you need to put stabilizer in the ethanol treated gas. It will turn to varnish in short time. If you let it sit in the carb of the gen for 5 months with probably need to clean or replace carb.

Non ethanol gas as we get here in SC lasts a bit longer. Maybe a year or so.

I run my carbs dry during storage and drain the tanks on my equipment. been doing it 35 years. Never had an issue with gas varnishing the carb.

When I lived in NJ because its all ethanol gas I would always add stabilizer to my 5 gallon can I bought. Id go through 10-15 gallons a year with all the yard equipment I had.

This is added to the 40-1 or 50-1 mixes I used also.

 

You can't let a machine sit for five months with plain auto gas in it. That is just asking for trouble. One problem with your generator is there is no way to shut off the fuel while leaving the generator running so you'll always have fuel left in the carburetor. Using fuel stabilizer will help but the gas will still eventually go bad so you'll still need to run the generator regularly and make sure you put a tank of fresh gas in it at least once a year. Another option is to open up the case on your generator and install a fuel shut off valve between the fuel tank and carburetor. This will allow you to turn off the fuel while the generator is running and run most of the gas out of the carb.

As for the surging after running a while. Make sure you have the vent on top of the fuel cap open/on if it has one.

 

It almost sounds like it's not getting fuel delivered to the carb bowl fast enough if it runs fine for a bit and then starts surging. I'd pull the bowl and check fuel flow through the inlet needle.

Stabilizers and treatments can help a little with ethanol gas but they don't do much. Even stabilized ethanol fuel causes severe corrosion in months and the fuel won't combust enough to run the engine much sooner than regular gas. In my generators, I only use non ethanol fuel and I like to use stabilizer, shut the fuel off, let it run dry and then clear the bowl. Then I start them up every other month or so and let them run a few minutes, plug in a load and let the field rejuvenate, then shut the fuel off and let it run out and clear the bowl again. Sometimes I let it run out and put the choke on as it runs out to help it clear the bowl but that does leave some gas in the bowl that way. The treatments that claim to cure ethanol gas do not work. They help a little, but they don't solve the problem.

 

I went through the same scenario awhile back with a brand new generator. After having the carb replaced by a professional I follow Lawrosa's formula almost to the letter. And since that time I have learned to start my generator once week and let it run about 5 to 10 minutes and then let it run out of fuel until it stalls adjusting the choke to make sure the carb gets empty. I do not use the shut-off switch. This has become a routine for all my gas driven equipment. And I store all equipment "dry" in the tank and carb.

To the OP...You may be able avoid a costly repair if you act soon. Remove the carb and using compressed air from an air compressor, blow out all the orifices and tubes. That may be enough to put it back into working condition. I've revived several items that way.

 

Thank you all!

As soon as I posted this and went back out to start it again, the generator ran fine for hours till we got power going.

Side note: power outage was caused by a tree on our property fell on the power line from house to pole, pulling off 2 of 3 leads at pole, tree was still on the line.

(besides the 2 tree guys that cut the tree branch off, for the power part of it -it took 5 guys & 3 trucks, 2 were bucket trucks, both were up there on the pole.... and they were there for 1+ hour. Don't think they were milking the situation - there's still people without power a day later). I really know how to break things : ) !!

I remember as a kid in my teens (I'm 58? now), my dad would pull out our Ariens snow blower in the summer and run it a while. It's noisy and I'd be kinda embarrassed someone woudl see that - a snowblower running in the summer.

now 40+ years later, I have that unit in my garage and it works. And it started up fine after sitting for years unused : )

I heard of (not sure if it was from my dad) to run things dry. I added a shut off valve on a couple things.. but don't use it all the time (hang head in shame).

Gotta be more dilligent. THANKS for all the info!!

And I have to mention ('boast'?) also.... I have a 10 year old? 6000w generator that sat a long time unused (fortunately no power outages). Wanted to test it a year ago? and it didn't start. I cleaned carb bowl / drenched it with carb cleaner. but didn't start. Ran only when I'd spray the starter fluid

So that's why I got the inverter - as a spare. I ordered carb parts for the generator and never did anything with them,

Finally had time yesterday, took off carb and took out the 'jet' at the bottom and it was partially closed. Cleaned it and the bigger generator started right up : ) I'll break my arm patting myself on my back!

Brings up another question - if you do all that you guys mention, do you ever proactively take apart the carb to clean it if unit is running OK? I didn't take the float off. Just the jet screw, sprayed carb cleaner and wiped red? stuff from choke plate, passages (gumming from fuel?) What more would you do to 'clean' a carb?

What parts do you replace?
I replaced the bowl gasket, the washers around the drain screw and around the bottom bolt. the washers - 1 was fiber, 1 metal looked fine.

Didn't have the 2 fiber gaskets between carb and engine and carb and air filter. I guess I'll order them and replace.

 

One thing I do is use aviation gas (100 LL). It can be stored for long periods without creating varnish. It's more expensive than auto gas but it's great for items that don't get run very often and you don't have to run the fuel out of the carburetor.

Because it's aviation fuel you can only buy it at an airport which can be inconvenient but a 5 gallon jug could last you a year and is great for line trimmers, chain saws and other small tools. Because it contains lead it should NEVER be used in anything with a catalytic converter or electronic fuel injection as it will kill the oxygen sensors.

There are other "premium" gasoline, often sold in quart containers, that have similarly long storage ability. It can be bought in many home centers and power tool dealers but it's ridiculously expensive. It's an option though if you dump or run out the auto gas when you're done with your generator and just put a quart of the premium canned fuel in. Just make sure you run the generator for 20 minutes to pull the new, good fuel into the carburetor and purge out the auto gas.

 

av gas?! the place I know in PA is right across street from an airport in Allentown. I thought all av gas is types of kerosene / other things not really gasolin?

But then you got to the part about lead? They allow lead in any fuels these days? Never would have thought that.

For anyone interested and doesn't know, I found this site a while ago for where to get non-ethanol gas.

https://www.pure-gas.org/

Yes! Those cans of gas are expensive : ) Might pop for the 40:1 / 50:1 cans. but not the straight gas ones : )

 

I've noticed more and more station are getting non-ethanol gas at one of the pumps.