Having announced its concerns over the reported October implementation of B10 biodiesel, BMW Group Malaysia has brought our attention to a 2012 joint-statement by five diesel injector manufacturers – Delphi, Denso, Bosch, Continental and Stanadyne – detailing the possible effects of biofuels, or fatty-acid methyl esters (FAME), on diesel engines.

Fuel sources like rapeseed methyl ester, soybean methyl ester and palm oil methyl ester are collectively known as FAME. The statement says, “It must be recognised that the physical and chemical characteristics of bio components are significantly different to conventional fuels and that care must be taken in their specification and use,” adding that “many vehicles, engines and equipment are not designed to run on them.”

The statement reveals that the European diesel fuel standard EN 590:2009 covers diesel blends with up to 7% FAME (B7 biodiesel), but adds that the FAME standard EN 14214:2009 is being extensively revised to facilitate blending of up to 10% FAME (B10 biodiesel).

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While the companies do not specifically single out any ‘bad’ blends, and understand the need for continually revising standards, they raise issues regarding reduced fuel stability (leading to “plugged filters, sediments and sticking moving parts”), impurities in the fuel and compatibility issues with older vehicles (most likely affecting filters, hoses and seals), with FAME.

The statement further cites EN 590:2009 section 5.4.3, which says “Diesel fuel shall be free from any adulterant or contaminant that may render the fuel unacceptable for use in diesel engine vehicles”. Perhaps the more technically- and scientifically-aligned amongst you can shed some more light on this – the full statement is below.