Good for cars, Bad for boats

In a Reuters report, U.S. President Joe Biden will unveil plans to extend the availability of higher biofuel blends of gasoline during the summer to curb soaring fuel costs and to cut reliance on foreign energy sources, senior administration officials said.

The measure will allow Americans to keep buying E15, a gasoline that uses a 15% ethanol blend, from June 1 to Sept. 15. While E15 is only 10 cents cheaper on average and is less “energy dense,” meaning drivers would need to buy more fuel, it should still help lower expenses, the officials told reporters on a call previewing the announcement.

However, what Reuters omits is the danger of E15 on boat engines.

According to BoatU.S., E15 gasoline — fuel blended with 15 percent ethanol — is prohibited by federal law for use in boat engines and voids many engine warranties.

Ethanol in gasoline is a problem for boats due in part to phase-separation. When moisture is introduced to an on-board fuel tank because of variations in temperature, it binds with the ethanol and settles as sludge in the bottom of the tank. Ethanol has also been known to be corrosive to metal fuel tanks and engine components.

Worse, the labeling of E15 at the pump has in the past been confusing, and just because it is approved for sale does not mean it is safe. Check your engine specs before using.