I have an emergency generator for my refrigerator and freezer, and maybe a couple of other small things. I keep it outside, next to the house, under cover.
Long story short, sometimes I don’t test the generator every month. Sometimes I don’t test it every six months. It took me about three days of pulling the rope to get it to fire up. I then ran it until it ran out of gas, changed the oil and in general got it ready for the next six months of waiting for the power to go out.
But where do I keep the gas I’ll need to run the generator the next time I need it? Sure, I have Sta-Bil, but is it better to fill the metal tank on the generator, or leave the gas in an approved plastic fuel jug in the non-climate controlled tool shed? Will standing gas in the fuel line eventually rot the generator’s innards? If I leave the tank dry, do the innards dry out and crumble? Does it make any difference whether the fuel is E-10 or “pure” unleaded, as long as I use Sta-Bil?
Assume that in case of fire, the house is in equal danger, either way.
Gas with ethanol tends to dissolve gums /oils and deposit them into the carburetor. Looks like you already are facing that problem. I would recommend disassembling the carburetor and cleaning it or take it to a small engine place (pressure washer / lawn mower repair).
Use ethanol free gasoline and you can go longer without replacing the fuel. Otherwise do what bizerta said.
I have a generator as well as a boat which are both stored outside from October to May.
My understanding is that when you have any devices that use fuel and you’re not planning to use them regularly you always keep their fuel tanks filled to the max with gas and you also add fuel stabilizer.
The tank should always be kept filled because as the outside air temperature changes around the unit, moisture in the air that is inside the gas tank condenses on the inside walls and flows into whatever fuel is still in there. Water in fuel causes big problems.
Interestingly - I had this discussion with a friend last fall who insisted that I run the tanks dry at the end of the season and refill with fresh gas in the spring. We double checked with the mechanic at our marina and he said always keep them filled when stored.
When I start up after 6 months I immediately add fuel treatment that cleans the injectors / carb and also removes any water. I then try to run the tank empty and refill with fresh fuel.
You don’t say how old the unit is but from what I know, am and biz’s comments are very true for older units, but anything manufactured in the last 20 years should be able to handle fuel with ethanol. Modern seals, gaskets, hoses etc are all treated to withstand it.
Good posts above. Just to add that you should run the generator dry then drain the carb. I found out the hard way that over time you can get the injectors so shellacked that carb cleaner won’t clean it. Mine had to go through an ultrasonic bath.
Or worse you will have a cheap push lawnmower that uses plastic carburetors. Almost all push lawnmowers do now. Those can’t take the shellacking at all. They have to be replaced if you leave ethanol gas in them for more than a few weeks. Sigh.
I bought another mower rather than pour (ha) money into such a cheap design. Even then, I still got a plastic carb, but at least it has a fuel cut-off valve that can somewhat protect the carb.