Ethanol May Be Harmful to Your Lawnmower

Frank Williams
by Frank Williams
ethanol may be harmful to your lawnmower

OK, so this isn't specifically about cars, but it could have ramifications for anyone who uses gasoline. reports small-engine mechanics around the country are reporting an increase in damage in boat, lawnmower, chainsaw and other small engines. The culprit? They're saying it's the ethanol blended into gasoline. Apparantly it creates a gummy substance that "clogs valves and causes small metal parts to rust, destroying carburetors and other crucial components". The bad thing is, even if you drain the tank, this residue remains behind and does its damage. The same thing happens in our cars, but they're designed to handle "a certain amount of the residue that causes so much trouble in smaller motors." No one's done any studies to substantiate these allegations, but "a growing chorus of mechanics" say it's so. [Thanks to ppellico for the link]

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  • Mrclean Mrclean on Aug 31, 2008

    Ok, here it goes. Methanol readily mixes with water and will corrode things in your engine. Heck it even draws moisture from the air! But, Ethanol will not collect as much moisture especially if you are using a gas/alcohol mix like E-85 in the mower or other small engine. Once mixed with gasoline to make the E-85 fuel, any water drops out and is drained away before you purchase. So the lesson is use Ethanol E-85 that does not have any water in it first of all. 2nd, 2 cycle engines need lube in the fuel, 2 cycle oil WILL NOT mix with alcohol. You'll need to use 4 ounces of castor oil (yes that nasty tasting stuff Mom gave you as a kid) or 4 ounces of mineral oil per gallon of alcohol fuel to make a 2 cycle mix. Small engines LOVE alcohol fuel as it carries some of it's own oxygen. Just remember to use a fully synthetic motor oil in the crankcase. Undoubtedly, most of the boat engine mechanics are repairing 2 cycle engines that the owners had unknowingly tried to mix 2 cycle oil with the alcohol fuel. 4 ounces of castor oil mixed per gallon of alcohol will do the trick.

  • Happy-cynic Happy-cynic on Aug 31, 2008

    We had local news reports of boats and engines of all sizes having trouble with E10 fuel. ( l live in MA USA) My personal experiance with small engines has been no issues. ( had landscape business and worked on private estate for over 10 years) (To add to the posts of "care and feeding of small engines") I have an 18 year old 5 HP Tecumseh engine attached to a 40+ year old Bunton push mower. I have used it to cut my own lawn (less the 1 acre) and for two years in landscape business. Never had a problem with it. The key is to buy gas from major brand, change oil in the fall, run the engine to it stops at end of season, and store in a dry location. Speaking of gas, when I had my landscape business, I noticed that when using off-brand gas, my gear would not run as good. The big mover would back fire and the small stuff, (weed wackers,etc) would take more effort to start. As the previous posters have mentioned There are other options for lawnmowers beside gas Depending on size, there is electric, or push mover (small plots) (It might seem strange but the reel mowers cut the grass better then your typical mower. Just imagine getting a haircut by having some one pull your hair and tear it vs. snipping it.) to large tractors, (Kubota, John Deere) It is well worth checking out are the walk-behind tractors. We fossil fuel buffs face an Hobson's choice. The main reason why it was taken out was due to groundwater conditions. Easier to adjust to E10 then cancer

    • Eth Doc Eth Doc on Feb 01, 2012

      Hi, what brands are you using? Could it be that you have really high quality machines and there Ethanol is not causing any damage to your machines? Or is it possible that the climate if favoring easy maintaining of your machines / humid climate is more risky to troubles caused by Ethanol. ...

  • Onlinetarzan Onlinetarzan on Aug 13, 2009

    This problem is real, it is annoying, and it can be expensive. Fixing a lawnmower after ethanol has gunked up everything is a nightmare. Corn taste great to eat and dinosaurs didn't die and turn into goo so that we could use something that goes well with burgers as our fuel. Check out my experience and solution:

  • Woodsmower Woodsmower on May 19, 2010

    Have any of you tried sta-bil? found some info on that here: