figured I'd ask this year if I'd smart to pour into my vehicle's tank.

Am I good to go, or should I dispose of it?
The gas was purchased in May, and stored in my garage(0c to 30c temps), and would be going into an old Jeep Cherokee.
I forget the octane, but I think it's premium.

Thanks!
 
I figured I'd ask this year if I'd smart to pour into my vehicle's tank.

Am I good to go, or should I dispose of it?
The gas was purchased in May, and stored in my garage(0c to 30c temps), and would be going into an old Jeep Cherokee.
I forget the octane, but I think it's premium.

Thanks!
Every fall I dump the summer's leftover gas into whatever vehicle is low (unless said vehicle requires premium). This practice has never caused so much as a hiccup yet. BTW, there's no need to pay the big bucks to put premium in your mower. Use regular. Trust me, it'll never know the difference.
 
I use Berryman's B 12 liquid as a gas stabilizer in my motor cycle and boat,
about $3.00 at Walmart.
 
I use Sta-bil and no alcohol premium recreational fuel in all our boats, mowers, pressure washers, ATV’s, snowmobiles, backpack blowers, and chainsaws. Yes, I’ve got a lot of spark plugs to deal with. Never had any issues with storing over the winter but always cycle new fuel into everything during the Summer.
 
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I have vehicles that sit for years.
1-2-3 roughly.
They all start and run fine. I fill them soon after starting, day or three.

The really old gas is like 5-6-7 years.
It burns, but stinks.


Most problems I see in small engines is the rubber parts rotting out.
Primer bulbs, gas lines.
I never empty my mowers.
First start in the spring is mostly getting the gas primed and not flooding it.
A little luck with the pricing and cranking and its off to the races.


I snag free stuff off the street.
Probably not started in years.
Fresh gas, prime it, crank it, check for spark, crank it and 99% fire off and run.
The other 1% have some serious issue so they get recycled.

I bought a jug of stabl years ago.
Still haven't used it.
It should be good, right?
 
I bought a jug of stabl years ago.
Still haven't used it.
It should be good, right?

Do you mean STA-BIL Fuel Stabilizer? As far as I know it will last indefinitely if sealed. Probably still a long time if unsealed but tightly capped. Or did you mean some other product?

(Stabl is an engineering program for determining maximum angle of repose and how to improve it.)
 
I use Sta-Bil in any fuel that I store for long periods of time--months to a year. For vehicles or equipment that I store over the winter, I try to run them pretty low on fuel, so when I add fresh fuel in the spring, there is very little old fuel, and it gets heavily diluted with the fresh fuel. When I owned "classic" cars and motorcycles that would sit over the winter, I would pull the plugs and put a little bit of 2-cycle oil in each cylinder to keep the rings wet, and it is meant to be burnt anyways--they'd smoke a little on first start, but goes away rapidly. I wouldn't do that with any new vehicle with O2 sensors or cat crackers due to fouling issues. I still do that with my small engine devices and my heavy equipment that sits over the winter--just call me OCD. MMO (Marvel Mystery Oil) is supposed to be good for this as well, but I have never tried it, since I always have quarts or gallons of 2-cycle oil on-hand.

I always have multiple 5-gal containers of gas in the shop for lawn equipment, and if it doesn't get used by the end of the season, I dump it into my cars to get rid of it and buy fresh to replace it for the winter--again, the OCD in me. Gas is delequesent/hygroscopic,, so it does absorb water over time, so I don't like to store it too long.
 
I try to run my lawnmower out of gas, (engine dies). If I don't, and have a little left, I leave it. The next Spring, (first use), I make sure the fresh gas has a good mixture of Sea Foam added.
 
My Honda mower will run fine each spring, on gas left over from the last fall.

Of course, I keep the mower stored in a closed cabinet all winter. No exposure to the elements. Probably doesn't suck up much moisture that way...

Regards,
Gordon.
 
Thanks for all the great info, guys!
I’ve got about 3/4 of a tank in the Jeep right now, so I think I’ll top it up this weekend.

Those that have lawnmowers that start in the spring with old gas, do you live where it doesn’t get too cold?
Around here we can go from almost 30c in September to -25c in November. -30c(or worse) is not uncommon during our winters.
 
When my mother moved last spring, we found a plastic gas can in the garage, for a mower that had sat unused for two and a half years; after my brother moved out, she hired out for the mowing. I took them home, and used the mower and old gas all summer long, with the Toro starting on first or second pull all summer long.
 
I never store gas in power tools over the winter--the varnish from the gas can gum up carburetor jets. Don't ask how I know this. It might not plug jets completely, but it can plug them enough that it will not run properly.

Even if you keep gas in the tank over the winter (with stabilizer), at least shut the fuel valve off and run that gas out of there. It's not worth it to me to spend hours screwing with a plugged carb, or spending $60+ for a genuine new one (not those no-name chinese knockoffs).

The worst I've ever seen? My dad had a snowblower at his house, and it took me maybe half an hour with electric start to finally barely get it running, since he had never drained the old gas out of it. The carburetor was gummed up from it and even with fresh gas, it barely ran. I handed it down to someone in the family and they had to get the carb cleaned and rebuilt. It would just about run if it was kept on full choke.
 
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