skip the ethanol

[DR Buck]

My dad had a John Deere riding mower with a 20hp kawasaki v-twin.  It dropped or bent a push rod 3 times in the last two years he was alive.  JD dealer kept accusing him of shutting it off at full throttle and causing a back fire. 

My Zero-turn with the 25 HP Kawasaki backfires EVERYTIME I turn it off no matter what the throttle is set at.

[beenthere]

Dr B
Check that the fuel shut-off is working...sounds like it is not.

Should have it if it is fuel injection.

[pineywoods]

My dad had a John Deere riding mower with a 20hp kawasaki v-twin.  It dropped or bent a push rod 3 times in the last two years he was alive.  JD dealer kept accusing him of shutting it off at full throttle and causing a back fire. 

My Zero-turn with the 25 HP Kawasaki backfires EVERYTIME I turn it off no matter what the throttle is set at.

There is a fuel shutoff solenoid built into the carb. Shuts off the main jet when you turn off the ignition. It's probably stuck open with gum left from evaporated fuel or corroded from water in the ethanol.  Look on the side of the carburator.If you see a small wire attached, pull it off with the engine running. The engine should die immediately, if it doesn't the shutoff valve is stuck....

[bandmiller2]

Cappy, even in warmer weather the tractors don't start like they used to.They put something in the fuel so it won;t evaporate into the atmosphere as easily.I'll try to find high test without alky and try that .DanG old tractors I don't want to spoil them,they'll want the good stuff all the time.Frank C.

[John Mc]

The reason that some (not all) high test gas does not have ethanol in it is that when some states were considering mandating ethanol, various groups lobbied to make sure non-ethanol gas was still available. [Some piston aircraft can run on auto gas, but ethanol is definitely prohibited. It's a problem for marine use (ethanol eats some fiberglass fuel tanks, and many boat engines sit longer than cars between use, giving the ethanol more time to suck moisture out of the air). Two cycle engines have a tougher time with ethanol.] Premium gas was picked because it's already something of a "specialty gas" - and because few people run premium in their cars, so making it free stil tended to maximize the use of ethanol-laced gas.

Don't be fooled into thinking that all premium gas is ethanol-free. It's a function of what that state's regs say. And even in some states that allow ethanol free premium gas, they don't necessarily prohibit ethanol in premium gas.

I'm fortunate in my area - even though most gas stations have around 10% ethanol in everything they sell, there are one or two who get their gas from Canada without any ethanol, and a small airport that sells ethanol-free premium auto gas (they don't stock aviation gas). I make a point to buy all my chainsaw gas from one of these sources.

John Mc

[Ironwood]

One more thing to worrry about : Ironwood

[Mad Professor]

I've been running high octane in all of my gas equipment. I've been told that there is no ethanol in the high grades, but cannot verify. Mid grade is a blend of high octane and regular, so I avoid it also.

Don't know who told you that but all auto fuel sold in mASSachusetts is "oxygenated", a.k.a. "corn fed" up to 10% ethanol.

Ethanol will react with aluminum or magnesium (more so) so it will also eat up uncoated fuel tanks and carb parts.