It’s not just Mack and his lawnmower’s mechanic that are saying ethanol is bad for lawnmowers and other small engines. An article on MSNBC is also discussing the trend. (Of course, you should have believed Mack, but for the doubting out there…)

Benjamin Mallisham, owner of a lawnmower repair shop in Tuscaloosa, Ala., said at least 40 percent of the lawnmower engines he repairs these days have been damaged by ethanol.

“When you put that ethanol in here, it eats up the insides or rusts them out,” Mallisham said. “All the rubber gaskets and parts — it eats those up.”

However, an ethanol trade group disputes this, as quoted in the MSNBC piece (as you might expect – they have a vested interest and thus should be deemed suspect).

“Tests completed on lawnmowers, chainsaws, weed trimmers and blower vacs with ethanol fuels showed no engine failures, no unscheduled maintenance and good performance,” the association said.

What happens in the engine, according to mechanics, is that

“the alcohol actually dissipates the oil. So on a two-cycle engine, you’re lubricating the engine, but the oil is being pushed away, so it’s actually not lubricating the engine.” That creates a gummy residue, called shellac, that clogs filters and hoses.

The gummy residue not only attracts moisture that can rust and corrode things but it also clogs up the small jets within the carburetor that dispense fuel into the engine chamber itself.

I-65 North, exit 108 at the Nervous Charlie has plain old gasoline, according to Mack, as does the Kwik Sack at Old Hickory Blvd. and I-40 in Hermitage.