Boat Builders warned of liability for Ethanol damage

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A CLASS action suit in California could be a foretaste of what we may see in Australia. US Boat owners, whose fibreglass fuel tanks were "melted" by ethanol blended gasoline, are seeking compensation from the courts, and we could see that happening here if boat builders don't move quickly.

The USA has had fuel tank standards that can cope with ethanol blends for almost 10 years. But even today boats are being produced in Australia that could be destroyed by one tank of E10.

The industry has been give a wake up call by the recent announcement from the Queensland government of a mandate for five per cent ethanol by 2010.

This follows a two per cent mandate by the NSW Government in late 2007.

Ethanol is a risk for boat owners for two key reasons. It's a powerful solvent, dissolving sediments, melting some hoses and damaging some aluminium and especially fibreglass fuel tanks. On top of that, it doesn't stay mixed with petrol, meaning it has a very short shelf life.

The writing is on the wall, most governments considering ethanol as a way to support farmers and reduce fuel imports. E10 (10 per cent ethanol 90 per cent petrol) is going to be much more mainstream.

David Heyes, Chairman of OEDA the outboard industry peak body, recently said that his members were alarmed. He stated that while almost all modern outboards will at least tolerate E10, the outboard industry was very concerned with the potential damage to fuel systems and especially for the safety of boat owners.

Most outboard engines can cope with 10 per cent ethanol. It's in the fuel system and storage issues that will do damage to boats.

Ken Evans, director - outboards for Mercury, has been studying the effects of ethanol and concluded ""Ethanol E10 fuel absorbs water readily and easily, therefore it is suggested that it not be used for marine applications".

"All of the government research so far has been far too narrow and they have missed the point that the problem is not with outboards but with fuel systems."

According to Paul Dawson, BRP-Evinrude's guru on all things marine, ethanol is going to liberate dirt and deposits that you never know you had - from the very first tank.

A 2004 federal study conducted by the Orbital Company in WA tested nine identical 15hp Mercury two-strokes and found they were mostly compatible with E10. The conclusion ignored fuel tanks and shelf life issues and concluded that there were no problems with ethanol in marine applications.

Ethanol blended fuels have been used in the US for some years and the risks to boats are well documented.

Boats with fibreglass tanks are most at risk from the solvent properties of ethanol. They are soon attacked with ethanol, dissolving the resins, eventually weakening the structure and causing leaks. Leaks that can lead to fires.

Boat USA conducted tests on two boats that had suffered suspected ethanol damage. The 1967 and 1970 Bertram both showed signs of engine and fuel system damage.

They found black material on an intake valve which indicated esters, keytones and polyester. In other words the fibreglass fuel tanks and perhaps fuel lines were dissolving and these chemicals were passing straight through the filters before being deposited inside the outboards.

The fuel in the tanks showed styrene, a component of polyester resin. The tanks were also tested and showed to have "aggressive degradation" and had lost 40 per cent of their strength.

Aluminium tanks risk increased corrosion. In the presence of very small amounts of chloride (from salt water) or copper (from brass fittings) there will be a reaction that dramatically increases corrosion and in the end will mean leaks and the obvious safety risks. It's going to be a good year for plastic and stainless steel tank manufacturers.


Ethanol is "hygroscopic" and absorbs moisture. Up to 0.5 per cent absorption is not a problem but beyond that the saturated ethanol sinks to the bottom of the tank in a process called Phase Separation.

There is always going to be condensation in fuel tanks, especially boat tanks.

Shaking and stirring won't put the two fuels back together. Most expert reports say that there are no additives that can do the trick either. We have found one preventive additive company that claims its product delays phase separation. The jury is out and the product is currently only available in the USA.

When fuel separates low octane petrol is left at the top. Ethanol is 100 octane so when its separates the remaining fuel drops about three points from say 91 ron to 88 ron. That meets "pinging" and engine damage.

At the bottom of the tank is a 100 per cent dose of ethanol. When this builds up enough to reach the fuel pickup we get a dose of 100 per cent solvent ethanol running though lines, filters, fittings and engines designed to cope with E10, and no more. That has to mean damage and the risk of fuel leaks.

Once phase separation occurs the only solution is to completely empty the tank, and clean out any ethanol and water in the bottom.

Keeping fuel tanks full will reduce the amount of air and cut back in condensation. But full tanks increase the risk of sour fuel when boats aren't used every week. (The writers suggestion of a law making weekly boating compulsory didn't get a response from the Minister - sadly)


Consumers don't know that E10 isn't the bargain it's made out to be.

