Bass Club Digest

Pouring a little white lightning in the tank might have been a great way for the Dukes of Hazard to outrun Boss Hawg, but it’s not such a great idea for improving performance in your bass boat. No matter, anglers around the nation are dealing with the addition of ethanol—moonshine, but denatured moonshine—to their gasoline these days. Some have reported problems as a result of using the mix, labeled E-10—that is, up to 10 percent ethanol, 90 percent gasoline.

E-10 is aimed at reducing harmful pollutants in the air, cutting dependence on foreign-sourced fossil fuels and putting American farmers to work. All noble goals, but there’s no question its introduction caused some costly issues for boaters when widespread distribution began nationwide about three to five years ago.

In fact, there were some horror stories of the engines in big yachts being destroyed as a result of the alcohol dissolving the sealants of fiberglass fuel tanks, then cycling the resulting gunk through the motors. And there were also plenty of cases where anglers with smaller rigs, including bass boats, had to make costly repairs as an apparent result of introduction of the new fuel.

Why should E-10 cause problems for boats when it doesn’t seem to do so for automobiles?

Primarily two reasons, according to Boat U.S., (www.boatus.com) a boaters’ rights group that has studied the issue extensively.

First, the fuel used in the typical automobile doesn’t stay in the tank long; most of us fill up weekly or even more frequently. Boat fuel, on the other hand, often remains in the tank for weeks, and in the case of over-wintering, for months. That gives it lots of time to attract water, something it does very well according to engineers at Mercury Marine. With your boat sitting at the dock on your home lake, or even on a trailer under cover, the humidity in the air and the changing temperatures from day to night will cause condensation inside the tank.

So long as there’s a modest amount of water in the gas and the mix gets burned off regularly, no problem. However, if the water accumulates and stays in there a long time, it may undergo what engineers call “phase separation”, with the water binding with the alcohol and separating from the gasoline. This mix is heavier than the gas, so it sinks to the bottom where your fuel-pickup is located. If a two-stroke engine without oil injection gets a lung-full of this stuff, it’s likely to make expensive noises because there will be no oil in the mix. It’s less damaging to four strokes, but will cause very rough running and hard starting—or not starting, period.

However, in most cases, the worst does not happen; E10 is conditionally OK for outboards; nearly all modern outboard makers, including Evinrude, Honda, Mercury, Suzuki and Yamaha say that their outboards can burn E10 gasoline without harm. (Note that Nissan/Tohatsu is not included in this list—they caution against the use of E10 in their owners manuals thusly: “Damages resulting from use of ethanol . . . are not covered under warranty.” They go on to cite corrosion, deterioration of rubber and plastic parts, and wear to bearings, rings, cylinder and pistons as possible results of using ethanol-containing fuel.)

But even for those engines which have the OK for E10, there’s reason for caution. For one, fuel suppliers say that E10 is often mixed into the fuel by secondary distributors, who may or may not have an accurate control of the volume. Some random fuel tests by Suzuki Marine found up to 15 percent alcohol in pump fuel according to company spokesman and test expert Dave Greenwood.

“That much alcohol is likely to cause engine problems, and it can also void your warranty,” cautions Greenwood.

And second, ethanol is a great solvent, very good at dissolving all sorts of gunk that might have formed inside your fuel tank over the years. When you first fill up with a tank of ethanol-mix, a lot of the crud that is inside your tank is likely to go into solution and then through your injectors or jets into the engine, where it can cause sticking rings and other expensive problems as it’s burned.

Martin Peters, spokesman for Yamaha, reports that the company saw an unusual number of valve problems on four-strokes when ethanol was introduced in some areas around the nation.

“We eventually figured out that residue dissolved by ethanol in the fuel tank was building up on the valve edges and stems. This not only caused rough running but in extreme cases it caused the piston to hit the valves, which resulted in major damage,” Peters said.

On older engines—pre 1990’s—the fuel hoses and fittings themselves can be dissolved or compromised. Of course, if you’re still running one of these old motors, chances are good you’ve already had to replace fuel lines and other components due to normal deterioration, but if not, now would be the time to do so.

