Phase separation might explain the geographic or sporadic nature of some problems. Two years ago on Long Island, for example, boats that had been running E10 for years suddenly had hose problems identical to those in the Keys. That also happened to be a particularly rainy summer. South Florida is certainly prime territory for water in fuel, but problems occurred even when tanks seemed fine. The key might be that phase separation is temperature dependent. Lake water and seawater buffer temperatures in fuel tanks, but fuel in hoses, filters, carburetors, fuel pumps and vapor separator tanks may phase-separate when temperatures drop — these are costly components that are inexplicably failing on boats using E10. “You’re getting a concentration of all things that damage polymers,” Kelley says.
If water is the underlying problem, is it fair to blame ethanol? New Hampshire’s Lake Winnipesaukee only recently switched to E10, but mechanics there have been fighting water in fuel for years. “A lot of the old carbureted engines could handle a bit of water, but with today’s engines, once it fills up the filter, it stops the motor,” says Jeff Fay of Fay’s Boatyard in Gilford, New Hampshire (faysboatyard.com). “It doesn’t do a lot of damage [in unblended gasoline],” Fay says. “If water sits in an engine for a while, it can damage the fuel system. Some aluminum tanks get pinholes in the bottom [where the water collects]. That’s a problem with or without ethanol.”
South Florida also has long had problems with water in fuel. “My phone has been ringing off the hook for 35 years. Ethanol just made it ring more,” says Skip Trent, whose business is removing contaminants from gas and diesel tanks from Miami through the Florida Keys. “There are only four ways water can get into a tank: through the vent, through the fill, around the [fuel gauge] sender or from a hole in the tank.” Loose gauge senders or improperly plumbed vents are common culprits. Water enters fills when oversize mounting screws, like oval or pan-head, protrude so high they keep fill caps from sealing, or when cracked or missing cap O-rings go unnoticed. Some brands of plastic fills — even on expensive boats — crack from sun or overtightening. “Every time it rains, you might as well have a funnel in the fill,” Trent says.
Unfortunately, when E10 phase-separates, it loses one or two octane points, so it has to be discarded. “With [unblended] gasoline, I could clean your fuel and tanks and return the good fuel. You’d lose maybe 10 gallons,” Trent says. “Now, if I test it and it [contains] ethanol, I’m going to dispose of [all] this material.” (Leave tank cleaning to trained professionals with proper equipment, though. Shop-Vacs and water pumps can ignite gasoline fumes.)
Again, phase separation, corroded tanks and clogged filters are exceptions, not the norm. “I’m not big on taking things apart just to take them apart,” says Rick Panasuk of Ocean Spray marine Service in Bellmore, New York. “We’ve had ethanol here for five years now. It isn’t necessary to spend hundreds of dollars needlessly.”
Monitor rubber hoses and check for water in tanks. Beyond that, Panasuk says, any change from “normal” warrants service. Low power might indicate clogged fuel filters or injectors. Fuel-injected engines that stutter at high speed should visit a mechanic, as should carbureted engines that don’t accelerate smoothly from idle. Ethanol causes hard starts when cold, but once warm, engines shouldn’t stall. “Spin off the water separator after the first run of the season and check for water,” Panasuk says. He also warns that ethanol problems are worse on boats that sit. “The guy using his boat lightly really needs to do more.”
In short, ethanol requires boaters to think about fuel instead of putting it in the tank and going. Considering the consequences of a fuel leak or water-related problems — with or without ethanol — added attention to fuel systems is a good thing. When ethanol comes to town, it can cause its share of problems, but given the facts across the board, for most boaters it doesn’t necessarily suck as bad as you might have thought after all.