Ethanol has a heating value of 47 MJ/kg, which is approximately 30 per cent less than petrol. That means that a 10 per cent mix (E10) will lose about three per cent in fuel economy. Well at least in theory - each engine will differ.

So if unleaded fuel is $1.70 per litre, E10 has to be under $1.65 just for the buyer to break even. Currently the price difference is closer to three cents - hardly a bargain.


Gas stations already have the occasional customer who puts diesel in their petrol car, so there is going to have to be a huge effort by industry if we are going to stop E10 getting put into boats, by accident or on purpose.

The 3 cpl price incentive is going to be too much for some boat owners to resist.

What is needed urgently is for boat builders to voluntarily change over to approved plastic or stainless steel tanks. Marine associations are having urgent discussions about changing boat building standards - but it's all catch up.

I'll stick my neck out further and suggest and ask that AMIF or OEDA or both produce a "No Ethanol" sticker as an urgent first move, and make them available to boat builders and boat yards. That on top of an extensive public education campaign.

That won't guarantee they won't face legal action - but it's got to help.

Special thanks to Ken Evans of Mercury and Paul Dawson of BRP Evinrude for their advice.


We contacted BP, Shell and Caltex during research and they all advised that boat owners should not use ethanol mix fuels in boats.

They each told us that their warning was mostly because ethanol has a dramatically shorter life expectancy, especially in a marine environment.

In a special statement to the Marine Industry 2 July; 2008, Minister for Industry Desley Boyle said that the Queensland Government is committed to a five per cent ethanol mandate by 2010.

"In light of increased world oil prices and global environmental pressures ethanol is going to play an important part in future fuel production and consumption in Queensland," Ms Boyle said.

"The main reason the Queensland Government has not mandated ethanol sooner is the importance of education to car and other vehicle owners and to give the industry time to prepare for production and distribution.

"This is highlighted by some issues raised within the boating industry regarding the suitability of ethanol blended fuels for some engines and fuel tanks.

"Most motor vehicle manufacturers provide advice about suitability for use with ethanol blended fuels and I would encourage other engine manufacturers, if they haven't already done so, to make this information available as well.

"Under the Queensland mandate consumers will still be able to purchase regular unleaded fuels.

"Obviously once the mandate is in place we will run further public awareness campaigns emphasising the need to ensure people's vehicles are suitable for use with ethanol blended fuels before they make the choice to switch," Minister Boyle said.


The bottom line seems to be that modern outboards are fine with fresh ethanol up to E10, but they warn about fuel system risks.

Evinrude: Evinrude motors can tolerate up to 10 per cent alcohol in fuels, (which is the maximum currently sold in Australia)

Honda: Honda engines are designed for good performance and efficient operation using gasoline containing from 0 to 10 per cent ethanol.

Mercury: Mercury engines will withstand up to 10 percent ethanol in gasoline.

Suzuki: Recommends the use of pure gasoline without alcohol, but can use up to 10 per cent alcohol if necessary.

Tohatsu: Recommends use of fuel up to only 10 per cent ethanol. Voids the warranty for all alcohol-fuel related malfunctions.

Yamaha: All 2008 and later models are suitable for use with Ethanol E10 blended fuel. Models prior to 2008 are not suitable for ethanol blended fuels.


Basically ethanol is a form of alcohol and made in much the same way, by fermenting crops. In the USA it's made from corn, in Europe from sugar beet and wheat stalks. In Australia it seems to be sourced from sugar cane.

It's used in petrol for a number of reasons. First it stretches out the available petrol which is a good thing with rising fuel costs and the fear that oil will run out.

It also oxygenates the fuel, enhancing the octane but with less environmental damage than MTBE currently used. Pure ethanol is about 100 octane, so added to petrol it's an octane enhancer.


In June a California law firm filed a class action lawsuit in U.S. District Court in Los Angeles, alleging oil companies failed to inform boat owners that ethanol causes damage to fibreglass fuel tanks.

The suit seeks to represent a class comprising all owners of boats with fibreglass fuel tanks who filled their tanks with ethanol-blended gasoline from a California retailer. The suit also seeks to represent all persons in California who own boats with fibreglass fuel tanks that had to be replaced because of damage caused by ethanol-blended gasoline bought from a California retailer.

The lawsuit, filed by Kabateck Brown Kellner, LLP, names major oil companies, including Chevron and Exxon Mobil Corp., as defendants.

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