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Encounters With Ethanol


In 2003 several states switched their on-the-water gasoline from the traditional methyl tertiary butyl ether (MTBE) blend to one containing ten-percent ethanol, called E10. Ethanol is derived from agricultural products such as corn and sugar cane, and its purported ability to reduce greenhouse gases has led, in part, to its use at both on- and off-highway fueling stations.

Scientists and some politicians claim this new blend can reduce American dependence on foreign oil, while critics note that producing it requires petroleum-based products like pesticides, fertilizers, and fuel for farm equipment. Ethanol supporters believe that as agricultural technology improves and a greater number of ethanol-friendly crops are grown, the need for these petroleum-heavy products will be reduced, making ethanol both truly green and cost-effective.

Of course it's hip to be green, and boaters want to help—anything to reduce our carbon footprint. But in states where ethanol has been implemented for several years (around half of the United States now uses E10 fuel), another one of this fuel's other talents has come to light: it's an excellent solvent. It even has the disconcerting habit of partially dissolving fiberglass fuel tanks and rubber hoses.

This problem has been well-documented by organizations such as BoatUS, which has done a wealth of research and testing regarding the effects of blended fuel on various boat components. (You can see the results of its testing at BoatUS.) And to date, boaters have filed millions of dollars in class-action lawsuits against oil companies for failing to fully disclose the potential ill-effects that E10 fuel could have had on their vessels.

PMY recently caught up with two Northeast-based boaters who have personally felt the sting of ethanol and agreed to share their stories with us.


A boat owner from Long Island, New York, who wishes to remain anonymous, purchased a brand-new 36-foot center console, complete with triple 275-hp Mercury Verado four-stroke gasoline outboards in 2007. He'd stepped down from a Viking 50, and had dreams of catching big wahoo on his brain. In particular he was looking forward to the warm Northeast summer boating season followed by winter-wahoo chasing in the Bahamas.

His Florida-built boat had just arrived in the Empire State for the spring, and I saw her at my marina over several weeks as an array of top-notch electronics were installed. She looked ready to prowl the deep, and her owner beamed like a proud father. But the pride didn't last.

Within five months of taking delivery, his engines started to stall and sputter. An investigation into the cause followed. He eventually discovered residue floating around in the two, nine-foot-long, 175-gallon integral fiberglass fuel tanks, which are shaped and contoured to the hull to maximize their capacity. (The boat's 175-gallon center fuel tank is aluminum.)

The residue, which he described as looking like small chips, turned out to be resin from those integral tanks. In less than 180 days, the ten-percent ethanol-blend gasoline had separated out the resin, which worked its way through the fuel system and eventually fouled his motors.

This owner, distraught about his new pride and joy being sidelined, was concerned about how to properly fix the problem. He knew he couldn't go to the engine manufacturer because, as he says, "They didn't do anything wrong."

After working out a deal with the builder, the boat was returned to the factory where the fuel tanks were repaired and a liner was installed in them to prevent a repeat performance. The motors were given the green light, and the boat was re-sold by the builder.

The owner is currently awaiting a new boat from the same builder, which is expected to be delivered sometime early this year and will be outfitted with three aluminum fuel tanks. (Aluminum and polyethylene fuel tanks shouldn't be affected by E10.) His new boat should be trouble-free running on the current ten-percent ethanol gasoline, but it comes at a cost of fuel capacity. The two outside aluminum tanks will accommodate 100 fewer gallons since they can't be shaped like integral fiberglass tanks. And of course, this results in reduced range for his 36-footer. Moreover, he's been forced to spend the last two seasons dockside, only dreaming of wahoo.

This article originally appeared in the January 2009 issue of Power & Motoryacht magazine.