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av gas in mower

s and s mowing

LawnSite Member
anybody ever hear of running avaiton gas in a mower,was at dealer yesterday and he told me the local airport brought there ztr in for service and it has been run on av gas only,he said pipe was clean as he had ever seen and engine had several hundred hours on it and was in great shape.thinking of trying a few gallon in my exmark kohler,what ya think?


LawnSite Silver Member
av gas can be a bit dry - mighty high octane - probably 100 or better. I think you are better off with premium -about 92 octane. I have read or heard you do not want ethanol in small engines, and that may or may not be true, so I just use amoco premium. Just my opinion. Thanks, Brad


LawnSite Member
SE Mich
Expensive and unnecessary!

Maximum efficiency is achieved by running the lowest octane possible. Octane is only a measurement of resistance to detonation

Metro Lawn

LawnSite Silver Member
Stay away from the AV gas. They must have been running low grade because the good stuff is about 130 octane, enough to melt your engine down


LawnSite Silver Member
not that I personally care, but AV fuel is not legal to use for non AV purposes.


all degree

LawnSite Senior Member
Neptune NJ
Wrong Geo. (and this is the business i am in) Its sold in many markets at the pump along with regular grades for the consumer. Most popular use is jet ski's and high performance boats.

The comments about mowers are right on. AV gas is not good for small engines and will make them run extremely hot. Anything higher than 87 in a mower and you are just wasting money.


LawnSite Member
Tyler, TX
I dont know where some of you guys are getting your information. I run Vp C-12 in my KTM dirtbike and have been using some form of race gas in my bikes for 30+years. Race gas does not make your engine run hotter..as a matter of fact, the flashpoint of race gas is much lower than regular/ supreme unleaded. It burns cooler...which is why it will not make as much power or be as efficient ( quicker to burn, but not as hot burning) as regular unleaded in a low compression engine. Its advantage is for high compression engines that need cooler burning fuel and a low flashpoint to avoid detonation. Run the lowest octane your engine will survive and not detonate on. Anything more is a waste.
There are more than a couple of grades of av gas as well. But all have modifiers , additives, and stabilizers for high altitude (icing) conditions. I have never run avgas, know some guys that have and I've heard totally different opinions on it. This might be due to the different formulas of avgas , engine compression, etc.