Last Year's Gas?!!


Member II
ok, my first alaskan winter with ericson 25-
winterized the merc. 15 hp outboard- tarped
the boat- did most things right... but totally
forgot about two, 5-gallon jerry cans (newer
plastic containers) of GAS! it's been 8 months
of temps ranging from 30 F to minus-10-

do i dump this gas, or should it be ok to use
on this older, 2-stroke outboard??

brian smith
s/v sparkle plenty
homer, ak


Sustaining Member
I'd pour it in your truck instead. It's going to give you trouble in the outboard and it'll take you a while to use up. If you pour it in your truck/car when it's 3/4 full of new gas, you won't even notice it.

In the future, I'd just pour the stuff in your car's tank in the fall, or if you want to store it, add some "Sta-Bil" fuel stabilizer.


Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
If I had a newer vehicle with injection, I would not put any oil/gas premix into the vehicle tank. Sounds like potential trouble...
But I am not a mechanic.


Sustaining Member
I've not had a problem in my injected truck doing this from time to time with old chainsaw mixed gas.

Probably not good to fill an empty tank this way, but as long as you're dilluting it 4 to 1 with a full tank of normal gas, I wouldn't personally worry about it. On the other hand, I don't drive a Bentley or anything. :)


Member III
When faced with similiar challenges, I like to take consider the issue over a few smokes. Just joking, I run all my old gas through my cars including mixed and it is a none issue. I've burned much older gas than 8 months without a problem, but I do add a little octane if it is older.

good luck.


Contributing Partner
I'm with Loren on this one about not using suspect fuel in a modern high tech car - though I am sure you can for the most part get away with it. Industry (gasoline) sites do not recommend using 2 cycle fuel in 4 cycle engines, though they do say using old gas is usually fine if you dilute it with 3 parts fresh fuel to 1 part old fuel. The real problem with old gas is the gummy deposit that forms with the volatile portion evaporates. So if the tank was well sealed and not much evaporated, there is less of a concern.

My choice for using up old gas has always been the lawn mower or the snow blower. Seems much safer than risking the outboard or the family car.