Storaing a generator ... With or without fuel?

Factual Questions
1

A year ago I purchased a generator. I needed it during Sandy. As I put it away, should I leave the gas tank full or empty?

I’ve heard that fuel decays a bit over time. I’ve never had trouble with a lawn mower in the spring.

Oil and water don’t mix, but Ethanol and water do mix. I’ve heard that sometimes trace amounts of water can get into fuel and may rust the inside of an engine given enough time.

I fire it up every 4-6 months as a test. Is this necessary? So far, whenever I use the generator, I’ve run the tank dry. Is this the best course, or should I leave it full?

2

Use some of this stuff.

3

I wouldn’t leave it full knowing that there is a low chance of using it over the next several months. If you typically need to use it a couple of times a year at least, you should be good keeping it full, with the additional of a fuel stabilizer such as Sta-Bil.

4

The manufacturer doesn’t recommend it, but I have had no problems keeping mine full, using it no more than once every couple of years. I use a fuel stabilizer like those mentioned by Dorjan amd leftfield6.

5

I tend to leave my various gas powered tools/machines empty if they have a plastic gas tank, and full (with stabilizer) if they have a metal/steel gas tank.

Steel tanks can rust when empty as ambient moisture builds up, particularly during winter, so I keep my motorcycle full to the brim over the winter.

For my lawn mower - plastic tank - I empty it. And I empty my snow-blower (also plastic) during the summer months.

Stabilizer is fine, but I’ve had various equipment rendered inoperable due to stored gas (even with stabilizer in it) eroding various plastic/rubber intake tubes, gaskets, etc. Past culprits have included a weed wacker and a chainsaw.

6

I keep fuel in my Honda generator. It has a small fuel pump inside that I don’t want drying out.

I use stabilizer. I siphon out the gas and put in fresh every six months. Ethanol just doesn’t hold up well like pure gas.

7

One good way to avoid gasoline problems is get/convert a generator to run on propane or natural gas.

8

I don’t think a little rust in a gas tank would be bad.

I use fuel stabilizer when storing power equipment for a few months but I don’t trust fuel stabilizer to work for years on end.

Rust on the cylinder would be bad, so I remove the spark plug and drip a little oil into the cylinder if the engine won’t be started within 6 months.

9

run it dry. keep fuel on hand in a can which you refresh every month or two (use the month old stuff in your car).

10

I keep mine full, with Stabil, and test every Saturday. I don’t need to hit the start button in the middle of an ice storm or other power outage, only to find that something doesn’t work. That’s not the time to fix it.

Ethanol in gas does absorb water, which will make its way to the bottom of the tank, and into your float bowl and carburetor. Poor running at best, no running at worst, and rust in tiny places you don’t want it. Gasoline without stabilizers will create a thin varnish on the interior surfaces of your carb, and deteriorate performance, or prevent the engine running completely.

At the very least, use a fuel stabilizer and run the carb dry after testing.