Gasoline/carburetor gumming

[Iceni John]

For those of you with gasoline-fueled generators:

I have a 3500W Champion portable generator that is only for emergency use  -  I presently run it every two or three months for maybe one hour total a year, just to keep it in working condition.   I put lots of Stabil into the fuel, and always keep the tank completely topped up.   It always starts on the first pull, and it runs smoothly and without any exhaust smoke even under full load.

What do you do to prevent carburetors from gumming and eventually needing to be cleaned out?   I heard that one could turn off the gasoline's petcock into the carb and starve the engine of fuel as it was running, and this would leave the carb empty and prevent gumming problems.   I tried that yesterday, but it was misfiring and spluttering so much I didn't dare leave it running that way until it ran out of fuel, so I turned the fuel back on.   Is this technique advisable, or could it cause more problems than it cures?

In the long-term I want to convert it to LPG which will avoid this whole potential issue, but for now does anyone here have any ideas for reducing the chances of a gummed-up carb?

Thanks, John

[Utahclaimjumper]

 Sta-bil is the right solution (pun intended) and will protect your system for a full year or more, be sure to run the engine long enough to pull the treated fuel into the carb.>>>Dan

[sledhead]

With the corn crap they are putting in gasoline to day sta-bil will only last 3-4 mths    dave

[luvrbus]

The red bottle Sta-bil is mostly alcohol use the marine grade but a premium grade gasoline work good also me I drain the carburetor then run paint thinner through the line and bowl area works for me here in AZ turn the gas on starts every time

[Iceni John]

Thanks, good advice (as always).   I'll do that.

John

[Hobie]

So what is the hot tip when the gas goes bad without Stabil and gums up the carb?   Ditto to the ethanol, wrecks the carb gaskets and puts a yellow dusty film inside the bowl.   Can't buy non-ethanol gas here in Calif.  ( don't want to go to airport  

[Gerry H]

   I asked that question to a guy that fixes lawn mowers weed wackers small engines etc and he said it's a lose lose situation and there is no best way. He said using gas and stabil will eventually lead to gum/build ups and that draining/running it dry, will dry out the gaskets causing vacuum and liquid leaks. He said gas and stabil was his preference, keep the gaskets wet. YMMV Good Luck!    Gerry H

[opus]

Not happy with Sta-bil.  I have had to take apart 4 carbs this year.  What I do on my generator, which is the same as yours is shut the petcock and run it out of gas.  I've never had gas do this to me over a winter until I used Sta-bil.  No more for me.

[Ed Hackenbruch]

I have been using Sta-bil for 9 years in my truck and car that i leave in storage in Yuma when we leave for the summer. Usually gone for about 6 months, so far have never had a problem firing them up.  I put in 2-3 times as much as they say you need to use, i figure with the summer temps being so high and with the chance that i might be gone longer than i think, that using more might be a good idea.

[wg4t50]

Started in the working world as a mechanic in a small engine shop, later I thankfully got into the Onan emeragency generator world, been in it for 40+ years, so I have became very opiniated on this very subject.
Have found the very best results are from using a good brand name high test gasoline, I only use it in my small gas engines, and never have an issue. That includes the chain saw, that I mix a 1 gal can of 2 cycle mix that lasts about 2 years, used mostly for cutting up pallets for dumpster.
Also the 18 hp engine on lawn mower, it sits all winter, nothing special, maybe 5 months with zero issues. Everything else is diesel 
I do not like additives, and from flying, the 100LL gas in airplanes lasts a very long time sitting in an airplane, again it is a high octane and has a very long shelf life, the auto hi test is less octane but still a much higher life than cheapest gas.
As said, I am very opiniated. I do what works for me.
FWIW
Dave

[Oonrahnjay]

(snip)  I do not like additives, and from flying, the 100LL gas in airplanes lasts a very long time sitting in an airplane, again it is a high octane and has a very long shelf life,

     Yes, and there's no ethanol in it (ethanol doesn't have high enough "vapor pressure" - it would boil in the fuel lines at altitude).  @ $5.00+/ gallon it's expensive but it is much more stable in a carburettor than autogas.  Also, going to the airport to buy it is a PITA, thank goodness my local airport has credit card-serve yourself pumps and it's small enough tht I can drive up to within 25 feet of the pumps.

[belfert]

There are two gas stations near me that sell non-oxygenated gas for small engines and the like.  That is all I use in my small engines these days.  I've heard it recommended that you put Sta-Bil in your gas as soon as you buy the gas before it starts degrading.

I run my engines dry for the winter, but I had a heck of a time getting my pressure washer started this fall after sitting a year.

[buswarrior]

My way, on the recommendation of a good friend who is into small engines.

I put the appropriate measure of Stabil into the gas cans before the trip to the gas station.

All the gas that goes through the small engines is treated all year.

22 HP commercial mower that does close to 30 hours a year, a leaf blower that sits around, a chain saw is used in bursts, with long periods in between, 3K generator that sits around.

Also, we dose the various family hobby cars according to the measure, which I host in the garage for the winter.

The gumming troubles, which show up as poor starting, are much less frequent than when I didn't.

For instance, the leaf blower starts on the 2nd or 3rd pull anytime of the year for the last 4 years, since the last servicing. There are certain snow conditions for which it is more useful than the snow shovel.

Real, or imagined, I will continue.

happy coaching!
buswarrior

[junkman42]

For those that will use 100LL aviation fuel bear in mind that it has a really high lead content as compared to auto fuel of bygone years.  Also 100 octane fuel because it burns slower than normal auto fuel can play hell with high rpm 2 cycle engines.  If u use this fuel as I do in some of My street rods just remember lead and cats do not mix very well!  Just My take for what its worth.  John L

[opus]

Mysterious how all my cats have fallen off.