While this is good for the domestic farmer and our environment, Ethanol can cause serious problems to your engine and fuel system. Generally vehicles built after 1996 have been designed with Biofuels in mind, but earlier cars and engines with carburettors are going to need help. What types of problems have been encountered?
1) Water accumulation in the fuel tank
Ethanol absorbs water from the air. The water condenses in the fuel tank and will pull the ethanol out of suspension with the petrol. This is bad news because it strips the octane out of the petrol, leaving you with a layer of octane-poor fuel on top and a water-ethanol layer mixture on the bottom. If this gets sucked into the combustion chamber, you will have poor starting and very rough running with potentially engine damage.
2) Deposit is like to build up
Ethanol when mixed with water readily forms Gums in the fuel system much quicker than fuel without Ethanol. These Gums coat fuel system components including filters, carburettors, injectors, throttle plates and will then form varnish and carbon deposits in the intake, on valves, and in the combustion chamber.
3) Lower fuel mileage, decreased performance and acceleration
Ethanol contains less chemical energy than petrol does, and this means less mileage for the driver. 3-5% drops in mileage are expected.
4) Corrosion of internal engine components
Water contamination may cause fuel system corrosion and severe deterioration.
5) Contaminants in fuel system
Water, degraded rubber, plastic, fibreglass and rust may get drawn in.
6) It could encourage microbial growth in fuel
Ethanol being organic and hygroscopic may allow the growth of fungus.
7) Short shelf life
As short as 90 days.
8) Corrodes plastic and rubber
Ethanol is a strong, aggressive solvent and will cause problems with rubber hoses, o-rings, seals, and gaskets. These problems are worse during extended storage when significant deterioration could take place. Hoses may delaminate, o-rings soften and break down, and fuel system components made from certain types of plastics could either soften or become hard and brittle, eventually failing. Fuel system components made from brass, copper, and aluminium may oxidize. The dissolved plastics and resins now in the fuel could end up in blocked fuel filters or gummy deposits.
9) Melts Fibreglass
Bikes and boats with fibreglass fuel tanks can have structural failure as the Ethanol will break down and pick-up some of the materials the tanks are made from. Again this material, dissolved from the tank, can be carried through the fuel system and can cause damage to carburettors, fuel injectors and can actually get into the combustion chambers.
