Randy(308)sent this article from the Corpus Christi Caller Times. This is good information for boat owners.

COASTAL BEND — Routine corrosion problems are never ending for Coastal Bend boat owners.
And now that ethanol is being distributed more widely in Texas — and a mixture of up to 10 percent ethanol is sold at all Corpus Christi Valero and Stripes stores — local boat mechanics tell me they expect ethanol-related problems to increase, particularly with older outboards and boat components.
The lower the ethanol content the better, said service specialists Marty Benge (361-937-7800) at Gulf Coast Marine and Kerry Henry (361-994-0317) at Ronnie’s Marine. The trouble is, ethanol mixtures vary in potency from place to place and, in some cases, from season to season in certain regions. But 10 percent is the maximum for now for us.
If a push for 15 percent ethanol goes through, then we’ll have real problems, Henry said.
All new model outboards can run fine on what’s called E10 (up to 10 percent ethanol). However, performance and efficiency may suffer. But with routine maintenance and several precautions, problems can be reduced, Benge and Henry said.
I could not confirm this, but a report circulating around the boating community claims that a local man tested ethanol content at several local pumps. He found at least one retailer that consistently dispensed fuel that contained considerably more than 10 percent ethanol.
To conduct your own test, talk to Kevin at Coastal Bend Lawn & Garden in Portland. Call (361) 777-0277. As for a Gasohol Test Kit.
In other parts of the country ethanol essentially melted or dissolved the insides of fuel tanks made of fiberglass. Newer fiberglass tanks are not a problem. Fiberglass fuel tanks are not popular here, but at one time were being installed mostly on high end larger boats made by Hatteras, Bertram and Chris Craft in the 1960s and 70s and later were installed on some Boston Whalers.
Because alcohol is a solvent, this property also can result in the breakdown of other boat components such as rubber fuel lines. This breakdown results in a gummy sludge that can find its way into the engine and clog fuel filters and valves, leading to engine failure.
Newer boats are equipped with ethanol resistant parts.
Ethanol’s solvent quality also can loosen residual varnish, rust and grim throughout the system, again, clogging fuel filters, jets, carburetors and injectors and causing engine failure.
If you have old fuel in your tank, it’s best not to mix it with E10. And change your fuel filter after at least every 50 to 100 hours of use.
Ethanol not only is corrosive but it absorbs water, which can cause fuel to separate. The water-alcohol mixture then sinks to the bottom of tanks or engines and wreaks havoc.
If you don’t have a fuel-water separation filter, get one. Henry and Benge recommend one rated at 10 microns. They also recommend a fuel stabilizer, which should be an additive recommended specifically for your outboard. Local mechanics like Johnson-Evinrude 2+4 stabilizer, but, again, consult your owners manual. Don’t be taken by fuel additives that claim they can offset ethanol-related problems. Go to a reputable marine dealer.
Below are symptoms, recommendations and more information on ethanol as it relates to boats and motors.
RECOMMENDATIONS
- Use components compatible with ethanol and replace those that are not (check with your boat mechanic)
- Install a large capacity fuel water separation filter (10 micron) if you don’t already have one.
- Carry extra FUEL filters onboard.
- Keep your fuel tank full.
- Smaller horsepower engines should consider using small capacity portable fuel tanks.
- Try to use the same source for fuel every fill-up.
- When using a fuel stabilizer, always add fresh stabilizer to fresh fuel.
- Use your boat frequently to avoid stale fuel.
- Never combine old fuel that has darkened with fresh E10 fuel. The resulting gunk will clog filters and result in costly damages.
- If you have old fuel in your tank, bring it to a marine dealer for disposal. There will be a fee.
- Buy from high-volume fuel retailers.
- Use only manufacturer recommended fuel additives.
- Do not knowingly use fuel with more than 10 percent ethanol.
- Check hoses often for cracking or other signs of softening, hardening or leaks.
- Check your fuel tank for water and separation.
- Replace your fuel filter often.
- Some manufacturers recommend adding a carbon guard to each fill-up to avoid rust, carbon build up and piston ring sticking.
- Keep your engine well-tuned and lubricated.
POSSIBLE SYMPTOMS OF ETHANOL USE
- Engine stalling, poor acceleration, sputtering or poor idling.
- deterioration of parts, particularly rubber, gaskets, aluminum and fiberglass.
- Ethanol produces 28 percent less energy than gasoline alone, so expect a reduction in power and fuel economy.
- Water in fuel tank and/or in the engine.
- When ethanol combines with water and sinks, the remaining fuel is lower in octane than originally. This leaner fuel can lower performance in four-stroke engines and can damage two-stroke engines.
- The more frequent problems caused by ethanol involve damage to components within the boat not the motor, such as the fuel tank, fuel hoses and the primer bulb.
David Sikes’ Outdoors column runs Thursday and Sunday. Contact David at (361) 886-3616 or sikesd@caller.com.