An Inconvenient Truth: Green Motors Are Anything but Smooth Sailing

With E10, an ethanol-based fuel, clogging motors that sit for long periods of time, a paddle is the only foolproof way of powering a boat. (By Angus Phillips For The Washington Post)

After a lifetime of fussing around with balky outboard motors, I'm not going to panic at every little setback. Outboards are cranky by nature; they live and work in a hostile marine environment. If you're not prepared for a few unpleasant surprises, you'd better take up rowing or paddling.

But it's getting ridiculous. "A friend of mine who works on small motors has 25 or so just like yours lined up in his shop," said veteran outboard mechanic Scott Noyes, service manager at Shamrock Marine Service in Pasadena. "They're all doing the same thing."

The symptoms should be familiar to anyone experienced with outboards -- hard to start, then popping, sputtering, stalling and breaking down at speed. It could be electrical, as connections and relays get funky over time. But usually when outboards start acting up, it's fuel related.

And never has fuel been a bigger problem. The villain is E10, the ethanol-gasoline mix that is now standard issue at most fuel pumps as the government seeks to decrease air pollution and reduce America's reliance on imported petroleum.

E10 means 10 percent ethanol, which is basically corn alcohol. The ubiquitous mix seems to work fine in cars, which burn through a tank in a hurry. But it poses problems in boats, which sit a lot.

Why? As E10 sits, the ethanol and gasoline start to separate. Ethanol goes to the bottom of the tank. If there's water there, or if water vapor gets in through the vent, the ethanol absorbs it. Before long, you've got a clump of watery ethanol at the bottom of the tank, where the fuel pickup is. When you crank up the motor, the crud is sucked into the carburetor or injectors and plugs things up. The next thing you hear is pop, pop, splutter, sigh . . .

That's not all. Ethanol is a solvent, so when it gets into older fuel systems it can clean out the gunk and varnish that's accumulated over the years and send it upstream to clog tiny fuel delivery apertures as well. It also breaks down rubber gaskets and can turn old fiberglass tanks to mush.

If you prowl Internet boating and fishing sites or recent marine industry publications, you'll find millions of words on the perils of E10, and get more advice than you possibly could digest. I'm by nature a disbeliever in these sorts of magazine crises, which frequently turn out to be concocted by some marketing whiz to sell new, expensive products. I prefer to wait and see whether the crisis is real.

This one's for real. So what to do?

According to Noyes, who deals with E10 problems every day, the most important preventive steps for outboard owners to take are:

¿ Install a water/fuel separating filter between the fuel tank and the engine if one isn't already in place, and spend the extra dollar or two to get a 10-micron cartridge for the filter, rather than the traditional 30-micron cartridge. The finer cartridge does a better job of removing water and impurities, he said.