Ethanol and Boat Motors Don’t Mix

Boat Motor

Ethanol and Boat Motors Don’t Mix

Venerable Washington Post outdoors writer Angus Phillips had a few words to say about ethanol and boat motors in his 18 Nov column, … mostly words born of frustration.

Here’s a few of the lead in’s to his advice column about how to keep your boat motor from being a victim of ethanol

The villian is e-10, the ethanol gasoline mix that is now standard issue at most fuel pumps …

E-10 means 10 percent ethanol, which is basically corn alcohol … it poses a problem in boats …

If you prowl Internet boating and fishing sites or recent marine industry publications you’ll find millions of words on the perils of e-10 ...

Here’s the article, …

An Inconvenient Truth: Green Motors Are Anything but Smooth Sailing

By Angus Phillips
Sunday, November 18, 2007; D06

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.

Add the manufacturer’s recommended amount of fuel stabilizer to every tank when you fill up, unless you’re going to burn up the tank within a week or so. The two most popular stabilizers are Star Tron and Sta-Bil, both of which Noyes said help keep ethanol from separating, and as a result keep water that gets absorbed in the fuel from accumulating in troublesome concentrations at the bottom of the tank. (And yes, fuel stabilizers are expensive).

“But you must put the stabilizer in when you fuel up,” he said. “It doesn’t do any good to do it afterwards.”

Noyes said engines most severely affected by E10 appear to be two-stroke, fuel-injected outboards, followed by two-stroke, carbureted outboards. Inboard-outboard engines rank third on his hit list, followed by four-stroke outboards and finally by inboards.

Some older inboard-powered boats basically can be put to death by E10. Cabin cruisers and the like built before 1986 may have internal fiberglass fuel tanks that are molded into the hull. E10 eats at the fiberglass and turns it to jelly, and the only way to remove the tanks to replace them with stainless steel, aluminum or modern plastic is to chainsaw through the hull. “That’s why you see a lot of old cabin cruisers rotting away on shore,” Noyes said.

It’s been a hard summer on my small-engine fleet, and E10 is the prime suspect. In September, the old 70-horsepower Evinrude gave up the ghost during a fishing trip to the Bay Bridge. It went with a flourish at full speed, little parts clattering in the combustion chambers before it locked up altogether. Oh well, it was34 years old. . . .

Then the Johnson 25 on the crab boat kept breaking down at speed and refusing to start. After rebuilding the carburetor once, the normal answer to a fuel delivery breakdown, Noyes showed me a little trick — just remove the fuel drain at the bottom of the carburetor and pump fresh fuel through, onto a paper towel. “A lot of the time that’ll push the gunk out and solve the problem,” he said. And it did!

Now it’s November and time to put everything to bed for the winter. What to do to ensure a stress-free first outing next spring? Stabilize the fuel in the recommended amount and leave the tank about halfway full of fresh gas, Noyes said. Fog the motor with fogging oil the usual way, and put a new, 10-micron cartridge in the fuel separator before setting out in the spring.

That’s the plan. But who knows what really works? I read on the Web site last week that the worst thing you can do is fill the tanks halfway for the winter.

We’re all working in the dark here, plugging along blind in a world where everything keeps changing.

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