Portable Generator: Gasoline Stability

[sourdough]

There are probably many posts concerning this, but...

I have a Craftsman 5.6 KW portable genset circa 2008. I start it every fall/end-of-summer (just ran it today) for an operational check for about 1 hour and refuel it to top the tank off for use in Winter if we have a power outage. It sits for the next 12 months, usually without a start unless the power fails, which is seldom to non-existant. The genset is stored in a garage that never goes below 40*F or above 80*F.

I have heard about how gasoline goes bad after a year or so, but have not experienced that.

Please tell me how my up-to-7-year-old gasoline mix survives without a hitch.

My BIL is of the understanding that "premium" gasoline (90+ octane) reverts to regular 89 octane after about a year. I call BS but am ready to be enlightened.

Jim

 

[Mustang51js]

Try that with a new tank of gas. I just had to remove and clean the carb on my motorcycle from two month old gas.7 years ago didn't have all that ethonal added to the gas. Now when I'm done with something I turn off has and let it run dry and put stabil in tank

 

[theoldwizard1]

Keep doing what you are doing, just do it more often, every 2-3 months. Make sure you put a load on both sides of the output. Do NOT refill until it is almost empty.

 

[Askme42]

Try that with a new tank of gas. I just had to remove and clean the carb on my motorcycle from two month old gas.7 years ago didn't have all that ethonal added to the gas. Now when I'm done with something I turn off has and let it run dry and put stabil in tank

Many places still carry ethonal free premium.

 

[nu2me]

The fact that you don't have temperature extremes works in your favor, but seven years is nothing short of miraculous. (Then, I've had batteries in summer cars that lasted seven years, too.) I used to work on gennies and other small engines for a fleet, and wouldn't think of diagnosing a no-start or runs-like-s*** complaint without eliminating the spoiled fuel variable first.

Winter gas has more volatility (to light off faster), summer gas less (to avoid vapor lock). Ethanol tends to draw water out of the air and puddle it in the bottom of the tank. And it doesn't even smell, anymore.

I'd second the 2-3 month statement, and I'd just dump it if 6 months or older. There's more chance of contamination with small engines because dirt gets in when it's transferred, especially from rusty metal cans and who knows what's inside a flex-spout. The insides of sheet-metal fuel tanks also get rusty, especially if they're empty. I used to cut a 1/4" clear plastic paper filter into the line from the tank to the carb to strain out rust/grit and make it easier to find evidence of water. [e.g., NAPA 187723]

As to the matter of loading small generators to periodically exercise them, and for making adjustments, 1500-watt milk-house heaters (available at garage sales and Goodwills) are excellent -- just inspect before using.

 

[c4cruiser]

There are probably many posts concerning this, but...

I have a Craftsman 5.6 KW portable genset circa 2008. I start it every fall/end-of-summer (just ran it today) for an operational check for about 1 hour and refuel it to top the tank off for use in Winter if we have a power outage. It sits for the next 12 months, usually without a start unless the power fails, which is seldom to non-existant. The genset is stored in a garage that never goes below 40*F or above 80*F.

I have heard about how gasoline goes bad after a year or so, but have not experienced that.

Please tell me how my up-to-7-year-old gasoline mix survives without a hitch.

My BIL is of the understanding that "premium" gasoline (90+ octane) reverts to regular 89 octane after about a year. I call BS but am ready to be enlightened.

Jim

I have a small gas-powered weed-eater that uses a 50:1 mix and the gas I use for that is about 4 years old now and it still runs fine. Starts on the 1st or 2nd pull!

I know a few people that add "Sta-Bil" to their cars' gas tank when the car isn't used over the winter, but they also make sure that the tank is full. Apparently there is less chance of moisture forming.

FWIW, you can get ethanol-free gas up in Olympia (Acme Fuel in downtown Oly) if you want to try that. I know that in your area, it's possible to go without power for some time because of storms, so it may be worth it to take a few containers to fill up. You can add Sta-Bil to the cans if you like and I don't think there is any problem running that stuff in small engines. When I bought a generator a few years ago, it came with two small bottles of Sta-Bil.

 

[aandpdan]

Many places still carry ethonal free premium.

It depends where you live. In many parts of the US all gas has ethanol.

http://pure-gas.org/

 

[wyliesdiesels]

It depends where you live. In many parts of the US all gas has ethanol.

http://pure-gas.org/

Thx for the link. I cant stand ethanol! Its a complete joke for many reasons i wont go into!

 

[LS6 Tommy]

We're stuck wit hit here in NJ unless you want to spend for the Trufuel stuff...

Tommy

 

[wyliesdiesels]

We're stuck wit hit here in NJ unless you want to spend for the Trufuel stuff...

Tommy

I guess i am too. Only station near me sells 100 octane!

 

[Highbeam]

I've cleaned out big holley carbs full of varnished fuel, I know that bad smell of spoiled gas. But.... I have been impressed with how long gas really does last anymore. I think there is a bit of hysteria involved with the fresh gas requirement. Older gas won't be as good and maybe make a bad running engine run worse but the engine should still run.

 

[sourdough]

I appreciate all of the comments, thanks!

I noticed a few of you disdain ethanol because it absorbs moisture. So does isopropanol, or isopropyl alcohol, marketed as "HEET" for decades. We used it for years in Alaska before the introduction of ethanol in fuel (during the leaded fuel years). Back then I had a Coleman 4K (120v only) genset (for the refrigerator, chest freezer, and the pump/controls for the Weil-McLain boiler for radiant baseboard heat) that ran on leaded regular gasoline and when it was introduced to ethanol, I awoke one night to the smell of gasoline as the ethanol ate away through the deposits in the carb and had to rebuild it. Not much difference insofar as chemical composition: isopropyl alcohol is a slightly bigger molecule than ethanol (ethanol is C2H6O and isopropyl alcohol is C3H8O). So, there should be no "pooling" of water/moisture in the bottom of the tank.

The fuel tank on my genset is plastic as are the 3 5-gal fuel jugs (no rust problem) and I filter the gasoline using a cheesecloth filter as I refuel the genset to within 1/2" of the tank top (takes out any big chunks!) and the unit has a fuel filter. I didn't mention the fact (as suggested) that when I do the annual run-test it is connected to the house and the load is furnace, 2 freezers, a refer, and the septic pump: all primary stuff. We can do with just a few lights and no computer/satellite TV, and can power-share as needed if the power outage is of long duration: secondary stuff.

I used the Sta-Bil treatment that came with the genset for the first tankful, but not since. I will seriously check into procuring more next trip to "town" as we are in the boontoolies as c4cruiser mentioned (Hi, Neighbor!).

Sorry, but I can't see running the genset every 2-3 months under load. When I run it, the fuel cutoff valve gets closed at the end of the run and it shuts off when the carb fuel runs out.

Jim

 

[wyliesdiesels]

I cant stand ethanol for reasons other than the water issue. The energy content is lower, the use of corn to make it causes food prices to rise, and the marketing slogan that it is a green fuel is a LIE. Consider all the diesel fuel spent on tractors used to plant and harvest it! The same can be said of priuses, solar panel, etc. because of the toxic chemicals used to make 'em....