unresolved technical concerns (FORD on biodiesel) (Score 4, Informative)

There are still some unresolved technical concerns with the use of biodiesel at concentration greater than 5%. Some of the concerns are:
        Requires special care at low temperatures to avoid excessive rise in viscosity and loss of fluidity
        Storage is a problem due to higher then normal risk of microbial contamination due to water absorption as well as a higher rate of oxidation stability which creates insoluble gums and sediment deposits
        Being hygroscopic, the fuel tends to have increased water content, which increases the risk of corrosion
        Biodiesel tends to cause higher engine deposit formations
        The methyl esters in biodiesel fuel may attack the seals and composite materials used in vehicle fuel systems
        It may attack certain metals such as zinc, copper based alloys, cast iron, tin, lead, cobalt, and manganese
        It is an effective solvent, and can act as a paint stripper, whilst it will tend to loosen deposits in the bottom of fuel tanks of vehicles previously run on mineral diesel

https://www.fleet.ford.com/showroom/environmental_ vehicles/BiodieselTechnology.asp