I give up. What is oxy gas?

oxygenated fuel or 10% ethanol. thought everyone called it oxy gas? all stations only sell ethanol gas in mn. non-ethanol gas is rare.

I've never heard the term "oxy gas" either.

I saw a new product at Depot yesterday. It is to treat ethanol laden gas. I figured I would try it. Not sure how it differes from others like Sea Foam.

It is most likely a carb problem and/or fuel filter problem. Most small engine manufactures recommend that you change your fuel filter, air filter, and spark plug annually. They also recommend you change your oil every 25 or 50 hours (at minimum annually). If you have never tuned up your mower, now would be a good time to do so. As for the fuel, if you have never used a fuel stabilizer or drained gas tank during winter storage, I recommend draining the gas tank, put on new fuel filter, drain the gas in the carb bowl (there may be water in bowl), and fill tank with fresh gas. Start it up to see how it runs. If it still doesn't run right, and the air filter and spark plug have been cleaned/replaced, then you'll have to clean carburetor at this point. Also use fuel stabilizer in your gas if you don't plan on using mower in the next 30 days (i.e. winter). Sta-bil Marine formula is a good preventer of the damaging effects of ethanol.
http://www.goldeagle.com/brands/stabil/default.aspx

non ethanol gas is available for boats, collector cars, and such. have to look for it. store by me has it in 91 octane rating. not sure what "treating" the gas does. how can it hide or negate the effect of ethanol? i am no chemist. back to my mower, does running the tank dry allow crud into carb? hard to clean out gas tank. sure you can unbolt it and flush it out or try and drain it out.

Just switch back to 87 octane 10% ethanol blended fuel. There's no benefit to running high octane gas in a mower motor.

I doubt that either the level of oxygenation or octane level impacted performance. Chances are it is something like olf gas that is less volatile or it had some crud in the gas can.

At one time several localities required the use of oxygenated fuel in wintertime to purpotedly reduce pollution. I understand the number of localities with that requirement are very few now, likely because 10% ethanol fuel is the standard.

'There's no benefit to running high octane gas in a mower motor.'

There are some. Mid and Premium gas has more goodies.

' Chances are it is something like olf gas that is less volatile'

This is why I use mid-range gas. Two gallons lasts me for 60 days. It stays out in my hot shed with the mowers. Every time I open the can, pressurized fumes are emitted. These fumes are made up of the volatile elements. The fuel already in the mowers emits it's volatiles in a quieter way. So, I use higher octane in the effort to preserve at least minimum octane for the duration of the fuel, plus take advantage of he extra additive components.

Marine formula Sta-Bil for ethanol fuels works by preventing the corrosion associated with moisture absorption of alcohol. I don't know how it does this but I trust Sta-Bil and use it in my automotive equipment as well as the OPE. It also is of course a stabilizer and has a cleaner package.

joe mn-Thank you for the clarification. FWIW all the pumps in my area say "May contain up to 10% ethanol". I also use mid-grade (89 octane) in all my equipment, which around here is $.10 more a gallon, because my Echo trimmer calls for it. I also use Stabil in all my OPE gas at about double the standard dosage. I think I am going to switch to marine Stabil starting next year. Some of the equipment I don't drain during the off-season (November through April). So far I've never had any gasoline related problems and some of the equipment is over 10 years old.

"There are some. Mid and Premium gas has more goodies."

Which goodies are present in 93 octane gas that are not present in 87 octance gas that would make a lawn mower engine start easier, last longer or run more efficiently?

Joe_mn, you said "back to my mower, does running the tank dry allow crud into carb?"

I typically disconnect the fuel line at the carb then remove the gas tank. The gas from the tank can easily drained into a container. I recommend draining the gas with the fuel filter connected to prevent dirt/debris from getting into container. Then you can dump the container of old gas in your car's gas tank. The higher amount of fresh fuel in your vehicle will help burn off that old gas. Then remove the fuel filter and throw it away. Use compressed air to blow out the fuel lines and gas tank. Turn the gas tank upside down to blow it out. Then put everything back on with a new fuel filter. The fuel filter is designed to stop any dirt/debris from getting to the carb, so you don't have to worry about crud.

i do not have a filter on my mower. the non-ethanol gas is only available in 91 octane. no lower octane stuff. mower ran fine this past weekend. no primer bulb. it usually takes 4 pulls to start. funny. never less.