Re: [A/S] Gas for your tow vehicle

["Tom" <tmeeker@xxxxxxxxxxxxxxx>]

This is pretty easy to understand.

The lower octane of 87 contains more ingredients that makes the fuel burn
hotter.  This is either ethanol or methanol, I confuse the two, sorry.
Using the 89 or 'Plus' grade will burn cooler and therefore more evenly in
both a cooler and especially a hotter climate.

If you lived in the desert you'd certainly want to use 89 octane.

John Deere did a study a while back due to the frequency of repair on burned
pistons in their lawn and garden machines that used gasoline.  They found
that the lower octane fuels contained more alcohol, it burned a lot hotter
and this caused the aluminum pistons to develop holes in them which cost
lots of money to the company as these machines were under warranty.

The dealers then began recommending to their customers to use 89 octane
instead of the 87 published in the manual.  True, 87 octane will run the
machines and it will power your car *but* you are better off to use 89
octane for a cooler running engine that will also give you better mileage.

If you want to do a test for yourself and you own lawn equipment, change
over to the 89 octane and you will notice a big difference in the amount of
gas you use versus the 87 octane.  Alcohol has less power when burned than
gasoline, and it burns hotter.  Stands to reason that a cooler burning fuel
will make your equipment last longer and it will also use less fuel.

The mechanic on that show is correct.

Tom
WBCCI 5303