Talltom
ArboristSite Operative
Ethanol in fuel does not cause pre-ignition (knocking). It increases the fuel's octane rating and reduces knocking. It is also an oxygenator, and E10 has been used in metropolitan areas for decades to reduce smog - it burns cleaner that straight gasoline. It is less dense than gasoline and has fewer BTUs per gallon, but this reduction is slight for E10. It has a higher vapor pressure and can affect the tuning of your saw. Modern autos have computerized engine management systems that can adjust on the fly, a chain saw carb can not. It's biggest problem is that it attracts water, so you need to keep our supply fresh. It's also reported to have detrimental effects on certain plastic and rubber components.
I don't know if the amount of ethanol in gasoline varies greatly over time or by load, but it's about the same price as gasoline, so there's no economic incentive to be precise. On the other hand, they are injecting some very expensive chemicals at the rack when they load the tanker truck, so I'm sure they can be very precise in doing that.
The Government did not force anyone to use MTBE in fuel. That was the industry's decision as a cheap way to boost octane rating when the Government banned lead. Now that MTBE has been banned, the industry is using ethanol to do that & you will be having a difficult time finding gasoline without ethanol. Re-tune your saws and keep your fuel fresh.
I don't know if the amount of ethanol in gasoline varies greatly over time or by load, but it's about the same price as gasoline, so there's no economic incentive to be precise. On the other hand, they are injecting some very expensive chemicals at the rack when they load the tanker truck, so I'm sure they can be very precise in doing that.
The Government did not force anyone to use MTBE in fuel. That was the industry's decision as a cheap way to boost octane rating when the Government banned lead. Now that MTBE has been banned, the industry is using ethanol to do that & you will be having a difficult time finding gasoline without ethanol. Re-tune your saws and keep your fuel fresh.