Ethanol mix can spell trouble
THE use of ethanol in petrol can cause problems on boats.
Ethanol is a form of alcohol made from fermenting crops such as sugar cane and corn.
A blended ethanol-petrol fuel has a shorter shelf life than regular petrol; this and ethanol’s strong solvent properties are what cause trouble.
Automotive technology seems to cope with the fuel mixtures sold at most petrol stations but ethanol can damage boat
engines, cause leaks and even melt some kinds of boat fuel tanks.
With governments pushing for an increase in ethanol percentages in petrol, this is an issue that every boater needs to investigate.
Various outboard manufacturers agree that no more than 10 per cent ethanol should be used.
There is no fuel blend sold in Australia with more than 10 per cent ethanol so problems with the engines are limited but fuel systems and fuel storage are not coping as well.
Ethanol is a strong solvent and can release dirt and residue already in boat fuel lines.
If you use ethanolblended petrol, get into the habit of changing your filters regularly to avoid blockages.
The strong solvent properties of ethanol also pose a danger to fibreglass fuel tanks.
If your boat has such a tank, it’s best that you avoid using petrol containing ethanol, because it can dissolve the resins, weakening the tank which can lead to fuel leaks.
The chemicals released from the fibreglass can then also make their way into your fuel system over time.
Ethanol’s tendency to absorb moisture can raise corrosion issues in metal fuel tanks.
But even more dangerous is when this moisture absorption leads to the ethanol and petrol separating, creating portions of 100 per cent ethanol in your tank.
Engines are not made to cope with this, nor are some parts of fuel systems.
It is recommended that you avoid using ethanol fuel blends in boats.
Use premium petrol blends containing no ethanol. If you are ever restricted and have no choice but to use an ethanol blend, drain your boat’s fuel tank when you get home and use that fuel in your car.