Fortunately, according to most outboard manufacturers, with a few precautions you can avoid serious gasohol troubles. Here’s what they recommend:

Buy your fuel at high-turnover stations or marinas where it’s less likely that water or contaminants will build up in the supply tank. Note that marinas, in general, don’t turn over their fuel as fast as high-volume landside gas stations. Plus, you’ll get your fuel cheaper if you buy it ashore. (On the other hand, if you don’t support your local marina, it may not be there next year—it’s a double-edged sword.)

Keep your boat’s tank as full as practical; fill to 95 percent capacity if you expect not to run the boat for a month or more—this cuts down on the amount of condensation resulting from humid air entering through the tank vent. (Why isn’t this a problem in automobiles? For one, they have closed-system fuel tanks without vents that allow high-humidity air to enter as boats do.)

Add a fuel stabilizer regularly. Though stabilizers do not solve the potential problems of ethanol, they keep other gunk from settling out of gasoline, thus giving you that much of an edge over untreated fuel. Makers like StarTron, Sta-bil and ValvTect say that treated gasoline is good for up to a year in your boat’s tank, while it may start gumming in as little as six weeks otherwise. The manufacturers say that a small amount of treatment goes a long way, with mixes as low as an ounce per 15 gallons adequate to avoid most issues with fuel aging. Some treatments also help prevent water/ethanol from settling into the bottom of your tank where it will be sucked in by the fuel pickup.

Add a 10-micron filter to your fuel system in addition to the engine-mounted filter that came with your outboard, and change the filter regularly. (A micron is a millionth of a meter—or about 1/50th the diameter of a typical human hair.) Filters are available in 40, 30, 20, 10 and 2 micron capability. The 40’s and 30’s, typical of the small in-line filters that come with your outboard, are not adequate to get rid of the sorts of contaminants that ethanol may set loose in your system, while the 2’s are so small that the filters have to be swapped out almost weekly if you run the motor much—the 10’s are the best compromise. The filter body sells for around $55 through discount houses like West Marine (www.westmarine.com). The good ones like Raycor include a drain at the bottom of a clear bowl. You can see when water or contaminants build up, and drain them out. You still occasionally have to replace the filter element, typically once a year, at a cost of around $30. The intense filtration provided by these filters stop most contaminants that might be flushed out of your tank by ethanol.

Check the engine mount or in-line filter regularly and replace anytime you see water or debris in the bowl. These filters sell for under $10.

Use a fuel test kit to check ethanol levels in gasoline you buy. Some stations sell blends that have higher than the recommended 10 percent; avoid these stations. (The reusable test kits are about $25 and are offered by numerous makers--check www.fueltestkit.com and others.)

Yep, I know what you’re thinking—this is quite a bit of trouble to fix something that was not broken before they started with the E10. In some areas, it’s still possible to buy all the gasoline you want without ethanol. There are two small ethanol-free stations within 10 miles of my home on Smith Lake, Alabama, and they do a brisk business with boaters driving in from all over the county to fill up. Not only does using ethanol-free gas provide them with assurance they won’t face the problems reviewed above, but straight gasoline has more energy per gallon, thus delivering slightly better mileage—reportedly about 2 percent.

In general, though, it appears that ethanol-mix is going to be the fuel of the future, so we might as well get used to dealing with it. Bottom line is that the vast majority of boaters have done a lot more worrying about ethanol than is necessary. If you follow a few simple precautions, you’ll probably have no more problems in the age of E10 than you did prior to the days when you stoked your kicker with white lightning.

SIDEBAR: More Ethanol Ahead?

The ethanol industry is pushing to increase alcohol levels from the currently-allowable 10 percent to 15 percent, something that outboard builders without exception say would be harmful to their products. On Sept. 14 the Mid-Level Ethanol Blend Act of 2009 was introduced in the U.S. Senate. The bill—backed strongly by the National Marine Manufacturers Association--would block the increase, at least until studies can be done to conclusively show the potential impact. If approved the law would require a survey of potential issues within 180 days of passage, and would then allow up to three years for in-depth scientific studies of the effects of alcohol on various types of engines, including particularly marine engines and outboards. If this sounds like a good idea to you, contact your Senator and ask them to support passage of S. 1666.

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