Ethanol, Fibreglass, and now Biodiesel warnings

...but what is the fuel tank made from...?
.. .
This week a Los Angeles firm has filed a class-action law suit against US oil companies on behalf of Californian boaters with fibreglass fuel tanks. Some fibreglass fuel tanks can be dissolved by ethanol enhanced fuel and the flow of the dissolved mixture then damages the engine, costing boat owners thousands.

The presence of ethanol in gasoline or methanol in diesel (biodiesel) is a hot and lasting issue for boat owners, be they sailing boats or powerboats. Corn based ethanol has been in the US since 2005 in an effort to lower vehicle emissions, and unsuspecting boat owners used the fuel.

Two industry experts, C Douglas Nielson and Laurence Burgin, discuss the issues:

Award-winning freelance writer and a conservation educator C Douglas Nielson writes:

'Not long after the gasoline suppliers in the Long Island area of New York switched to ethanol-blended gasoline, the Boat Owners Association of The United States (BoatUS) started receiving reports of ethanol-related problems from boat owners. According to an article in Seaworthy, a BoatUS newsletter dealing with marine insurance issues, there were 'several engines in the Long Island Sound area that seemed to have been badly damaged when fiberglass tanks that had been filled with ethanol-enhanced gasoline started to fail. Some of the tanks had begun leaking.'

'Similar reports came in from California and the Great Lakes area, so BoatUS conducted tests to confirm whether the problems associated with fiberglass tanks were linked to ethanol-blended fuel. The results showed that tanks exposed to the gasoline mixture lost as much as 40 percent of their structural strength.

'While attending a boat accident investigation course a few years ago, I learned that fumes from a single cup of gasoline spilled or leaked into the bilge of a boat could result in an explosion equal to that of several dynamite sticks. It then would be logical to believe that dissolving fuel tanks could lead to an explosive situation.

'Most of the reports received by BoatUS involve fiberglass tanks made before the mid-1980s by manufacturers such as Hatteras, Bertram and Chris Craft, but any boat with a fiberglass fuel tank that was not designed to be used with ethanol-blended fuels probably should be considered suspect. It's also a good idea to check fuel hoses for leaks or deterioration.

'In addition to weakened gasoline tanks, boat owners also have reported significant engine damage as components in the fiberglass dissolve and pass through their boat's fuel system. The reports described symptoms that include a black sludge that builds up on engine components such as intake manifolds and valves. This sludge is the result of a chemical breakdown in the fiberglass and causes engine parts to stick, and it eventually destroys the motor.

'Like most boaters, Lawrence Taylor, a 50-year-old California attorney, was unaware that ethanol-blended gasoline could weaken the integrity of his vessel's fiberglass gasoline tank. It wasn't until he had to cough up $35,000 for boat repairs that Taylor became aware. So he decided to do something about the situation and filed suit in federal court. Among the 10 gasoline producers and distributors listed as defendants in his suit are Chevron and Exxon Mobile.

'Taylor's argument, as reported in the Los Angeles Times, is that the defendants failed to warn boaters that using ethanol-blended gasoline could damage their vessels.

'An article in ABA Journal, an online publication of the American Bar Association, quoted Shell Oil Co. president John Hofmeister as saying his company was not at fault because 'there were years of advance notification that this change was coming.' He contends that 'any boat owner or any boat seller or any boat maintenance shop that didn't know about this impending change and the potential consequences simply wasn't listening or reading.'

'So what can boat owners do now? If the fuel tank on your boat is made of fiberglass, my suggestion is to have your mechanic inspect the tank to make sure that its integrity has not been compromised. If necessary, replace it with something that will stand up to ethanol. Your mechanic can help you with that as well. It might cost you a few bucks, but gasoline isn't anything to fool with. I've seen the aftermath of vessel explosions.

'For more information on the subject as relates to gasoline, read a synopsis of the BoatUS test results online at And have a dictionary handy.'


Australian marine industry expert Laurence Burgin of Marine Stainless expect more challenges ahead for the marine industry as increasing numbers of boaters may want to use biodiesel in their tanks, or ethanol enhanced fuel in their outboard motors.

'The Marine Industry certainly should take this issue seriously - it can affect seaworthiness' he said. 'Before using biodiesel, boat owners should check - or have checked - every area where biodiesel will flow - the tank, the fuel tank filler lines, breather lines, the fuel supply and return lines, tank gauge sender unit gasket, the fuel lift pump, and fuel lines should be made of nitrile rubber.

'The methanol which is used in biodiesel production tends to clean the deposits in the system. These deposits end up in the primary fuel filter(all diesels should have a primary filter for problems like this) and secondary fuel filter on the engine. This would cause them to block and the engine to fail from lack of fuel. A filter change (naturally you will have spares on board) will solve the problem. This problem can recur if there is intermittent use of biodiesel.

'In outboard motors, the fuel pump, the carburettor, fuel injection system - all these could be affected.

'If you are not sure, ask the manufacturer of the boat, or in the case of outboard motors, the manufacturer of the outboard. If this is not possible, go to a reputable member of a Marine Industry Mechanical Repair Association for advice, or refer to Fibreglass supply companies

'Older fibreglass tanks, which were made from polyester resin are more at risk than newer tanks which tended to be made with vinylester. If you are unsure about your tank, seek advice from a professional.'

'Many companies are using plastic rotary molded tanks these days which are generally made from polyethylene, some made from polypropylene man not be suitable. Fabricated custom polyethylene tanks are an economical replacement alternative

'Changing engines from old gas eaters to new efficient diesels should be considered in the big picture.'

Laurence finishes his advice with an extra comment: 'Also one could consider, in the big picture, the notion of using food for fuel!'

To contact Laurence Burgin for further information or advice, go to his webpage