Some very old 2 cycles will burn through pistons on e10 if you “drive hard.Fake news. See the chart below. Ethanol burns much cooler than gasoline, over 110*F cooler. The real reason to avoid ethanol in equipment that doesn’t see regular turnover of its fuel tank is that ethanol is very hygroscopic; this means it attracts water. Water does not burn and higher ethanol content fuels can become saturated with water and cause problems.
You burn through pistons because the fuel delivery (carb or injection) is not adding the correct amount of fuel and is therefore lean; stoichiometric on gas is 14.7:1, E85 is like 9.7:1, so you need a LOT more fuel to keep the combustion “happy”.Some very old 2 cycles will burn through pistons on e10 if you “drive hard.
My Subaru 360 is one example as it is a lean burn automotive 2 cycle. On e10 you need to change the dizzy and timing, along with the spark plug gap and the enrichment AFR on the carb.
On a hot day if you don’t you can get quite a bit more power at the top end, turn more rpm’s before it self limits and potentially burn through a piston.
The reason this is is more to do with being able to overrev and generate more power than intended coupled with lean burn, no oxygen sensor and running near the edge to begin with.
For a governed piece of lawn equipment the above is very unlikely unless you regularly take your v twin lawn mower to 8000rpms
Yes and adding more lean is asking for trouble.Newer small engine run lean anyways due to the fixed jet carburetors and EPA reg.
This sentence made my brain fibrillate.Yes and adding more lean is asking for trouble.
This still won’t address the hygroscopic tendencies of ethanol-containing fuels.They really should build them tuned for E10 since that is what almost everyone will be using. Why should you buy a new mower then have to search for antique-compatible fuel?
You burn through pistons because the fuel delivery (carb or injection) is not adding the correct amount of fuel and is therefore lean; stoichiometric on gas is 14.7:1, E85 is like 9.7:1, so you need a LOT more fuel to keep the combustion “happy”.
As the nitrous guys used to tell me when I first started racing, “lean is mean (on parts), but fat is where it’s at”. Lean will usually make more power, all the way up to just before the point you’re helping the cleanup crew pick up chunks of your engine off the track surface. The problem is that line is so thin when you chase it you’re playing with razor blades.This is the answer on a larger scale. Not sure E10 will cause the issue but from my racing days @SubieRubyRoo is correct you burn a lot more alcohol than gasoline when everything is the same.
Just my $0.02
FWIW any newer OPE that I’ve purchased says E10 is fine. The issue historically has been that ethanol is hydroscopic and will destroy fuel lines in older equipment.
My old John Deere F510 had a non vented fuel system. Never drained the gas or had water issues in 24 years of E10 use.This still won’t address the hygroscopic tendencies of ethanol-containing fuels.
Kind of.View attachment 168552came across this article the other day. I assumed 100% ethanol burns faster and hotter, possibly. But would 10% really makes that big of difference?